bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymorphism of age‐related changes in interleukin (IL) production: differential changes of T helper subpopulations, synthesizing IL 2, IL3 and IL4
Authors: Kubo Masato , Cinader Bernhard
Published: March 2007

Inbred mice were examined for strain differences in age‐associated changes in the capacity to synthesize interleukin (IL), i.e. IL2, IL3 and IL4 after stimulation with phorbol myristate acetate (PMA) and calcium ionophore (A23187). Production of IL2remains constant in A/J, DBA/1 and DBA/2 mice and decreases with age in one of the strains examined (C57BL/6J). Strain differences in age‐associated changeof synthesis did not show the relation between youthful synthetic capacity and magnitude of later decrease (“economic correction”) which is observed in several other systems. This difference between different types of polymorphisms is attributed to an age‐associated defect in intrinsic capacity to synthesize IL2 which may occur in onlyone of the tested strains, C57BL/6J. In contrast to IL 2 production, the quantities of IL3 and IL4 increase progressively, with advancing age, in mice of the three strains tested. T cells from old mice contain a greater frequency of cells producing IL3, than do those of young mice. In addition, synthesis of IL3 is induced at a relatively lower concentration of PMA in cells from old animals and this may be a consequence of different signal requirements of the two subsets of the T helper cells, but also a change in intrinsic properties of these cells. Since IL3 and IL4 production, but not IL2 production, increaseswith age, it is reasonable to conclude that this reflects an expansion of a T helper cellpopulation which secretes IL3 and IL4, but not IL2, presumably TH2.
Paradoxical lessening of autoimmune processes in non‐obese diabetic mice afterinfection with the diabetogenic variant of encephalomyocarditis virus
Authors: Hermitte Laurence , Vialettes Bernard , Naquet Philippe , Atlan Catherine , Payan Marie‐josé , Vague Philippe
Published: March 2007

In order to gain insight into the interaction between autoimmunity and viral infection in the onset of insulin‐dependent diabetes, non‐obese diabetic (NOD) micewhich spontaneously develop autoimmune diabetes were inoculated with the diabetogenic variant of the encephalomyocarditis virus (EMCV‐D) before the onset of the disease. The pre‐diabetic period was divided into two phases: the early phase (days 88 to 116) during which development of spontaneous diabetes is rare and the late phase (day 123 to 200) during which the incidence of spontaneous diabetes is high. As controls ICR mice of common ancestry were also inoculated. During the early phase diabetes was observed in 4/10 inoculated, 0/13 control NOD and 7/13 inoculated ICR males vs. 6/12 inoculated, 1/11 control NOD and 0/15 inoculated ICR females. However, in NOD female, virus‐induced diabetes prevalence was variable from one experiment to another. In parallel the flow cytometric analysis showed a high percentage of L3T4+ T lymphocytes in the pancreas of inoculated female NOD mice 10 days after the infection. At this time a large proportion of both L3T4+ and Ly‐2+ cells expressed the interleukin 2 receptor. During the late phase no new case of diabetes occurred in inoculated NOD mice but one case was observed in control NOD males and five in control NOD females. This prevention of autoimmune diabetes was constantly found in other experiments. Insulitis was milder in inoculated NOD mice of both sexes than in control NOD. Adoptive transfer of diabetes into irradiated 8‐week‐old males by splenocytes from 28‐week‐old females was successful in five out seven attempts with control splenocytes and in zero out of six attempts with splenocytes from inoculated mice. This immunosuppression was specific as the ability of lymphocytes to respond to soluble or allogeneic antigens was preserved.

