# Patent

## Title
Treating inflammatory diseases with antibodies that inhibit fractalkine-CXCR1 interaction

## Abstract

A therapeutic agent for an inflammatory disease comprising an antibody or a CX3CR1 antagonist that inhibits an interaction of fractalkine and CX3CR1 is provided.

## Background
TECHNICAL FIELD
The present invention relates to a therapeutic agent for an inflammatory disease.
BACKGROUND ART
Chemokines are major cell migration factors in the living bodies and regulate lymphocyte infiltration into tissues via increase of cell motility and activation of cell adhesion molecules. Chemokines are classified into four subfamilies of CC, CXC, C and CXXXC on the basis of the sequence types of the first two cysteine residues. The members of the CC, CXC and C chemokine subfamilies are secretory proteins consisting of about 70 amino acids, and although they do not have activity as adhesion molecules themselves, they can induce cell adhesion. A secreted chemokine binds to a seven-transmembrane receptor on the surface of a target cell and activates integrin via the trimer G protein to induce cell adhesion or migration.
Recently, a novel simple lymphocyte infiltration mechanism was identified in addition to the known cell migration mechanism. This mechanism is mediated by fractalkine expressed on activated endothelial cells and a seven-transmembrane receptor, CX3CR1, expressed in monocytes, NK cells and a part of T cells in the blood flow. Fractalkine is the only member of the CXXXC chemokine subfamily and has distinct characteristics in the structure and functions thereof that are not found in other chemokines. Fractalkine is expressed on a cell surface as a membrane-bound protein having a chemokine domain, mucin domain, transmembrane domain and intracytoplasmic domain. The membrane-bound fractalkine by itself can mediate strong adhesion by binding to CX3CR1 even in the presence of a physiological blood flow rate without mediation of selectin or integrin. That is, by a one-stage reaction, the fractalkine-CX3CR1 cell infiltration system mediates a function similar to that of the multistage cell infiltration mechanism via selectin or integrin. Further, secretory fractalkine secreted from membrane-bound fractalkine by shedding binds to CX3CR1 and induces integrin activation and cell migration like the known chemokines.
Further, expression of fractalkine is induced when vascular endothelial cells are treated with inflammatory cytokines such as TNF and IL-1. On the other hand, CX3CR1 is expressed in monocytes, most of NK cells and a part of T cells, but not in neutrophils. Therefore, the fractalkine-CX3CR1 cell infiltration system appears to be a very efficient mechanism for mobilizing certain types of immunocytes onto endothelial cells of damaged tissues or into the tissues. Since fractalkine is induced on vascular endothelial cells upon inflammation, and CX3CR1 exists in many types of leukocytes as described above, it is strongly suggested that the fractalkine-CX3CR1 cell infiltration system is involved in development and progression of pathological conditions in inflammatory diseases. In fact, many reports have been made on involvement of the fractalkine-CX3CR1 cell infiltration system in inflammatory diseases, and such reports have been made on many diseases such as rheumatoid arthritis (Non-patent document 1), inflammatory bowel diseases of which typical examples are ulcerative colitis and Crohn's disease (Non-patent document 2), psoriasis and atopic dermatitis (Non-patent documents 3 and 4), asthma (Non-patent document 5), arteriosclerosis (Non-patent document 6), acute respiratory distress syndrome (Non-patent document 7), and so forth. Further, effects of preventing progression of pathological conditions and improving the conditions can be expected to be provided by inhibition of the fractalkine-CX3CR1 cell infiltration system in inflammatory diseases on the basis of the analyses using CX3CR1 knockout mice (arteriosclerosis [Non-patent document 8], tissue damage caused by ischemic reperfusion [Non-patent document 9]), analyses of pathological animal models of inflammatory diseases using anti-fractalkine monoclonal antibodies (mouse type II collagen-induced arthritis, experimental autoimmune encephalomeningitis (Patent document 1), concanavalin A-induced hepatopathy (Patent document 1), analyses of pathological animal models using anti-CX3CR1 antiserum (WKY rat crescentic nephritis [Non-patent document 10], cardiac allograft rejection [Non-patent document 11]), or analyses of pathological animal models of inflammatory diseases using a fractalkine-inhibited mutant (MRL/lpr lupus nephritis [April 2004, Japan College of Rheumatology]), and thus construction of a novel treatment system for inflammatory diseases is expected. However, details of the mechanism of these actions for improving pathological conditions exhibited by the inhibition of the fractalkine-CX3CR1 interaction remain unknown under the present circumstances.
As for the classification of leukocytes, lymphocytes, monocytes and granulocytes have each been classified into small groups on the basis of many cell surface markers so far. Recently, they have been further classified into smaller groups according to the distribution of chemokine receptors, and a group that used to be regarded as one single group is being found to be a collection of several subgroups. It has been reported from analyses of mice that CX3CR1 is expressed in monocytes, NK cells and a part of T cells as described above, and it is being elucidated that there are two groups of monocytes among those, a group of those strongly expressing CX3CR1, but not expressing CCR2 (CX3CR1highCCR2−) and a group of those weakly expressing CX3CR1 and strongly expressing CCR2 (CX3CR1lowCCR2+). Analyses of CX3CR1-knockout mice and CCR2-knockout mice have suggested that the CX3CR1lowCCR2+ monocytes are induced on inflammation sites upon inflammation and contribute to tissue damage by producing inflammatory cytokines such as TNFα and inducible nitrogen oxide synthetase (iNOS) as a potent nitrogen oxide (NO) synthetase (Non-patent documents 12 and 13). However, functions and significance of the CX3CR1highCCR2− monocytes upon inflammation have not been mentioned, and it is rather said that they are necessary for constitutive supply of tissue macrophages when there is no inflammation, and it is undesirable to inhibit functions of these cells.
Further, monocytes in human peripheral blood are also precisely classified on the basis of cell surface markers (CD16, CD62L etc.) and expression of CX3CR1. It is reported that one of the groups, CD16+CD62L− monocytes, increase in peripheral blood in inflammatory diseases, and the involvement thereof in progression of pathological conditions is strongly suggested. Since it has been reported the CD16+CD62L− monocytes highly express CX3CR1, it is anticipated that the CD16+CD62L− monocytes have properties substantially similar to those of the aforementioned mouse CX3CR1highCCR2− monocytes (Non-patent document 14). Further, since it has already been reported that the CD16+CD62L− monocytes strongly produce TNFα and iNOS, they are considered to strongly associate with progression of pathological conditions, along with their increase in peripheral blood in inflammatory diseases. However, there has been no specific report about whether production of TNFα and iNOS by these cells is inhibited by inhibition of the functions of CX3CR1.
iNOS, which has the highest NO synthesizing ability, is not constantly expressed unlike endothelial NOS (eNOS) and neural NOS (nNOS), and it is induced by stimulatory factors (for example, inflammatory cytokines and/or lipopolysaccharides etc.), transiently produced in a large amount and involved in biophylactic reactions such as elimination of bacteria, viruses, fungi or parasites. However, since excessive NO production leads to tissue damage, it is considered that excessive iNOS production in lesions may be a major factor for progressing pathological conditions. Examples of diseases in which NO is actually involved in development or progression of pathological conditions include inflammatory diseases (for example, rheumatic inflammation, rheumatoid arthritis, osteoarthritis, Crohn's disease, ulcerative colitis, psoriasis, arteriosclerosis, autoimmune diseases, acute inflammation etc.), allergy diseases (asthma, atopic dermatitis), ischemic diseases (for example, various cardiac disorders and cerebral disorders caused by infarct or ischemia, reperfusion disorder after ischemia etc.), shock (for example, endotoxic shock, hemorrhagic shock, cardiogenic shock etc.), pathological hypotension (for example, hypotension in cancer treatments using cytokines, hypotension caused by sepsis, hemorrhagic shock or cirrhosis etc.), transplant rejection, nervous system disorders (for example, Alzheimer's disease, epilepsy, migraine etc.), tumors, insulin-dependent diabetes, and so forth.
Furthermore, on the basis of analyses of inhibition of the iNOS activity in pathological models or iNOS-knockout mice, there have been reported improvement of pathological conditions in rheumatoid arthritis (Non-patent document 15), osteoarthritis (Non-patent document 16), inflammatory bowel diseases of which typical examples are ulcerative colitis and Crohn's disease (Non-patent documents 17 and 18), concanavalin A-induced hepatopathy (Non-patent document 19), asthma (Non-patent document 20), endotoxin-induced acute lung injury (Non-patent document 21), arteriosclerosis (Non-patent document 22), ischemic diseases (Non-patent documents 23, 24 and 25), transplant rejection (Non-patent document 22), and so forth.
In fact, improvement of pathological conditions by inhibition of the iNOS activity in many pathological model animals or in iNOS-knockout mice has been reported as described above. However, no promising drug that inhibits the iNOS activity has been launched.
Further, while inhibition of excessive NO production by inhibitors of enzymatic activity of iNOS improves hypotension commonly observed in septic shock, tissue destruction such as that in vasoparalysis and organ disorders, a risk of blocking the fundamental physiological functions of NO such as regulation of blood pressure and blood flow has been suggested (Non-patent document 26). In particular, in the analysis of cardiac muscle functions in sepsis using iNOS knockout mouse, differences in the role of iNOS depending on the type of cells producing it have been pointed out. iNOS expressed in cardiac muscle cells is essential to the useful reaction for shortening cardiac muscle cells by adrenergic stimulus in the event of sepsis, whereas iNOS expressed in inflammatory cells infiltrated in the vicinity of cardiac muscle cells is involved in a harmful reaction of damaging cardiac muscle cells (Non-patent document 27).
Therefore, it has been desired to provide a drug based on a novel approach, that is, inhibition of iNOS activity selective to cell species, for example, not general inhibition of the enzymatic reaction of iNOS, but inhibition of the enzymatic reaction of iNOS or inhibition of iNOS production in inflammatory cells.