In the early phase EMCV‐D precipitated the onset of diabetes in females NOD mice by amplifying L3T4+ T lymphocyte‐mediated immune mechanisms. During the late phase viral infection had lessened immune processes in animals which had resistedor recovered from virus‐induced diabetes.
Major histocompatibility complex regulation of the class of the immune response: the H‐2d haplotype determines poor interferon‐γ response to several antigens
Authors: Asherson Geoffrey L. , Dieli Francesco , Gautam Yvonne , Khai Siew L. , Zembala Marck
Published: March 2007

The lymph node cells of CBA (H‐2k), but not BALB/c (H‐2d) mice, release interferon (IFN)‐γ into the supernatant when immunized with picryl chloride epicutaneously and then exposed to antigen (haptenized cells) in vitro 4 days later. The failure in IFN‐γ production maps to the major histocompatibility complex (MHC; H‐2d) in the congenic BALB/c, BALB/k and BALB/b mice. The evidence that this is an MHC regulation of the class of response to a range of antigens and not a classical Ir gene effect is (a) the difference is seen with several antigens including picryl chloride, “oxazolone” and purified protein derivative of tuberculin and (b) BALB/c mice, which fail to produce IFN‐γ, show excellent contact sensitivity to picryl chloride. It was also found that the crosses between responder and nonresponder strains (CBA × BALB/c)F1 respond to antigen on responder cell but not on nonresponder cells. This influence ofMHC on the class of the immune response is a possible basis for some of the associations of MHC with disease.
Partial tolerance in β‐galactosidase‐transgenic mice
Authors: Theopold Ulrich , Köhler Georges
Published: March 2007

A transgenic mouse line was produced which allowed the expression of E. coli β‐galactosidase (β‐Gal) under the regulatory elements of the immunoglobulin heavy chain locus. Expression of the transgene is found in spleen and bone marrow. Upon immunization of the transgenic mice with β‐Gal, a reduced but clearly detectable antibody response was obtained. Affinity purification with sera from immunized transgenic mice suggests that they contain lower affinity antibodies as compared to normal littermates.

Transgenic and nontransgenic mice immunized with bovine serum albumin (BSA) alone or as amixture with β‐Gal gave comparable anti‐BSA responses. Immunization with a chemically cross‐linked (Gal‐BSA)‐protein, however, showed a 10‐ to 30‐fold difference in the anti‐BSA response. Partial unresponsiveness to β‐Gal in the transgenic mice is best explained by a dominant, peripheral suppression mechanism linked to the antigen‐presenting potential of B cells.
Distribution, inducibility and biological function of the cloned and expressed human βFc receptor II
Authors: Engelhardt Waltraud , Geerds Christina , Frey Jürgen
Published: March 2007

A cDNA encoding the human βFcγ receptor II (FcRII) was isolated from a placental cDNA library. Analysis of the predicted amino acid sequence indicates that this receptor is synthesized with a 42‐amino acid leader sequence. The mature protein consists of 249 amino acids. The leader sequence and the cytoplasmic domain are strikingly different from the CDw32 antigen but show great homology to the mouse β2FcR. RNA blot analysis of human cells using CDw32 and βFcRII‐specific DNA fragments demonstrated one βFcRII transcript (1.7 kb) in B cells and in HL‐60 cells which were induced to differentiate along a monocyte‐macrophage pathway by phorbol 12‐myristate 13‐acetate treatment. Under these conditions the CDw32 transcripts (2.5 and 1.7 kb) are induced to a minor extent in HL‐60 cells. In contrast, the 2.5‐kb CDw32 transcript is strongly induced in HL‐60 cells which have been induced to differentiate into granulocytes by exposure to dimethylsulfoxide. To determine the biological properties of the βFcRII, we expressed the antigen in FcR− hamster cells. Only immune complexes but not monomeric human IgG were bound significantly. Bound ligand was efficiently internalized within 15 min and it was then found in vesicular structures. Thus the low‐affinity βFcRII is able to internalize ligands without cooperation with any other FcR.
Mast cell growth‐enhancing activity (MEA) is structurally related and functionally identical to the novel mouse T cell growth factor P40/TCGFIII (interleukin 9)
Authors: Hültner Lothar , Druez Catherine , Moeller Jochen , Uyttenhove Catherine , Schmitt Edgar , Rüde Erwin , Dörmer Peter , van Snick Jacques
Published: March 2007