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    Non-patent document 27: Circulation, 2003 Sep. 2, 108(9): 1107-12


DISCLOSURE OF THE INVENTION
An object of the present invention is to provide a therapeutic agent for inflammatory diseases, specifically, inflammatory bowel diseases (in particular, ulcerative colitis, Crohn's disease), psoriasis, atopic dermatitis, asthma, arteriosclerosis, tissue damage caused by ischemic reperfusion, acute respiratory distress syndrome, and so forth, based on a novel concept.
On the basis of the previous findings, the inventors of the present invention paid attention to the fact that there had been no report on inhibition of iNOS production and improvement of pathological conditions thereby by inhibition of the function of CX3CR1, thus constructed a hypothesis that a therapeutic agent for an inflammatory disease based on a novel concept could be created by elucidation of the function, and conducted various researches.
That is, investigation was performed by using antibodies inhibiting the interaction of fractalkine and CX3CR1 and the function of CX3CR1 in various animal models described in the examples mentioned later, and as a result, it was found for the first time that they inhibited iNOS production and improved pathological conditions. Further, although it had been reported that the antibodies inhibiting the interaction of fractalkine and CX3CR1 and the function of CX3CR1 are effective for ConA-induced hepatitis, it was found for the first time that they inhibited expression of iNOS mRNA in the liver in ConA-induced hepatitis and iNOS production in inflammatory cells. On the basis of these findings, they showed that an antibody inhibiting the interaction of fractalkine and CX3CR1 and the function of CX3CR1 or a compound inhibiting the interaction of fractalkine and CX3CR1 and the function of CX3CR1 (henceforth also referred to as “CX3CR1 antagonist”) was useful for the treatment of inflammatory diseases associated with the fractalkine-CX3CR1 cell infiltration system and caused by excessive NO production by the iNOS activity or inflammatory cells (inflammatory bowel diseases [in particular, ulcerative colitis and Crohn's disease], psoriasis, atopic dermatitis, asthma, arteriosclerosis, tissue damage caused by ischemic reperfusion, acute respiratory distress syndrome etc.), and thus accomplished the present invention.
That is, the present invention provides the followings.
(1) A therapeutic agent for an inflammatory disease comprising an antibody or a CX3CR1 antagonist, wherein said antibody or said CX3CR1 antagonist inhibits an interaction of fractalkine and CX3CR1.
(2) The agent according to (1), wherein the antibody is an anti-fractalkine antibody.
(3) The agent according to (2), wherein the anti-fractalkine antibody is a monoclonal antibody.
(4) The agent according to (3), wherein the anti-fractalkine antibody is a monoclonal antibody 5H8-4 produced by a hybridoma of the accession No. FERM BP-10372 or a monoclonal antibody #126 produced by a hybridoma of the accession No. FERM BP-10371.
(5) The agent according to any one of (1) to (4), wherein the inflammatory disease is an inflammatory bowel disease.
(6) The agent according to (5), wherein the inflammatory disease is ulcerative colitis or Crohn's disease.
(7) The agent according to any one of (1) to (4), wherein the inflammatory disease is psoriasis.
(8) The agent according to any one of (1) to (4), wherein the inflammatory disease is atopic dermatitis.
(9) The agent according to any one of (1) to (4), wherein the inflammatory disease is asthma.
(10) The agent according to any one of (1) to (4), wherein the inflammatory disease is arteriosclerosis.
(11) The agent according to any one of (1) to (4), wherein the inflammatory disease is tissue damage caused by ischemic reperfusion.
(12) The agent according to any one of (1) to (4), wherein the inflammatory disease is acute respiratory distress syndrome.
(13) A hybridoma Ham @mFKN#126.1.1 of the accession No. FERM BP-10371.
(14) A monoclonal antibody #126 produced by the hybridoma according to (13).
Further, there are also provided a method for treating an inflammatory disease, which comprises the step of administering a therapeutically effective amount of an antibody or a CX3CR1 antagonist that inhibits an interaction of fractalkine and CX3CR1 to a patient who needs treatment of an inflammatory disease, and use of an antibody or a CX3CR1 antagonist that inhibits an interaction of fractalkine and CX3CR1 in the production of a therapeutic agent for an inflammatory disease.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving body weight loss in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 2 It shows scores of stool consistency in the large intestine and effect of the anti-mouse fractalkine antibody (5H8-4) for improving hypertrophy of the large intestine in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 3 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving morphological changes in the large intestine in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes (photographs of organ morphology).
FIG. 4 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving large intestine tissue damage in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes (microphotographs).
FIG. 5 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for various factors in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 6 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving DAI in a mouse oxazolone-induced inflammatory bowel disease model.
FIG. 7 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving large intestine hypertrophy and large intestine shortening in a mouse oxazolone-induced inflammatory bowel disease model.
FIG. 8 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving morphological changes in the large intestine in a mouse oxazolone-induced inflammatory bowel disease model (photographs of organ morphology).
FIG. 9 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving large intestine tissue damage in a mouse oxazolone-induced inflammatory bowel disease model (microphotographs).
FIG. 10 It shows effect of the anti-mouse fractalkine antibody (#126) for improving large intestine hypertrophy and large intestine shortening in a mouse oxazolone-induced inflammatory bowel disease model.
FIG. 11 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of various factors in liver tissue in ConA-induced hepatitis.
FIG. 12 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving increases in iNOS and CX3CR1-positive inflammatory cells in the liver parenchyma in ConA-induced hepatitis (microphotographs).
FIG. 13 It shows results of double fluorescence staining of liver tissues in ConA-induced hepatitis (microphotographs).
FIG. 14 It shows proportions of marker-positive cells among CX3CR1-positive cells and iNOS-positive cells in liver tissues in ConA-induced hepatitis.
FIG. 15 It shows results of flow cytometry of CX3CR1-positive cells.
FIG. 16 It shows results of histological staining of liver tissues in ConA-induced hepatitis (microphotographs).
FIG. 17 It shows expressions of chemokines in ConA-induced hepatitis and effect of the anti-fractalkine antibody (5H8-4) on expressions of chemokines.
FIG. 18 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for leukocyte markers in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes. “Normal” denotes a negative control, “cIgG” denotes the control antibody administration group, and “@FKN” denotes the anti-fractalkine antibody administration group (the same shall apply to FIGS. 19 to 25).
FIG. 19 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for chemokines and chemokine receptors in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 20 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for chemokines and chemokine receptors in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 21 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for cytokines in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 22 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for neovascularization molecules and tissue destroying proteases in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 23 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for molecules activating dendritic cells and T cells in a mouse inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive T lymphocytes.
FIG. 24 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for cytokines, chemokines and chemokine receptors 24 hours after intestinal injection of oxazolone in a mouse oxazolone-induced inflammatory bowel disease model.
FIG. 25 It shows effect of the anti-mouse fractalkine antibody (5H8-4) for improving expressions of mRNAs for neutrophil markers, cytokines, chemokines and chemokine receptors three days after intestinal injection of oxazolone in a mouse oxazolone-induced inflammatory bowel disease model.



BEST MODE FOR CARRYING OUT THE INVENTION
<1> Deposition of Microorganisms
The hybridoma Ham @mFKN5H8-4 was deposited at International Patent Organism Depositary, National Institute of Advanced Industrial Science and Technology (Tsukuba Central 6, 1-1, Higashi 1-Chome, Tsukuba-shi, Ibaraki-ken, 305-8566, Japan) on Sep. 29, 2004 (Accession No.: FERM P-20236), and then the deposition was converted to an international deposition under the provisions of the Budapest Treaty (Accession No.: FERM BP-10372).
The hybridoma Ham @mFKN#126.1.1 was deposited at International Patent Organism Depositary, National Institute of Advanced Industrial Science and Technology (Tsukuba Central 6, 1-1, Higashi 1-Chome, Tsukuba-shi, Ibaraki-ken, 305-8566, Japan) on Sep. 29, 2004 (Accession No.: FERM P-20235), and then the deposition was converted to an international deposition under the provisions of the Budapest Treaty (Accession No.: FERM BP-10371).
<2> Antibody Inhibiting Interaction of Fractalkine and CX3CR1
Antibodies inhibiting the interaction of fractalkine and CX3CR1 can be prepared as follows.
A mammal (for example, mouse, hamster or rabbit) can be immunized with CX3CR1 or fractalkine in the form of an immunogen causing immune responses in the mammal or a protein fragment thereof (for example, peptide fragment).
An expression vector incorporated with the gene of CX3CR1 or fractalkine (for example, see GenBank NM—001337 or NM—002996) is expressed in host cells, for example, bacterial, mammal or insect cells, and CX3CR1 or fractalkine can be purified from a culture medium or bacterial cells or other cells according to a standard method. Further, CX3CR1 or fractalkine can be expressed as a fusion protein with, for example, GST or the like, and may be purified by using a glutathione column in the case of a fusion protein with GST.
A peptide of CX3CR1 or fractalkine can also be synthesized on the basis of the amino acid sequence of CX3CR1 or fractalkine by a known method (for example, F-moc or T-boc chemical synthesis), and immunogenicity of the synthesized peptide can be enhanced by binding it to a suitable carrier, for example, KLH.
After immunization with the purified CX3CR1 or fractalkine or a peptide fragment thereof and an adjuvant, an antiserum can be obtained, and polyclonal antibodies can be isolated from the antiserum if desired. Further, in order to produce monoclonal antibodies, antibody producing cells (lymphocytes) are collected from an immunized animal and fused with myeloma cells by a standard cell fusion method to immortalize the cells and thereby obtain hybridoma cells. This technique is an established method in this technical field, and can be implemented according to a suitable manual (Harlow et al., Antibodies: A Laboratory Manual, 1998, Cold Spring Harbor Laboratory). Further, monoclonal antibodies may be prepared by other methods such as the human B cell hybridoma method for producing human monoclonal antibodies (Kozbar et al., Immunol. Today, 4: 72, 1983), EBV-hybridoma method (Cole et al., Monoclonal Antibody in Cancer Therapy, 1985, Allen R. Bliss, Inc., 77-96), and screening of a combinatorial antibody library (Huse et al., Science, 246: 1275, 1989).
Further, as an alternative method, also acceptable is a method in which a mammal is immunized with insect cells per se in which CX3CR1 is expressed, hybridomas are prepared from lymphocytes of the mammal, and screening of the produced antibodies is performed by using mammal cells in which CX3CR1 is expressed (cells showing low cross immunity with the insect cells and not bound with antibodies directed to proteins derived from the insect cells). Further, they can also be prepared by the method described in Japanese Patent Laid-open No. 2002-345454.
Screening for antibodies that inhibit the interaction of fractalkine and CX3CR1 can be performed by the screening method described later.
<3> CX3CR1 Antagonist
The present invention was accomplished on the basis of the finding that antibodies inhibiting the interaction of fractalkine and CX3CR1 are useful for treatment of inflammatory diseases associated with the fractalkine-CX3CR1 cell infiltration system and caused by excessive NO production by the iNOS activity or inflammatory cells. Therefore, compounds inhibiting the interaction of fractalkine and CX3CR1 and the function of CX3CR1, the CX3CR1 antagonists, can also be used in the present invention. The CX3CR1 antagonists are not particularly limited so long as compounds having the aforementioned action are used, and they may be known or novel compounds. Further, they may be compounds obtained by the screening method described later.
In the present specification, the “compounds” include expression products of a gene library, synthetic low molecular compound library, nucleic acids (oligo DNA, oligo RNA), synthetic peptide library, substances released from bacteria, cell (microorganisms, plant cells, animal cells) extracts, cell (microorganisms, plant cells, animal cells) culture supernatant, purified or partially purified polypeptides, extracts derived from marine organisms, plants, animals and so forth, soil and random phage peptide display library. Specific examples include the compounds described in International Patent Publications WO03/018549, WO00/09511 and WO02/076990, and so forth. Known compounds can be produced by a production method known per se, or when they are natural compounds, they can be obtained by an extraction method known per se or a purification method known per se, or when they are commercially available, they can be purchased. Further, derivatives of known compounds can be obtained by modification by chemical, physical and/or biochemical means.
<4> Screening Method for Antibodies Inhibiting Interaction of Fractalkine and CX3CR1
Antibodies or CX3CR1 antagonists inhibiting the interaction of fractalkine and CX3CR1 can be screened for on the bases of whether CX3CR1-positive cells migrate to cells expressing fractalkine or membrane-bound fractalkine. A specific method for screening on the basis of whether CX3CR1-positive cells migrate is described below. However, the present invention is not limited to this method.
Migration to fractalkine can be measured by using, for example, a transwell culture insert (Coaster).
Cells not expressing fractalkine, for example, ECV304 cells, are cultured on a transwell culture insert to form a single cell layer on the surface of the culture insert. Fractalkine is diluted with a migration solution (for example, RPMI-1640:M199=1:1, 0.5% BSA, 20 mM HEPES, pH 7.4) to an appropriate concentration, preferably a concentration of 10 nM, and added to a 24-well plate. The transwell culture insert on which ECV304 cells are cultured is attached to the 24-transwell, and an appropriate number, preferably 106, of peripheral blood monocytes suspended in the migration solution are added to the transwell culture insert. The cells are cultured under an appropriate condition, preferably, at 37° C. for 4 hours, then cells that migrate to the well plate through the ECV304 cells are collected and identified on the basis of cell surface markers or intracellular antigens. Preferably, they are stained with fluorescence by using antibodies labeled with fluorescence directed to a cell surface marker or intracellular antigen, and then quantified by using the FACS calibur.
If migration of killer lymphocytes, preferably cells expressing perforin and granzyme B or CX3CR1, more preferably cells expressing CX3CR1, is inhibited when antibodies that bind to CX3CR1 or fractalkine is added to the migration solution, the antibodies are determined to inhibit the interaction of fractalkine and CX3CR1.
Further, by expressing membrane-bound fractalkine in ECV304 cells and measuring peripheral blood monocytes that migrate to other chemokines such as MIP-1β, whether an antibody inhibits the interaction of fractalkine and CX3CR1 can also be determined.
<5> Inhibition of iNOS Production
In the present specification, the expression “inhibition of iNOS production” or “iNOS production is inhibited” means that the expression level of mRNA for iNOS is suppressed, or the production amount of iNOS protein is suppressed. Inhibition of iNOS production can be measured by any of real time PCR, Western blotting, ELISA (solid phase enzyme-linked immunosorbent assay) and iNOS enzyme activity measurement. For example, the real time PCR is specifically performed as follows. Total RNA is purified from tissues or cells in a conventional manner, and cDNA is prepared by using a reverse transcriptase and suitable primers. From the prepared cDNA, each molecule can be specifically amplified by using primers specific to each molecule and a DNA polymerase. An amplification curve for each molecule can be monitored by incorporating an a suitable fluorescent dye into the molecule when it is amplified and using a specific apparatus (PRISM 7700 Sequence Detector (Applied Biosystems) etc.). The mRNA expression level of each molecule in tissues and cells can be quantitatively measured by correcting each molecule using an internal standard gene (glyceraldehyde-3-phosphate dehydrogenase gene etc.).
<6> Use of Antibody or CX3CR1 Antagonist Inhibiting Interaction of Fractalkine and CX3CR1
The present invention provides a therapeutic agent for an inflammatory disease containing an antibody or a CX3CR1 antagonist inhibiting the interaction of fractalkine and CX3CR1. In the aforementioned therapeutic agent, the aforementioned antibody preferably an antibody that binds to fractalkine. When the therapeutic agent of the present invention containing the antibody is applied to humans, the following embodiments are preferred.
A monoclonal antibody prepared by using an animal other than human, for example, a mouse monoclonal antibody prepared by using mouse as an animal to be immunized, is often recognized as a foreign protein and often causes an immune response against a monoclonal antibody, when it is administered to a human. One means for avoiding this problem is a chimeric antibody, that is, an antibody consisting of an antigen binding region derived from a mouse monoclonal antibody and the other regions derived from a human antibody. The antibodies inhibiting the interaction of fractalkine and CX3CR1 used in the present invention also include chimeric antibodies. Examples of chimeric antibodies include a chimeric antibody using the entire variable region of a mouse monoclonal antibody as the antigen binding region (Morrison et al., Proc. Natl. Acad. Sci. USA, 81: 6851, 1985; Takeda et al., Nature, 314: 452, 1985) and a chimeric antibody using a human-derived framework region and a hypervariable region derived from a mouse monoclonal antibody in combination as the antigen binding region (Teng et al., Proc. Natl. Acad. Sci. USA, 80: 7308-12, 1983; Kozbar et al., Immunol. Today, 4: 7279, 1983). However, the present invention is not limited to these examples.
Further, the antibodies inhibiting the interaction of fractalkine and CX3CR1 referred to in the present specification also include a fragment of an antibody specifically binding to CX3CR1 or fractalkine, for example, Fab or (Fab′)2 fragment.
The therapeutic agent of the present invention can be administered to patients who need treatment of inflammatory diseases associated with the fractalkine-CX3CR1 cell infiltration system and caused by excessive NO production by the iNOS activity or inflammatory cells, specifically, inflammatory bowel diseases (in particular, ulcerative colitis, Crohn's disease), psoriasis, atopic dermatitis, asthma, arteriosclerosis, tissue damage caused by ischemic reperfusion, acute respiratory distress syndrome, and so forth. The inflammatory diseases may be autoimmune diseases or other inflammatory diseases. Further, the inflammatory diseases may be nephritis, myocarditis, autoimmune hepatopathy, multiple sclerosis, rheumatism or other inflammatory diseases.
The therapeutic agent of the present invention can be administered in a conventional manner such as injection (subcutaneous, intravenous injections etc.).