We have previously shown that certain bone marrow‐derived mast cell (BMMC) lines proliferate in response to a mast cell growth‐enhancing activity (MEA) that is distinct from interleukin (IL) 3 and IL 4. Here we provide evidence that MEA is identical with the recently cloned mouse T cell growth factor P40. The evidence is as follows: (a) recombinant P40 displayed all the biological activities ascribed to MEA: it supported the growth of MEA‐sensitive BMMC lines, it induced IL 6 secretion by these cells, and it enhanced survival of primary mast cell cultures; (b) highly purified MEA stimulated the growth of P40‐dependent cell lines; (c) a rabbit monospecific antiserum directed against P40 specifically inhibited the action of MEA on BMMC; (d) specific binding sites for P40 were detected on BMMC and (e) MEA competed with P40 for binding to P40‐dependent T cells, indicating that the two molecules interact with the same receptor. These observations further extend the range of biological activities ascribed to P40 and warrant its proposed designation as IL 9.
Recognition of a particular HLA‐DQ heterodimer by a human γ/δ T cell clone
Authors: Bosnes Vidar , Qvigstad Erik , Lundin Knut E. A. , Thorsby Erik
Published: March 2007

Peripheral blood mononuclear cells from a single donor were depleted of T cell receptor (TcR) α/β T cells, stimulated with allogeneic cells, and γ/δ T lymphocyte clones (TLC) were isolated by limiting dilution. Five TLC were cytotoxic against B‐lymphoblastoid cell lines from the stimulating cell donor, and demonstrated a restricted allospecificity in panel cell studies. One of these, γ/δ TLC RNG‐135, was studied in more detail. Its phenotype was CD3+ TcR α/β− TcR γ/δ+ BB3− δTCS1+ CD4− CD8−. Inhibition experiments using monoclonal antibodies indicated that the cytotoxicity of TLC RNG‐135 was mediated through the TcR γ/δ, and directed against an HLA‐DQ molecule. In extended panel cell experiments, this γ/δ TLC only lysed cells carrying the DQA1*0501 and DQB1*0301 genes, either in cis position (on the DR5, DQw7 haplotype), or in trans position (the donor of the stimulating cells, DR3,4; DQw2, w7). Thus, it appears that γ/δ T cells may recognize a particular HLA‐DQ α/β heterodimer, which may be encoded by DQA1 and B1 genes both in cis and trans position.
Reevaluation of the C3a active site using short synthetic C3a analogues
Authors: Köhl Jörg , Casaretto Monika , Gier Martina , Karwath Gabriele , Gietz Claudia , Bautsch Wilfried , Saunders Derek , Bitter‐Suermann Dieter
Published: March 2007

In 1980 the C‐terminal pentapeptide LGLAR (C3a 73–77) was described (Caporale, L. H. et al. J. Biol. Chem. 1980. 255: 10758) as the minimal sequence inducing a C3a‐specific activity. We have synthesized C3a‐analogue peptides connected to non‐peptidic acyl residues known to potentiate biological activity. Starting from the acylated hexapeptide fluorenylmethoxycarbonyl(Fmoc)‐aminohexanoyl(Ahx)‐ALGLAR, a related series of shorter peptides was synthesized. C3a‐specific activity was measured as ATP release from guinea pig platelets. Even the tripeptide LAR, acylated with Fmoc‐Ahx, exhibited C3a‐specific activity. With 0.34% C3a activity, it was even more potent than the native LGLAR sequence which has 0.01% activity. N‐terminal extension of the acylated tripeptide LAR by adding one to three alanines increased activity tenfold up to 3.26% (Fmoc‐Ahx‐AAALAR), while N‐terminal addition of three glycine residues (Fmoc‐Ahx‐GGGLAR) only increased activity to 0.83% of native C3a. Furthermore, a stimulus‐specific desensitization could be observed. Fmoc‐Ahx‐R and Fmoc‐Ahx‐AR exhibited neither activity nor desensitizing capacity, but the addition of four alanines to the dipeptide AR led to a sequence (Fmoc‐Ahx‐AAAAAR) with a C3a‐specific activity of 0.14%. Even arginine prolonged N‐terminally with five glycines (Fmoc‐Ahx‐GGGGGR) exhibited some C3a‐specific activity so that for biological activity only the appropriate presentation of arginine seems to be essential.
Isolation of high‐affinity murine interleukin 2 receptors as detergent‐resistant membrane complexes
Authors: Hoessli Daniel C. , Poincelet Monique , Rungger‐Brändle Elisabeth
Published: March 2007