The form of the therapeutic agent is suitably selected depending on the administration method and may be a pharmaceutical composition using pharmaceutically acceptable carriers in combination. Examples of the pharmaceutical composition suitable for injection include sterilized aqueous solution (when the ingredients are water-soluble), dispersion, or and sterilized powder used to immediately prepare sterilized injection solution or dispersion. All the pharmaceutical compositions suitable for injection must be sterilized and have fluidity enabling easy injection operation. These compositions must be stable under production and storage conditions and must be protected from actions of contaminating microorganisms such as bacteria and fungi. Examples of the carriers include water, ethanol, polyols (for example, glycerol, propylene glycol, polyethylene glycol etc.), solvents or dispersion media comprising an appropriate mixture of these. Suitable fluidity can be maintained by, for example, using a coating of lecithin or the like to maintain a required grain size in the case of dispersions or using a surfactant. Protection from actions of microorganisms can be implemented by using various antibacterial agents and antifungal agents such as paraben, chlorobutanol, phenol, ascorbic acid and thimerosal. In many cases, the composition preferably contains an isotonic agent, for example, sugars, polyalcohols such as mannitol and sorbitol, sodium chloride, and so forth. Sustained absorption of the composition for injection can be achieved by mixing an agent delaying absorption such as aluminum monostearate and gelatin in the composition.
A solution for injection can be prepared by mixing a required amount of the antibody inhibiting the interaction of fractalkine and CX3CR1 and one or a mixture of the aforementioned components in a suitable solvent if necessary and then subjecting the mixture to sterilization filtration. In general, a dispersion is prepared by mixing an active compound in a sterilized medium containing a basic dispersion medium and other required components selected from those mentioned above. Preferred methods for preparing sterilized powder used for preparation of a sterilized injection solution are vacuum drying and lyophilization, and powders containing the active ingredient and desired additional components subjected to sterilization filtration beforehand can be obtained by these methods.
Dose of the therapeutic agent of the present invention may vary depending on the selected antibody, object of administration, age, sex and susceptibility to drugs of patient, administration method, history of the disease and so forth, and may be changed by physician's discretion. However, the suitable dose range is, for example, about 0.01 to 30 mg, preferably about 0.1 to 10 mg, per kg of body weight of the patient. Taking into account that efficiency of the administration routes varies, the required dose is expected to change in a wide range. For example, it is expected that oral administration requires a dose higher than that for administration by intravenous injection. Such changes in the dose level can be adjusted by using a standard empirical optimization procedure well understood in this field.
Further, an immunotoxin containing an antibody directed to CX3CR1 and a cytotoxic substance bound to the antibody may be prepared.
Examples of the toxic substance include saporin, ricin, Pseudomonas exotoxin, diphtheria toxin, chemotherapeutic agents and so forth. The antibody and the toxic substance can be bound by a conventional method used for preparation of immunotoxins. Such an immunotoxin specifically inhibits growth of CX3CR1 expressing cells.
When a therapeutic agent for inflammatory diseases containing the CX3CR1 antagonist is applied to humans, the following embodiments are preferred. The CX3CR1 antagonist may form a salt, and examples thereof include salts with pharmaceutically acceptable acids or bases and so forth. Accordingly, the CX3CR1 antagonist or a salt thereof can be used for treatment of inflammatory diseases associated with the fractalkine-CX3CR1 cell infiltration system and caused by excessive NO production by the iNOS activity or inflammatory cells, specifically, inflammatory bowel diseases (in particular, ulcerative colitis and Crohn's disease), psoriasis, atopic dermatitis, asthma, arteriosclerosis, tissue damage caused by ischemic reperfusion, acute respiratory distress syndrome, and so forth. The obtained substances per se can be solely used, or they can also be used as a pharmaceutical composition by mixing them with a pharmaceutically acceptable carrier. The proportion of the active ingredient to the carrier in such a case can be changed in the range of 1 to 90% by weight. Further, the therapeutic agent can be administered via any of oral or parenteral administration routes (for example, intravenous injection, intramuscular injection, subcutaneous administration, rectal administration or percutaneous administration).
Therefore, a pharmaceutical composition containing the CX3CR1 antagonist or a salt thereof is prepared in a suitable dosage form depending on the administration route, and specific examples of the dosage form include oral agents such as tablet, capsule, granule, powder and syrup, and parenteral agents such as injection, drip infusion, liposome and suppository. These preparations can be produced in a conventional manner using usually used excipients, extenders, binders, wetting agents, disintegrating agents, surfactants, lubricants, dispersing agents, buffers, preservatives, dissolving aids, antiseptics, flavoring agents, soothing agents, stabilizers, and so forth. Examples of usable nontoxic additives mentioned above include lactose, fructose, glucose, starch, gelatin, magnesium stearate, methylcellulose or salts thereof, ethanol, citric acid, sodium chloride, sodium phosphate and so forth.
Administration form and required dose range thereof depend on selection of the obtained compounds, object of administration, administration route, property of the preparation and conditions of patient as well as physician's discretion. However, the suitable dose range is about 1.0 to 1,500 μg, preferably about 10 to 500 μg, per kg of body weight of the patient. Taking into account that efficiency of the administration route varies, the required dose is expected to be changed in a wide range. For example, it is expected that oral administration requires a dose higher than that for administration by intravenous injection. Such changes in the dose level can be adjusted by using a standard empirical optimization procedure well understood in this field.
In the present specification, “treatment” generally means to obtain a desired pharmacological effect and/or physiological effect. The effect may be prophylactic in view of completely or partially preventing a disease and/or a symptom, or may be therapeutic in view of partially or completely curing a disease and/or adverse effect of the disease. In the present specification, “treatment” includes arbitrary treatments of diseases in mammals, in particular, humans, for example, the following treatments (a) to (c):
(a) Prevention of onset of a disease or symptom in a patient who may have a predisposition of the disease or symptom, but is not yet diagnosed to have the predisposition;
(b) Inhibition of a symptom of a disease, that is, prevention of progression of the symptom;
(c) Amelioration of a symptom of a disease, that is, induction of regression of the disease or symptom.
Since the antibody or the CX3CR1 antagonist inhibiting the interaction of fractalkine and CX3CR1 used in the present invention has an action of inhibiting iNOS production, an iNOS production inhibitor containing the CX3CR1 antagonist as an active ingredient is also provided. The iNOS production inhibitor may be prepared as a composition like the aforementioned therapeutic agent, and can be administered to a patient who needs inhibition of iNOS production in the same manner as that for the aforementioned therapeutic agent.
Hereafter, the present invention will be explained in more detail with reference to examples. However, these are mentioned as embodiments, and the scope of the present invention is not limited at all by these examples. The abbreviations used in the following description are according to those conventionally used in this field.
Example 1
Effect of Anti-Fractalkine Antibody (5H8-4) in Mouse Inflammatory Bowel Disease Model Transfused with CD4-Positive and CD45RB Strongly-Positive (CD4+CD45RBhigh) T Lymphocytes
(1) Preparation of Anti-Fractalkine Antibody (5H8-4)
The anti-fractalkine antibody (5H8-4) was prepared by the following method (Japanese Patent Laid-open No. 2002-345454). Mouse fractalkine (R&D) was used as an antigen. The antigen was mixed with TiterMax adjuvant, Armenian hamsters were immunized with the mixture, and booster immunizations were performed thereafter with the antigen alone. The antibody titer in the serum was measured by ELISA. Lymphocytes were isolated from the Armenian hamsters in which the antibody titer increased, the lymphocytes and P3 myeloma cells were mixed at a ratio of 5:1, and the cells were fused by using PEG (Boehringer). The hybridomas were cultured on a 96-well plate for one week by using RPMI-1640/10% FCS/HAT/10% Origen HCF (ISGN). Then, ELISA was performed for the culture supernatant to identify positive wells. The hybridomas producing anti-mouse fractalkine antibodies were subjected to limiting dilution twice for cloning. The monoclonal antibodies were purified by using a protein A column from the ascites prepared by inoculating the hybridomas to SCID mice to which the incomplete Freund's adjuvant was administered. The neutralization activity was determined by using inhibition of migration of CX3CR1 expressing cells to mouse fractalkine as an index to obtain a neutralizing antibody (5H8-4). The hybridoma producing the neutralizing antibody was designated as Ham @mFKN5H8-4.
(2) Method
As for preparation of an inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive (CD4+CD45RBhigh) T lymphocytes, reference was made to Powrie et al., Int. Immunol., 5, 1461-1471, 1993. The spleens were removed from 8- to 10-week old female Balb/c mice (Charles River Laboratories Japan, Inc.), and the tissues were ground on a cell strainer (PharMingen) having a pore diameter of 100 μm to separate spleen cells. The separated spleen cells, 5 ml of ammonium chloride solution (0.75% ammonium chloride, 16 mM Tris buffer, pH 7.4) was added per each spleen and the mixture was left at room temperature for 15 minutes to lyse erythrocytes. To the spleen cell solution, PBS was added in a volume of 2 times and the mixture was centrifuged at 1500 rpm for 5 minutes, to collect the precipitates. CD4 T lymphocytes were purified from the separated spleen cells by using CD4 T Cell Isolation Kit (Milteny). To separate CD4-positive and CD45RB strongly-positive T lymphocytes, the purified CD4 T lymphocytes were subjected to double staining using phycoerythrin (PE)-labeled anti-CD4 antibody (eBioscience) and fluorescein isothiocyanate (FITC)-labeled anti-CD45RB antibody (eBioscience). After the double staining, CD4-positive and CD45RB strongly-positive cells were sorted by using FACSAria (Becton-Dickinson) to collect the objective cells. The collected cells were washed with PBS and then suspended in PBS at a cell density of 2×106 cells/ml. The CD4-positive and CD45RB strongly-positive cells prepared above were transfused into the peritoneal cavities of 8- to 10-week old female SCID mice (Clea Japan, Inc.) in a volume of 200 μl each, that is, 4×105 cells/mouse. Seven SCID mice in each group transfused with the CD4-positive and CD45RB strongly-positive cells were given with 500 μg of a control antibody (hamster IgG) or 500 μg of the anti-fractalkine antibody (5H8-4) (antibody in PBS) once every three days from two weeks after the cell transfusion. The administration was performed from the caudal vein. Further, as a negative control group, four SCID mice transfused with mouse CD4 T lymphocytes (total CD4) that were purified by using CD4 T cell Isolation Kit (Milteny) and not separated on the basis of the expression level of CD45RB in an amount of 1.2×106 cells/mouse were used. Two weeks after the administration of each antibody, autopsy was performed, and evaluation was performed on the basis of body weight loss, scores of stool consistency in the large intestine, development of large intestine hypertrophy, iNOS mRNA expression analysis and pathological observation. As the stool consistency scores, the stool consistency scores used for analysis of dextran sulfate sodium-induced colitis (Cooper et al., Lab. Invest., 69, 238-249, 1993) shown in Table 1 were used.