Murine T cells and T cell lines bearing high‐ and low‐affinity receptors for interleukin (IL) 2 were chemically cross‐linked to radiolabeled IL 2 and subjected to differential detergent extractions to evaluate the extent of IL 2 receptor association with the nonionic detergent‐resistant framework of the plasma membrane. Low‐affinity receptors were readily solubilized by nonionic detergent extraction of whole cross‐linked cells, while solubilization of high‐affinity receptors required a stronger ionic detergent suggesting their association with a membrane structure that is resistant to nonionic detergents.

To achieve physical separation of low‐ and high‐affinity receptors, cells cross‐linked to 125I‐labeled IL 2 were centrifuged through a sucrose barrier containing Triton X‐100. Alternatively, Triton X‐114 extracts of plasma membrane fractions were partitioned into aqueous and detergent phases. By either approach, high‐affinity receptors differed from low‐affinity ones by their increased density and consisted of detergent‐resistant complexes containing p55‐p75 heterodimers. The low‐affinity receptors, on the contrary, were of low density and consisted exclusively of detergent‐soluble p55 subunits. High density and resistance to nonionic detergent extraction of high‐affinity IL 2 receptors suggest their integration into lateral microdomains of the detergent‐resistant framework of the plasma membrane.
Ontogeny of the humoral response to group A streptococcal carbohydrate: Class and IgG subclass composition of antibodies in children
Authors: Morell Andreas , Doran Jan E. , Skvaril Frantisek
Published: March 2007

We determined isotypes of natural antibodies to streptococcal group A carbohydrate (A‐CHO) in sera from 101 children between 1 and 16 years of age, using a calibrated enzyme‐linked immunosorbent assay system. Anti‐A‐CHO IgM could be detected in all but one sera. Median levels increased with age and were highest between 8 and 12 years. IgG antibodies were present at low concentrations up to the age of 4 years, and consisted predominantly of the IgG1 subclass. Between 4 and 8 years, concentrations of anti‐A‐CHO IgG markedly increased and median levels continued to increase through age 12–16. Anti‐A‐CHO IgG1 levels closely followed the pattern of IgG antibody concentrations. The number of IgG2 antibody positive sera was low in young children, as expected. In the 8–12 year age group and later, anti‐A‐CHO IgG2 was present in more than half of the samples, and in children between 12 and 16, medians of IgG2 and IgG1 antibodies were similar. Sera containing anti‐A‐CHO IgG3 were rare in children up to 4 years of age, but in the group of 4–8‐year‐old children, this subclass was detectable in 36% and later in up to 77% of the sera. Thus, the IgG response to A‐CHO showed a clear maturation during childhood, involving the subclasses IgG1, IgG2 and IgG3. There were no significant differences in A‐CHO levels between boys and girls.
Involvement of major histocompatibility complex class I antigens in T cell activation
Authors: Dasgupta Jai Dev , Egea Eduardo , Relias Valerie , Iglesias Antonio , Gladstone Paul , Yunis Edmond J.
Published: March 2007

During the last few years ample evidence has been collected indicating a regulatory role for major histocompatibility complex class I antigens (Ag) in T cell activation. However, due to differential effects (stimulatory and inhibitory) of anti‐class I antibodies (Ab) observed under different conditions, no coherent scheme of the mechanism of action of these Ag has emerged. Here, we present evidence that the mode of action of anti‐class I Ab depends upon the presence or absence of monocytes/macrophages (MΦ) in the culture. The Ab inhibit Ag presentation by binding to MΦ. Coating of tetanus toxin ‐pulsed MΦ with anti‐class I Ab is sufficient to suppress T cell activation. On the contrary, these Ab enhance lectin‐ as well as phorbol ester‐induced T cell activation in the absence of MΦ. Cross‐linking of class I Ag on T cell surface mobilizes cytoplasmic Ca2+, and also enhances the CD3‐induced Ca2+ flux inside the cells indicating a functional relationship between CD3 and class I Ag. Though surface modulation and immunoprecipitation experiments do not indicate any physical association between these two types of molecules on the T cell surface, capping studies show that cross‐linking of class I Ag induces an association of these Ag with CD3. Binding of anti‐CD3 Ab enhances the strength of association between CD3 and class I Ag, and the former co‐caps completely with the latter. Based on these observations we propose that during antigen presentation MΦ (or Ag‐presenting cells) and T cells, besides interacting via peptide–class II Ag/CD3–T cell receptor complex formation, also interact through class I Ag. The latter interaction may stabilize the contact formation between T cells and Ag‐presenting cell and support T cell activation.
All VH11 genes expressed in peritoneal lymphocytes encode anti‐bromelain‐treated mouse red blood cell autoantibodies but other VH gene families contribute to this specificity
Authors: Poncet Pascal , Huetz François , Marcos Miguel‐Angel , Andrade Luiz
Published: March 2007

We have studied the relationship between B cell reactivity to bromelain‐treated autologous mouse erythrocytes (BrMRBC) and expression of the VH11 gene family in splenic, peritoneal and pleuropericardial cell populations from normal C57BL/6 mice. B lymphocytes producing antibodies to BrMRBC were selectively enriched or depleted from normal populations by rosette formation with BrMRBC, followed by centrifugation over density gradients. This selection method, based on the presence of functional receptors (membrane IgM), is harmless for the cells and allowed subsequent cloning in agar (colony‐forming unit‐B). The utilization of the 10 VH gene families was then scored in mRNA colony blot assays. The analysis of > 650 anti‐BrMRBC clones and > 350 VH11‐expressing colonies indicates that about half of those antibody reactivities are encoded by VH11 genes. Furthermore, it appears that all VH11‐expressing B cells in the peritoneal cavity produce anti‐BrMRBC antibodies.
Characterization of the murine heat‐stable antigen: An hematolymphoid differentiation antigen defined by the J11d, M1/69 and B2A2 antibodies
Authors: Alterman Lesley A. , Crispe I. Nicholas , Kinnon Christine
Published: March 2007

The heat‐stable antigen (HSA) is a marker of hematopoietic differentiation in both the B and T cell lineages. The antigen is recognized by a series of monoclonal antibodies which includes J11d, M1/69 and B2A2, and in addition YBM 5.10.4. We show here that all these antibodies recognize the same antigenic determinant which is expressed on a variably glycosylated membrane protein. Tunicamycin experiments show that the antigen is not carbohydrate in nature as it is expressed on two unglycosylated protein core molecules of molecular mass ca. 20 kDa and 17 kDa. Furthermore, the antigenic determinant appears to be lost following phosphatidylinositol‐specific phospholipase C cleavage. Although the molecular mass of HSA appears to be heterogenous on cells of different lineages, these variations in size appear to be due primarily to differences in the extent of N‐linked glycosylation, since both protein core molecules were found in all cell types investigated which express the antigen. These findings have important implications for the structure and function of this antigen and its role in hematopoietic development.
Association of a particular amino acid sequence of the HLA‐DR β1 chain with HTLV‐I‐associated myelopathy
Authors: Usuku Koichiro , Nishizawa Masatoyo , Matsuki Kazumasa , Tokunaga Katsushi , Takahashi Keikichi , Eiraku Nobutaka , Suehara Masahito , Juji Takeo , Osame Mitsuhiro , Tabira Takeshi
Published: March 2007