TABLE 1







Stool consistency scores











Stool consistency






Score 0
Normal



Score 1
Loose stool (shape is substantially normal)



Score 2
Loose stool (shape is maintained)



Score 3
Loose stool (shape is abnormal)



Score 4
Diarrhea, stool attaches around anus









Further, for large intestine hypertrophy, a site about 1.5 cm from the anal region was measured by using Dial Thickness Gauge (Peacock) after removing intestinal contents. Further, the large intestine was subjected to morphological observation and histopathological observation based on Mayer's hematoxylin eosin staining of tissue sections.
Further, expressions of mRNAs for iNOS and so forth were analyzed by real time PCR using, as a template, cDNA obtained by purifying total RNA (500 ng) from the large intestine using RNeasy Mini Kit (QIAGEN) and reverse transcribing it using AMV reverse transcriptase (TAKARA) and a random hexamer (TAKARA). The real time PCR was performed for a reaction mixture prepared by mixing various primers with reagents of QuantiTect SYBR Green PCR Kit (Qiagen) and uracil-DNA-glycosylase (Invitrogen) by using ABI PRISM 7700 Sequence Detector (Applied Biosystems). PCR was performed by reactions at 50° C. for 2 minutes and at 95° C. for 15 minutes and 35 cycles of reactions at 95° C. for 15 seconds and at 60° C. for 1 minute. The used primer sets are as follows.









TABLE 2







SEQ ID 


Primer
Sequence
NO:

















miNOS sense
5′-AGCTGAACTTGAGCGAGGAG-3′
1


miNOS anti-sense
5′-TGCCCCATAGGAAAAGACTG-3′
2


mfractalkine (FKN) sense
5′-GGCAAGATGACCTCACGAAT-3′
3


mfractalkine (FKN) anti-sense
5′-CTGTGTCGTCTCCAGGACAA-3′
4


mIFN-γ sense
5′-GCTTTAACAGCAGGCCAGAC-3′
5


mIFN-γ anti-sense
5′-GGAAGCACCAGGTGTCAAGT-3′
6


mTNF α sense
5′-CCAGTGTGGGAAGCTGTCTT-3′
7


mTNF α anti-sense
5′-AAGCAAAAGAGGAGGCAACA-3′
8


mIL-4 sense
5′-GGCATTTTGAACGAGGTCAC-3′
9


mIL-4 anti-sense
5′-AAATATGCGAAGCACCTTGG-3′
10


mPerforin sense
5′-TGCAAGCAGAAGCACAAGTT-3′
11


mPerforin anti-sense
5′-TGTGTGTTCACTGGGAAGGA-3′
12


mGranzymeB (GrB) sense
5′-CCATCGTCCCTAGAGCTGAG-3′
13


mGranzymeB (GrB) anti-sense
5′-GCTGGTCCTTGTGAATGGAT-3′
14


mFasL sense
5′-CTGTGGCTACCGGTGGTATT-3′
15


mFasL anti-sense
5′-GTTCTGCCAGTTCCTTCTGC-3′
16


mFas sense
5′-GGAGACAGGATGACCCTGAA-3′
17


mFas anti-sense
5′-TTCAGCAATTCTCGGGATGT-3′
18









(3) Results

The body weight loss was suppressed in the anti-fractalkine antibody (5H8-4) administration group compared with the control antibody administration group (FIG. 1). Further, the consistency scores of stool in the large intestine and large intestine hypertrophy were improved in the anti-fractalkine antibody (5H8-4) administration group compared with the control antibody administration group (FIG. 2). As for the morphological observation of the large intestine sites, hypertrophy was observed at sites from the colon to the rectum in the control antibody administration group, and improvement was observed by administration of the anti-fractalkine antibodies (5H8-4) (FIG. 3). In tissue section staining, a very large number of leukocytes (T lymphocytes, monocytes, macrophages etc.) infiltrated into the large intestine mucosal layer, and disappearance of goblet cells producing mucus, and damage and hyperplasia of the large intestine epithelial tissues were observed in the control antibody group. In contrast, in the anti-fractalkine antibody (5H8-4) administration group, leukocyte infiltration was inhibited, and large intestine epithelial cells were hardly damaged (FIG. 4). Further, as for mRNA expression, expression of iNOS mRNA increased in the control antibody administration group, but the expression was markedly inhibited by the anti-fractalkine antibodies (5H8-4). Furthermore, expressions of mRNAs for cytotoxic factors such as perforin, Fas and FasL and cytokines such as IFNγ and TNFα also increased in the control antibody administration group. In contrast, inhibition of these expressions was observed in the anti-fractalkine antibody (5H8-4) administration group (FIG. 5). The above results revealed that the fractalkine-CX3CR1 pathway played an important role in the inflammatory bowel disease model transfused with CD4-positive and CD45RB strongly-positive (CD4+CD45RBhigh) T lymphocytes. It was inferred that the action inhibited excessive NO production by inhibiting iNOS production and ameliorated tissue damages. That is, it was suggested that inhibition of iNOS production based on the inhibition of the interaction of fractalkine and CX3CR1 was a useful treatment system for inflammatory bowel diseases.
Example 2
Effect of Anti-Fractalkine Antibody (5H8-4) in Mouse Oxazolone-Induced Inflammatory Bowel Disease Model
(1) Method
As for the mouse oxazolone-induced inflammatory bowel disease model, reference was made to Iijima et al., J. Exp. Med., 199, 471-482, 2004. The abdomens of 8 to 10-week old male Balb/c mice (Charles River Laboratories Japan, Inc.) were shaved in an about 2-cm square. To each mouse, 150 μl each of 100% ethanol solution containing 3% 4-ethoxymethylene-2-phenyl-2-oxazolin-5-one (hereinafter referred to as oxazolone, Sigma) was applied. The animals were starved on the fourth day after the oxazolone sensitization, and on the fifth day, given an intestinal injection of 100 μl each of 50% ethanol/physiological saline containing 0.5% oxazolone at a site about 3 cm from the anus under diethyl ether anesthesia. As a negative control group, five normal Balb/c mice were given an intestinal injection of 100 μl each of 50% ethanol/physiological saline. To seven mice in each group given with the intestinal injection of oxazolone, 500 μg of a control antibody (hamster IgG) or 500 μg of the anti-fractalkine antibody (5H8-4) (antibody in PBS) was administered. The anti-fractalkine antibody (5H8-4) was administered on the fifth day after the sensitization (immediately before the intestinal injection of oxazolone). The antibody was administered from the caudal vein. The evaluation was performed for the evaluation items of Disease Activity Index (hereinafter referred to as DAI, stool consistency, blood content and body weight gain and loss were represented by scores, and DAI values were calculated), large intestine shortening, large intestine hypertrophy and pathological observation. As DAI, DAI used for evaluation of dextran sodium sulfate induced colitis (Cooper et al., Lab. Invest., 69, 238-249, 1993) shown in Table 3 was used.







TABLE 3







DAI











Body weight





loss
Stool consistency
Bloody stool





Score 0
0%
Normal
Normal


Score 1
0-5%
Loose stool (shape
Trace of




is substantially
blood in




normal)
stool


Score 2
 5-10%
Loose stool (shape
Bloody stool




is maintained)
(about half





of stool)


Score 3
10-15%
Loose stool (shape
Bloody stool




is abnormal)
(most of





stool)