Analyses of HLA‐DRB1 gene using polymerase chain reaction and sequence‐specific oligonucleotide probes reveal that the amino acid sequence Glu‐Gln‐Arg‐Arg‐Ala‐Ala‐Val at positions 69–75 of the third hypervariable region (HVR) of HLA‐DR β1 chain is significantly associated with HTLV‐I‐associated myelopathy (HAM). Since the frequency of this sequence in HTLV‐I carriers is almost the same as that in controls from Kagoshima (an endemic area of HTLV‐I), this sequence may be related to susceptibility to HAM rather than to susceptibility to HTLV‐I infection. Since this third HVR functions as putative antigen‐binding sites and T cell recognition sites, the amino acid sequence of positions 68–73 was analyzed in detail. The analysis reveals that Gln70 and Arg71 are relevant to the occurrence of HAM.
A multiple antigen peptide from the repetitive sequence of the Plasmodium malariae circumsporozoite protein induces a specific antibody response in mice of various H‐2 haplotypes
Authors: Del Giudice Giuseppe , Tougne Chantal , Louis Jacques A. , Lambert Paul‐Henri , Bianchi Elisabetta , Bonelli Fabio , Chiappinelli Lorella , Pessi Antonello
Published: March 2007

The major repetitive epitopes of the surface circumsporozoite (CS) protein of malaria sporozoites represent candidates for the development of subunit vaccines against malaria. However, previous experimental work has shown that repetitive peptides from the CS proteins of Plasmodium falciparum, P. vivax, P. yoelii and P. berghei are immunogenic only in mice with the H‐2b or H‐2k haplotype. This led to the conclusion that strong T helper epitopes from the non‐repetitive CS sequences were required in the design of sporozoite vaccines. In the present study, we investigated the immunogenicity in mice of a octa‐branched multiple antigen peptide (MAP) containing repeats of the CS protein of the human malaria parasite, P. malariae, [MAP8(NAAG)6], and found that mice with an H‐2b, H‐2d, H‐2k, H‐2f, H‐2q, and H‐2s haplotype produced anti‐peptide antibodies after immunization and that only H‐2r mice were nonresponsive. This antibody response, not induced in athymic H‐2b nulnu mice, was directed against the (NAAG) sequence, but not against the lysine core of the MAP construct. Finally, when covalently linked to a synthetic polymer of the repetitive (NANP) sequence of the P. falciparum CS protein, [MAPs(NAAG)6] behaved as a carrier molecule for the production of anti‐(NANP)n antibodies in H‐2d and H‐2k mice, genetically nonresponder to the (NANP)n sequence. Should this wide immunogenicity of the P. malariae CS (NAAG) repetitive sequence also apply to humans, it might be considered for the design of multivalent subunit malaria vaccines.
Anti‐immunoglobulin antibodies induce apoptosis in immature B cell lymphomas
Authors: Hasbold Jhagvaral , Klaus Gerry G. B.
Published: March 2007

WEHI‐231 and CH31 are phenotypically immature sIgM+ murine B cell lymphomas whose growth is inhibited by anti‐immunoglobulin (Ig) antibodies. These lines have therefore been used as models for studying the role of surface Ig receptors in the induction of B cell tolerance. We show here that anti‐γ antibodies induce DNA cleavage into oligonucleosomal fragments characteristic of programed cell death (apoptosis) in both cell lines, although WEHI‐231 cells are less susceptible than CH31. This effect was reversed by lipopolysaccharide, in agreement with the known effects of lipopolysaccharide on anti‐Ig‐induced growth inhibition. These results therefore indicate that these lymphomas afford a potentially interesting model to study the mechanisms of programed cell death induced by ligation of the antigen receptors on normal B cells.
Accumulation of bromodeoxyuridine‐labeled cells in central and peripheral lymphoid organs: minimal estimates of prodution and turnover rates of mature lymphocytes
Authors: Rocha Benedita , Penit Claude , Baron Christophe , Vasseur Florence , Dautigny Nicole , Freitas Antonio A.
Published: March 2007

Daily lymphocyte prodution in both central and peripheral lymphoid organs was evaluated by associating in vivo incorporation of bromodeoxyuridine (BrdUrd) with cell surface labeling and multi‐parameter flow analysis. At least 10% of mature T and B lymphocytes are generated every 24 h. The kinetic behavior of these cell populations differs, however, in that mature B cells are generated predominantly in the precursor compartments of the bone marrow, while most mature T cell generation occurs at the periphery. Therefore, peripheral expansion is the major mechanism of mature T cell production in the adult mouse. By following the accumulation of BrdUrd‐labeled cells in peripheral lymphoid organs we found that the progeny of the daily lymphocyte production was sufficient to renew 30%‐40% of all peripheral T and B cells every 48 h, demonstrating a high turnover rate of mature lymphocytes.

We also examined the conditions of BrdUrd labeling of cycling cells in vivo. We found that while > 90% of bone marrow and thymus cells in S phase were labeled with a single injection of BrdUrd, in peripheral lymphoid compartements 70% of T and B cells in S failed to incorporate BrdUrd. Particular schedules of BrdUrd administration were required to overcome the low labeling efficiency of mature cells in vivo. Prolonged BrdUrd administration, however, had toxic effects on resident cells. The low labeling efficiency of BrdUrd incorporation by mature cells, as well as its potential toxicity during prolonged administration, may explain controversial results obtained by the different strategies used to study lymphocyte population dynamics.
Establishment of different T cell sublines using either interleukin 2 or interleukin 4 as growth factors
Authors: Schmitt Edgar , Van Brandwijk Renate , Fischer Hans‐Georg , Rüde Erwin
Published: March 2007

Purified protein derivative reactive T cell lines were established under identical conditions with the exception that different lymphokines, namely interleukin (IL) 2 and IL 4 were employed as growth factors. IL 2 favored the development of T cell lines (LNC.2) which upon activation by concanavalin A (Con A) secreted predominantly lymphokines characteristic of TH1 cells. By contrast, T cell lines established with the aid of IL4 as growth factor (LNC.4) produced mainly lymphokines representative of TH2 cells. Apart from their pattern of lymphokine secretion LNC.2 and LNC.4 T cells were found to differ in their proliferative response to lymphokines and Con A. LNC.2 T cells proliferated only marginally in the presence of IL 4, Con A or a combination of Con A and IL 1. Furthermore, the IL 2‐dependent proliferation of LNC.2 T cells was slightly but significantly diminished by IL 4. In contrast, LNC.4 T cells showed a substantial IL 4‐induced proliferative response which was on the one hand synergistically enhanced by minimal amounts of IL 2 and, on the other hand, strongly inhibited by interferon‐γ. In addition, LNC.4 T cells displayed a strong proliferation when stimulated by low concentrations of Con A in the presence of IL 1 as co‐stimulator.
Differential expression of interleukin 1α by Thy‐1+ and Thy‐1− lung fibroblast subpopulations: Enhancement of interleukin 1α production by tumor necrosis factor‐α
Authors: Phipps Richard P. , Baecher Clare , Frelinger John G. , Penney David P. , Keng Peter , Brown Deborah
Published: March 2007