Score 4
>20%
Diarrhea, stool
Bleeding




attaches around





anus









Further, since diarrhea and loose stool were observed from the second day after the intestinal injection of oxazolone, DAI was observed over time. The large intestine was subjected to morphological observation and histopathological observation based on Mayer's hematoxylin eosin staining of tissue sections.
(2) Results
Compared with the control antibody administration group, the anti-fractalkine antibody (5H8-4) administration group showed improved DAI from the second days after the intestinal injection of oxazolone (FIG. 6). Further, hypertrophy and shortening of the large intestine also improved in the anti-fractalkine antibody (5H8-4) administration group compared with the control antibody administration group (FIG. 7). In the morphological observation of the large intestine sites, hypertrophy was observed at sites from the colon to the rectum in the control antibody administration group, but improvement was observed by administration of the anti-fractalkine antibodies (5H8-4) (FIG. 8). In the tissue section staining, a very large number of leukocytes (T lymphocytes, monocytes, macrophages etc.) infiltrated into the large intestine mucosal layer, and disappearance of goblet cells producing mucus, and damage and hypertrophy were observed in the large intestine epithelial tissues in the control antibody group. In contrast, in the anti-fractalkine antibody (5H8-4) administration group, leukocyte infiltration was inhibited, and large intestine epithelial cells were hardly damaged (FIG. 9). It was expected from the above results that the fractalkine-CX3CR1 cell infiltration system played an important role also in the oxazolone-induced colitis model, and it was suggested that the fractalkine-CX3CR1 cell infiltration system was a useful treatment system for inflammatory bowel diseases.
Example 3
Effect of Anti-Fractalkine Antibody (#126) in Mouse Oxazolone-Induced Inflammatory Bowel Disease Model
(1) Preparation of Anti-Fractalkine Antibody (#126)
Mouse fractalkine (Genzyme) and Titer MaxTM Gold adjuvant were mixed, and then used to immunize Armenian hamsters two or more times, and the final immunization was further performed with the mouse fractalkine alone. The antibody titer in the serum was measured by ELISA using solid-phased fractalkine, and lymphocytes were isolated from Armenian hamsters in which the antibody titer increased. The lymphocytes and P3 myeloma cells were mixed at a ratio of 5:1, and cell fusion was performed by using PEG (Rosh). The hybridomas were cultured on a plate for one week by using RPMI-1640/10% FCS/HAT/10% Origen HCF (ISGN). Then, the culture supernatant was assayed by ELISA using solid-phased fractalkine to identify positive wells. The hybridomas producing the anti-fractalkine antibodies were cloned by performing limiting dilution twice. By using a protein A column, the monoclonal antibodies were purified from the ascites prepared by inoculating the hybridoma to SCID and nude mice to which pristine was administered. The neutralization activity of the obtained antibodies was determined by using inhibition of migration of CX3CR1 expressing cells to mouse fractalkine as an index, and the #126 antibody having neutralization activity was obtained. The hybridoma producing the neutralizing antibody was designated as Ham @mFKN#126.1.1.
(2) Method
Investigation was performed in the same manner as that used in Example 2. The evaluation items were large intestine shortening and hypertrophy. To seven mice in each group given with intestinal injection of oxazolone, 500 μg of a control antibody (hamster IgG) or 500 μg of the anti-fractalkine antibody (#126) (antibody in PBS) was administered.
(3) Results
Like the 5H8-4 anti-fractalkine antibody, the #126 anti-fractalkine antibody improved large intestine shortening and hypertrophy compared with the control antibody (FIG. 10). These results strongly suggested that inhibition of the fractalkine-CX3CR1 cell infiltration system was useful for treatment of inflammatory bowel disease since two different types of anti-fractalkine antibodies exhibited effects in the oxazolone-induced colitis model.
Example 4
Expression of iNOS in ConA-Induced Hepatitis and Effect of Anti-Fractalkine Antibody (5H8-4) on iNOS Production
(1) Method
To four C57BL/6 mice mouse in each group, 500 μg of a control antibody (hamster IgG) or 500 μg of the anti-fractalkine antibody (5H8-4) (antibodies in PBS) was intravenously administered, and then immediately 12 mg/kg of concanavalin A (ConA, Sigma Aldrich) was intravenously administered. The liver was removed two hours later, and RNA was extracted. As a negative control group, there were provided four C57BL/6 mice to which PBS (phosphate buffer) was intravenously administered. The expression of mRNA for iNOS was measured by collecting RNA, synthesizing cDNA, and measuring it by real time PCR in the same manner as that used in Example 1. Further, 12 hours after the intravenous administration of the control antibody or the anti-fractalkine antibody and ConA, or PBS for the negative control group, the liver was removed, and frozen tissue sections were prepared. Immunohistologic staining was performed with the anti-iNOS antibodies and the anti-CX3CR1 antibodies, and iNOS and CX3CR1-positive cells were counted.
(2) Results
The expression of mRNA for iNOS increased by the administration of ConA was markedly decreased by the administration of the anti-fractalkine antibody. Further, expressions of mRNAs for cytotoxic factors such as granzyme B and Fas and cytokines such as IFNγ, TNFα and IL-4 were increased by the administration of ConA, and these expressions were decreased by the administration of the anti-fractalkine antibody (5H8-4) (FIG. 11). Further, the results of immunohistologic staining showed that iNOS positive inflammatory cells were increased by the administration of ConA, and markedly decreased by the administration of the anti-fractalkine antibody (FIG. 12). Further, CX3CR1-positive inflammatory cells were also increased by the administration of ConA, and markedly decreased by the administration of the anti-fractalkine antibody (5H8-4) (FIG. 12). The above results revealed that, by inhibiting the interaction of fractalkine and CX3CR1, expression of mRNA for iNOS was inhibited in the liver of ConA-induced hepatitis, and the iNOS production was inhibited in inflammatory cells, and thus it was suggested that tissue damage in the liver was ameliorated by inhibition of excessive NO production by inflammatory cells.
Example 5
Analysis of CX3CR1 and iNOS Expressing Cells in ConA-Induced Hepatitis
The results of immunohistologic staining were analyzed in detail. Most of the CX3CR1-positive cells were small and round, and had a horseshoe-shaped nucleus and a small amount of cytoplasm. They existed adjacent to the portal vein, central vein and sinusoid, and a part of them were observed also in the peripheries of necrotic regions. Most of the iNOS-positive cells were largely extended, and had a horseshoe-shaped nucleus and a large amount of cytoplasm. They existed adjacent to the sinusoid and were also observed in necrotic regions in addition to their peripheries, but not in the vicinity of the portal vein or central vein. Since differences were observed between CX3CR1-positive cells and iNOS-positive cells in their morphology and localization as described above, characteristics of CX3CR1-positive cells and iNOS-positive cells were analyzed in detail.
(1) Method
In the same manner as that used in Example 4, frozen tissue sections were prepared by using the liver obtained 12 hours after intravenous administration of ConA (ConA-induced hepatitis liver tissue). Double fluorescence staining was performed with the anti-CX3CR1 antibody or the anti-iNOS antibody (BD Bioscience) and the anti-BM8 antibody (BMA), the anti-CD11b antibody (eBioscience) or the anti-MCP-1 antibody (Gengyme Techne), and BM8, CD11b and MCP-1 positive rates in the CX3CR1-positive cells and iNOS-positive cells were measured.
The aforementioned anti-CX3CR1 antibody was prepared in rabbits by using a mouse CX3CR1C-terminus peptide (CSILSSFTHYTSEGDGSLLL (SEQ ID NO: 31)) as an antigen. Specifically, they were obtained as follows. A synthetic peptide of SEQ ID NO: 31 was bound to KLH, and used to immunize rabbits (JW) in an amount of 250 μg/rabbit at one time with an adjuvant. As the adjuvant, the complete Freund's adjuvant was used only for the initial immunization, and the incomplete Freund's adjuvant was used for the other remaining immunizations. The immunization was performed five times in total. The increase in the antibody titer was confirmed by ELISA by using a solid-phased peptide, and the serum was collected. Affinity purification was performed by using the peptide having the aforementioned sequence bound to Thiopropyl Sepharose 4B (Amersham Bioscience) to obtain the anti-CX3CR1 antibody from the collected serum.
Further, CX3CR1-positive cells in the peripheral blood (PBL) and bone marrow cells of 9-week old male C57BL/6 mice were cultured with M-CSF (50 ng/ml) for five days, and CX3CR1-positive cells among macrophages (BMMφ) differentiated from the bone marrow cells were analyzed by flow cytometry (FACS) for F4/80 specific to macrophages and monocytes and Ly6C, a surface marker of immature bone marrow system cells, by using anti-F4/80 antibody (CALTAG) and anti-Ly6C antibody (BMA). Further, tissue staining of ConA-induced hepatitis liver tissues with the anti-Ly6C antibody and tissue staining of ConA-induced hepatitis liver tissues infiltrated with fluorescence-labeled macrophages with the anti-MCP-1 antibody were performed.
(2) Results
Representative staining images are shown in FIG. 13. In the figure, letters at the left and top of the photographs represent the markers recognized by the antibodies used in the fluorescence staining. The length of the bar is 20 μm. The measurement results for the positive rate of each marker are shown in FIG. 14. In the figure, BM8+ denotes BM8 positive, CD11b+ denotes CD11b positive, and MCP1+ denotes MCP-1 positive.
The CX3CR1-positive cells comprised 68.9±2.7% (n=3) of small and round CD11b-positive cells, and 53.4±2.0% (n=3) of large and extended BM8-positive cells. On the other hand, the iNOS-positive cells comprised 81.6±1.8% (n=3) of large and extended BM8-positive cells, and 12.6±3.0% (n=3) of CD11b-positive cells. Therefore, it was revealed that the CX3CR1-positive cells were not necessarily iNOS-positive cells, and a part of them were expressed in another cell group. It has been recently reported that CCR2 is involved in infiltration of iNOS producing cells in a bacterial infection model mouse (Non-patent document 13). Accordingly, expression of MCP-1, a ligand of CCR2, was analyzed. MCP-1-positive cells were small and round like the CX3CR1-positive cells. MCP-1 was expressed in 72.5±3.7% (n=3) of the CX3CR1-positive cells, and most of the MCP-1-positive cells were CX3CR1-positive. Therefore, it was revealed that the CX3CR1-positive cells were major cells among the cells expressing MCP-1 in ConA-induced hepatitis. Further, as expected from the morphological differences between the MCP-1-positive cells and iNOS-positive cells, MCP-1 was expressed in only 14.6±2.2% (n=3) of the iNOS-positive cells, and they were hardly overlapped with each other. Therefore, it was found that most of the iNOS-positive cells were not CX3CR1/MCP-1-positive cells. Interestingly, iNOS-positive cells and MCP-1-positive cells existed adjacent to each other at a high frequency in the sinusoidal vessels and necrotic lesions in the liver.
The results of the analysis of CX3CR1-positive cells based on FACS are shown in FIG. 15. The results of the tissue staining are shown in FIG. 16.
As a result of the analysis of the CX3CR1-positive cells by FACS using peripheral blood (PBL), CX3CR1 was expressed in the F4/80-positive monocytes, and the expression level was high in the Ly6C− mature monocytes and low in the Ly6C+ immature monocytes. As a result of the tissue staining of the liver obtained 12 hours after the administration of ConA with Ly6C, which is a surface marker of immature bone marrow system cells, it was suggested that iNOS-positive and F4/80-positive cells were Ly6C-positive, and were derived from immature monocytes. Subsequently, bone marrow cells of 9-week old male C57BL/6 mice were cultured with M-CSF (50 ng/ml) for five days to obtain macrophages (BMMφ) differentiated from bone marrow cells. The adhered BMMφ macrophages were collected with 1 mM EDTA/PBS and analyzed by FACS. As a result, they were CX3CR1hi F4/80+Ly6C−/low like the peripheral blood mature monocytes. Then, BMMφ macrophages were labeled with fluorescence by using 10 μM CFSE, 2.5×106 cells/250 μl were intravenously injected to mice, ConA (15 mg/kg) was further intravenously injected ten minutes later, and the liver was collected 12 hours later for examination of infiltration. Infiltration of BMMφ to the liver was markedly increased by the administration of ConA. Further, the infiltrated fluorescence-labeled cells produced MCP-1 because of the administration of ConA. iNOS was not expressed in the fluorescence-labeled cells and derived from the host.
The above results suggested that CX3CR1-positive mature monocytes infiltrated into the inflammation sites upon inflammation to express MCP-1 and induce infiltration of iNOS producing immature monocytes into the inflammation sites, and thereby cause pathological conditions.
Example 6
Expressions of Chemokines in ConA-Induced Hepatitis and Effect of Anti-Fractalkine Antibody (5H8-4) on Expressions of Chemokines
(1) Method
Expressions of mRNAs for chemokines were measured by real time PCR in the same manner as that used in Example 1 by using cDNA derived from the liver two hours after intravenous administration of ConA prepared in Example 4. The primer sets used were as follows. The glyceraldehyde-3-phosphate dehydrogenase (G3PDH) gene was used as a control gene.









TABLE 4







SEQ ID 


Primer
Sequence
NO:







mMCP-1 sense
5′-AGGTCCCTGTCATGCTTCTG-3′
19


mMCP-1 anti-sense
5′-TCATTGGGATCATCTTGCTG-3′
20


mKC sense
5′-CTTGAAGGTGTTGCCCTCAG-3′
21


mKC anti-sense
5′-TGGGGACACCTTTTAGCATC-3′
22


mMIP-2 sense
5′-TCCAGAGCTTGAGTGTGACG-3′
23


mMIP-2 anti-sense
5′-GCCTTGCCTTTGTTCAGTATC-3′
24


mIP-10 sense
5′-TGAATCCGGAATCTAAGACCA-3′
25


mIP-10 anti-sense
5′-GAGGCTCTCTGCTGTCCATC-3′
26


mMIP-1α sense
5′-ACCATGACACTCTGCAACCA-3′
27


mMIP-1α anti-sense
5′-GATGAATTGGCGTGGAATCT-3′
28


mMIP-1β sense
5′-CCCACTTCCTGCTGTTTCTC-3′
29


mMIP-1β anti-sense
5′-CTCACTGGGGTTAGCACAGA-3′
30









(2) Results

The results are shown in FIG. 17. In the figure, “normal” denotes a negative control, “control” denotes a control antibody administration group, and “anti-FKN” denotes an anti-fractalkine administration group.
Two hours after the administration of ConA, expressions of mRNAs for MCP-1, KC, MIP-2, IP-10, MIP-1α and MIP-1β increased in the liver. The expressions of mRNAs for these chemokines were decreased by the administration of the anti-fractalkine antibody. These results suggested that production of many types of chemokines was inhibited by inhibition of the interaction of fractalkine and CX3CR1, and thus the amplifying pathway of inflammatory cell infiltration and activation as the initial inflammation induction reactions extensively became not to function.
Example 7
Expressions of mRNAs for Cell Surface Markers, Cytokines, Chemokines, Cell Activation Molecules and Cytotoxic Molecules and Effect of Anti-Fractalkine Antibody (5H8-4) on Expressions of mRNAs for Cell Surface Markers, Cytokines, Chemokines, Cell Activation Molecules and Cytotoxic Molecules in Mouse Inflammatory Bowel Disease Model Transfused with CD4-Positive and CD45RB Strongly-Positive (CD4+CD45RBhigh) T Lymphocytes
(1) Method
Expressions of mRNAs for leukocyte markers, cytokines, chemokines and molecules involved in cell activation and tissue destruction were measured in more detail by TaqMan PCR in the same manner as that used in Example 1 using cDNA derived from the large intestine prepared in Example 1. The primer sets used were as follows.









TABLE 5







SEQ ID 


Primer
Sequence
NO:

















CD4 sense
5′-GGGCTGTGGCAGTGTCTACT-3′
32


CD4 anti-sense
5′-CTGGTTCACCCCTCTGGATA-3′
33


F4/80 sense
5′-TGCCTCCCTGACTTTCAAAT-3′
34


F4/80 anti-sense
5′-TGGCATTGCTGTATCTGCTC-3′
35


T-bet sense
5′-GGGAAGCTAAAGCTCACCAA-3′
36


T-bet anti-sense
5′-CCTCTGGCTCTCCATCATTC-3′
37


CD11c sense
5′-CTTATCGTGGGCAGCTCAGT-3′
38


CD11c anti-sense
5′-CCATTTGCTTCCTCCAACAT-3′
39


M-CSF receptor sense
5′-CGACTTCTTCAAGTGACTCCTTC-3′
40


M-CSF receptor anti-sense
5′-CTACGTCCCGGTGGATGC-3′
41


Ly-6G sense
5′-GATGGATTTTGCGTTGCTCT-3′
42


Ly-6G anti-sense
5′-GTCCAGAGTAGTGGGGCAGA-3′
43


IL-1β sense
5′-GCTGAAAGCTCTCCACCTCA-3′
44


IL-1β anti-sense
5′-AGGCCACAGGTATTTTGTCG-3′
45


IL-6 sense
5′-CAAAGCCAGAGTCCTTCAGAG-3′
46


IL-6 anti-sense
5′-GCCACTCCTTCTGTGACTCC-3′
47


IL-12α sense
5′-GCCAGGTGTCTTAGCCAGTC-3′
48


IL-12α anti-sense
5′-TCTTCAATGTGCTGGTTTGG-3′
49


IL-12β sense
5′-ATCCAGCGCAAGAAAGAAAA-3′
50


IL-12β anti-sense
5′-AATAGCGATCCTGAGCTTGC-3′
51


IL-23α sense
5′-CAACAGCCAGTTCTGCTTGC-3′
52


IL-23α anti-sense
5′-GATCCTCTGGCTGGAGGAG-3′
53


IL-17 sense
5′-TCCAGAAGGCCCTCAGACTA-3′
54


IL-17 anti-sense
5′-TGAGCTTCCCAGATCACAGA-3′
55


RANKL sense
5′-CATTTGCACACCTCACCATC-3′
56


RANKL anti-sense
5′-TCCGTTGCTTAACGTCATGT-3′
57


KC sense
5′-CTTGAAGGTGTTGCCCTCAG-3′
58


KC anti-sense
5′-TGGGGACACCTTTTAGCATC-3′
59


MIP-2 sense
5′-TCCAGAGCTTGAGTGTGACG-3′
60


MIP-2 anti-sense
5′-GCCTTGCCTTTGTTCAGTATC-3′
61


MCP-1 sense
5′-AGGTCCCTGTCATGCTTCTG-3′
62


MCP-1 anti-sense
5′-TCATTGGGATCATCTTGCTG-3′
63


MCP-3 sense
5′-CTGCTTTCAGCATCCAAGTG-3′
64


MCP-3 anti-sense
5′-CCCAGGGACACCGACTACT-3′
65


CXCR2 sense
5′-GCTCACAAACAGCGTCGTAG-3′
66


CXCR2 anti-sense
5′-AGGGCATGCCAGAGCTATAA-3′
67


CCR2 sense
5′-CTTTGCAACTGCCTCTTTCC-3′
68


CCR2 anti-sense
5′-TTCCCAGGAAGAGGTTGAGA-3′
69


MIP-1α sense
5′-ACCATGACACTCTGCAACCA-3′
70


MIP-1α anti-sense
5′-GATGAATTGGCGTGGAATCT-3′
71


MIP-1β sense
5′-CCCACTTCCTGCTGTTTCTC-3′
72


MIP-1β anti-sense
5′-CTCACTGGGGTTAGCACAGA-3′
73


CCR5 sense
5′-GCCAGAGGAGGTGAGACATC-3′
74


CCR5 anti-sense
5′-GCCAGAGGAGGTGAGACATC-3′
75


TARC sense
5′-TGCTTCTGGGGACTTTTCTG-3′
76


TARC anti-sense
5′-CATCCCTGGAACACTCCACT-3′
77


MDC sense
5′-TTCTTGCTGTGGCAATTCAG-3′
78


MDC anti-sense
5′-GCAGGATTTTGAGGTCCAGA-3′
79


CCR4 sense
5′-TGTCCTCAGGATCACTTTCAGA-3′
80


CCR4 anti-sense
5′-AGCAGGAGAAGCCAATGAGA-3′
81


IP-10 sense
5′-TGAATCCGGAATCTAAGACCA-3′
82


IP-10 anti-sense
5′-GAGGCTCTCTGCTGTCCATC-3′
83


I-TAC sense
5′-CAAGCAAGCTCGCCTCATA-3′
84


I-TAC anti-sense
5′-GCATGTTCCAAGACAGCAGA-3′
85


CXCR3 sense
5′-GTTCTGCTGGTCTCCAGAGG-3′
86


CXCR3 anti-sense
5′-TGCCACCACCACTACCACTA-3′
87


CD40 sense
5′-GTCGGCTTCTTCTCCAATCA-3′
88


CD40 anti-sense
5′-GCATCCGGGACTTTAAACC-3′
89


CD40L sense
5′-TGGATCTGTGCTTTTTGCTG-3′
90


CD40L anti-sense
5′-CCTTCTCCTTTGTTGCATCTC-3′
91


CD80 sense
5′-GCTGAACAGACCGTCTTCCT-3′
92


CD80 anti-sense
5′-GTTTGCAGAGCCAGGGTAGT-3′
93


CD86 sense
5′-TTCAGCAAAACCAAATGCAG-3′
94


CD86 anti-sense
5′-TGCACTTCTTATTTCAGGCAAA-3′
95


Class II sense
5′-TCTACACCTGCGTGGTTCAG-3′
96


Class II anti-sense
5′-GCCAACACAGAAGATGATGAAG-3′
97


TLR2 sense
5′-TAGGGGCTTCACTTCTCTGC-3′
98


TLR2 anti-sense
5′-CCAAAGAGCTCGTAGCATCC-3′
99


bFGF sense
5′-CCAACCGGTACCTTGCTATG-3′
100


bFGF anti-sense
5′-GTGCCACATACCAACTGGAG-3′
101


VEGF Receptor 2 sense
5′-CCAAGCTCAGCACACAGAAA-3′
102


VEGF Receptor 2 anti-sense
5′-TCAGAATCACGCTGAGCATT-3′
103


MMP-2 sense
5′-CCCCTGATGTCCAGCAAGTA-3′
104


MMP-2 anti-sense
5′-TGCGATGAGCTTAGGGAAAC-3′
105


MMP-9 sense
5′-AGACGACATAGACGGCATCC-3′
106


MMP-9 anti-sense
5′-GTGGTTCAGTTGTGGTGGTG-3′
107


MMP-14 sense
5′-CTGGGAAGGAATCCCTGAAT-3′
108


MMP-14 anti-sense
5′-CTGGGAAGGAATCCCTGAAT-3′
109









(2) Results

In the control antibody administration group, expressions of mRNAs for various leukocyte markers such as CD4, T-bet, F4/80, M-CSF receptor (M-CSF R), Ly-6G and CD11c increased (FIG. 18). These results suggested a possibility that the numerous infiltrated leukocytes in the control antibody administration group observed in the tissue section staining of Example 1 might be constituted by many types of leukocytes such as CD4+ T cells (in particular, Th1-type CD4+ T cells), monocytes/macrophages, neutrophils and dendritic cells. Further, since increases in expressions of mRNAs for chemokine-chemokine receptors such as KC, MIP-2, CXCR2, MCP-1, MCP-3, CCR2, MIP-1α, MIP-1β, CCR5, IP-10, I-TAC, CXCR3, TARC, MDC and CCR4 were observed in the control antibody administration group, it was inferred that the infiltrated leukocytes infiltrated via these chemokine-chemokine receptor mechanisms (FIGS. 19 and 20). Further, marked increases were also observed in expressions of mRNAs for a series of inflammatory cytokines such as IL-1β, IL-6, IL-12α, Il-12β, Il-23α, Il-17 and RANKL, proteases MMP-2, MMP-9 and MMP-14 involved in tissue destruction and further bFGF and VEGF Receptor 2 involved in neovascularization at inflammation sites in the control antibody administration group (FIGS. 21 and 22). Furthermore, since increases were observed in expressions of CD40 and TLR2, activation receptors of dendritic cells and so forth, CD40L, a molecule that is expressed in activated T cells and activates dendritic cells and so forth, molecules of T cell activation cosignal molecule group such as CD80 and CD86, of which expression is enhanced by activation of dendritic cells, and MHC Class II, a possibility was suggested that antigen-presenting cells such as T cells and dendritic cells were activated at lesion sites, and antigen-specific acquired immunity systems might be operating (FIG. 23). The expressions of mRNAs for the series of leukocyte markers, chemokine-chemokine receptors, cytokines, tissue destruction molecules, neovascularization related molecules and T cell/dendritic cell activation molecules were markedly inhibited by the administration of the anti-fractalkine antibodies (FIGS. 18 to 23). The above results suggested a possibility that by inhibition of the interaction of fractalkine and CX3CR1, production of inflammatory cytokines and chemokines was inhibited, thus the amplifying pathway of inflammatory cell infiltration and activation extensively became not to operate, and progression of pathological conditions in inflammatory bowel disease was prevented.
Example 8
Expressions of mRNAs for Cell Surface Markers, Cytokines, Chemokines, Cell Activation Molecules and Cytotoxic Molecules and Effect of Anti-Fractalkine Antibody (5H8-4) on Expressions of mRNAs for Cell Surface Markers, Cytokines, Chemokines, Cell Activation Molecules and Cytotoxic Molecules in Mouse Oxazolone-Induced Inflammatory Bowel Disease Model
(1) Method
An inflammatory bowel disease model was prepared in the same manner as that used in Example 2. The control antibody and the anti-fractalkine antibody (5H8-4) were administered according to the method in Example 2. Autopsy was performed 24 hours and three days after the intestinal injection of oxazolone, the large intestine was removed, and then RNA was extracted from the large intestine tissues in the same manner as that used in Example 1. The negative control group was given intestinal injection of 50% ethanol/physiological saline. Expressions of mRNAs for cytokines and chemokines were measured by TaqMan PCR in the same manner as that used in Example 1 by extracting RNA and then synthesizing cDNA. The used primer sets are as follows.









TABLE 6







SEQ ID 


Primer
Sequence
NO:







IL-1β sense
5′-GCTGAAAGCTCTCCACCTCA-3′
110


IL-1β anti-sense
5′-AGGCCACAGGTATTTTGTCG-3′
111


IL-6 sense
5′-CAAAGCCAGAGTCCTTCAGAG-3′
112


IL-6 anti-sense
5′-GCCACTCCTTCTGTGACTCC-3′
113


Ly-6G sense
5′-GATGGATTTTGCGTTGCTCT-3′
114


Ly-6G anti-sense
5′-GTCCAGAGTAGTGGGGCAGA-3′
115


KC sense
5′-CTTGAAGGTGTTGCCCTCAG-3′
116


KC anti-sense
5′-TGGGGACACCTTTTAGCATC-3′
117


MIP-2 sense
5′-TCCAGAGCTTGAGTGTGACG-3′
118


MIP-2 anti-sense
5′-GCCTTGCCTTTGTTCAGTATC-3′
119


MCP-1 sense
5′-GGTCCCTGTCATGCTTCTG-3′
120


MCP-1 anti-sense
5′-TCATTGGGATCATCTTGCTG-3′
121


MIP-1α sense
5′-ACCATGACACTCTGCAACCA-3′
122


MIP-1α anti-sense
5′-GATGAATTGGCGTGGAATCT-3′
123


MIP-1β sense
5′-CCCACTTCCTGCTGTTTCTC-3′
124


MIP-1β anti-sense
5′-CTCACTGGGGTTAGCACAGA-3′
125


MCP-3 sense
5′-CTGCTTTCAGCATCCAAGTG-3′
126


MCP-3 anti-sense
5′-CCCAGGGACACCGACTACT-3′
127


CXCR2 sense
5′-GCTCACAAACAGCGTCGTAG-3′
128


CXCR2 anti-sense
5′-AGGGCATGCCAGAGCTATAA-3′
129









(2) Results

Twenty four hours after the intestinal injection of oxazolone, increases in expressions of mRNAs for inflammatory cytokines such as IL-13 and IL-6, chemokines such as KC, MIP-2, MCP-1, MCP-3, MIP-1α and MIP-1β and chemokine receptor CXCR2 were observed in the control antibody administration group, and these expression increases were markedly inhibited by the administration of the anti-fractalkine antibody (FIG. 24). Three days after the intestinal injection of oxazolone, an increase was observed in expression of mRNA for Ly-6G, a neutrophil marker, in addition to increases in expressions of mRNA for IL-1β, IL-6, KC, MIP-2, MCP-1, MCP-3 and CXCR2, and this increase in expression was markedly inhibited by administration of the anti-fractalkine antibody (FIG. 25). These results suggested that the pathological condition improving effect of the anti-fractalkine antibody in the oxazolone-induced inflammatory bowel disease model was exhibited partly by inhibition of production of the inflammatory cytokines and chemokines such as IL-1β and IL-6 or inhibition of infiltration of neutrophils.
INDUSTRIAL APPLICABILITY
There is provided a therapeutic agent for an inflammatory disease based on a novel approach, i.e., selective inhibition of excessive NO production by inhibition of iNOS activity in inflammatory cells.

## Claims

1. A method for treating an inflammatory bowel disease, the method comprising administering a therapeutically effective amount of an anti-fractalkine antibody to a subject in need thereof, wherein said anti-fractalkine antibody binds to fractalkine and inhibits an interaction of fractalkine and CX3CR1.

2. The method according to claim 1, wherein the anti-fractalkine antibody is a monoclonal antibody.

3. The method according to claim 2, wherein the anti-fractalkine antibody is a monoclonal antibody 5H8-4 produced by a hybridoma of the accession No. FERM BP-10372 or a monoclonal antibody #126 produced by a hybridoma of the accession No. FERM BP-10371.

4. The method according to claim 1, wherein the inflammatory bowel disease is ulcerative colitis or Crohn's disease.

5. The method according to claim 2, wherein the inflammatory bowel disease is ulcerative colitis or Crohn's disease.

6. The method according to claim 3, wherein the inflammatory bowel disease is ulcerative colitis or Crohn's disease.

7. The method according to claim 1, wherein the anti-fractalkine antibody is an antibody which recognizes an epitope which is recognized by a monoclonal antibody 5H8-4 produced by hybridoma of the accession No. FERM BP-10372 or a monoclonal antibody #126 produced by a hybridoma of the accession No. FERM BP-10371.

8. The method according to claim 7, wherein the inflammatory bowel disease is ulcerative colitis or Crohn's disease.