The purpose of this investigation was to determine whether subpopulations of murine lung fibroblasts produced interleukin 1 (IL 1). We previously identified two major populations of pulmonary fibroblasts based on the presence or absence of Thy‐1. Thy‐1+ and Thy‐1− subsets synsthesize fibronectin and type I and III collagen, but only the Thy‐1− population displays class II major histocompatibility complex antigens after stimulation with interferon‐γ and presents antigen to T helper clones. Interestingly, in the current study we determined that only Thy‐1− fibroblast lines and clones synthesized IL 1. Although constitutive production was low, tumor necrosis factor ‐α (TNF‐α) stimulated 5‐20‐fold increases in IL 1 production in Thy‐1− fibroblasts. The Thy‐1+ fibroblasts did not produce IL 1 even after TNF‐α treatment. Northern blot analysis of TNF‐α treated cells revealed that in the Thy‐1− subset increased mRNA levels for IL 1α were detected, while IL 1β mRNA was not detected. Furthermore, IL 1 activity from TNF‐α‐treated Thy‐1− fibroblast membranes and supernatants was completely neutralized by IL 1α‐specific antibodies. These observations support the hypothesis that the antigen‐presenting Thy‐1− subset is important for promoting the inflammation associated with pulmonary fibrosis. In addition, the existence of functional subsets of lung fibroblasts is further substantiated by differential expression of IL 1.
Ontogenic characterization of thymic B lymphocytes. Analysis in different mouse strains
Authors: Andreu‐Sánchez Jose L. , Faro Jose , Alonso Jose M. , Paige Christopher J. , Martínez‐A. Carlos , Marcos Miguel A. R.
Published: March 2007

We have characterized a population of murine B lymphocytes present in the thymus (TBL). They are a minor subset (0.2%−1% of total thymocytes), present from perinatal periods onwards and constituted by activated cells with a high proportion of Ig‐secreting cells. They represent the first B lymphocytes detected that secrete IgG after birth. Functional analysis reveals that the frequency of lipopolysaccharide‐responding cells in TBL is 5‐ to 10‐fold lower than in the spleen. TBL from adult mice did not show any significant difference in their VH repertoire expression when compared to peripheral B lymphocytes. Further‐ more, we have been able to isolate a subpopulation of B220+IgM−CD3− thymocytes whose putative B cell precursor potential needs to be directly analyzed. These and other findings support the intrathymic resident characteristics of TBL and suggest new ways of elucidating its physiological role in the complex selective processes occurring inside the thymus.
Failure to find alloimmune memory in the resorption phenomenon of Botryllus cytomictical chimera
Authors: Rinkevich Baruch , Weissman Irving L.
Published: March 2007

It has been previously shown that mixed‐cell chimeras may be established between different colonies of the compound tunicate Botryllus schlosseri given that they share one allele in common on the fusibility locus. However, one of the partners in each chimera is often resorbed. Here we tested for the existence of a memory component to this response, as measured by the accelerated interval to resorption of a second set of semiallogeneic colonies. Eight genetically unrelated colonies gave rise to eighteen chimeras. After a complete resorption of the “inferior” partners in these chimeras, secondary and tertiary sets of chimeras were established with some of them by fusion of the “superior” with naive subclones of the “inferior” partners. It is shown here that (a) when multiple chimeras are prepared using the same pair of colonies, subclones of only one of the partners are resorbed; (b) high variation in the time for resorption is recorded when several chimeras are prepared from any specific pair of colonies, and (c) the time for resorption is not related to the number of vessels connecting between the partners in the chimera, nor to their relative body sizes. Allospecific memory is not documented here and reasons for its absence are discussed.
Human CD8+ intraepithelial T lymphocytes are mainly CD45RA−RB+ and show increased co‐expression of CD45R0 in celiac disease
Authors: Halstensen Trond S. , Scott Helge , Brandtzaeg Per
Published: March 2007

Expression of various CD45 isoforms (RA, RB and R0) on CD3+, CD4+ and CD8+ intraepithelial and lamina propria T cells was examined in situ by a three‐color immunofluorescence technique in jejunal biopsy specimens from 32 patients with celiac disease and 18 controls. The median percentage of CD3+ intraepithelial lymphocytes (IEL) that expressed CD45R0 increased from 52% in controls to 69% in untreated celiac disease (p < 0.01). Furthermore, the percentages of CD4+ and CD8+ IEL strongly positive for CD45R0 rose respectively from 94% and 24% in controls to 100% and 55% in untreated celiac disease. Conversely, CD45R0 was strongy expressed on most CD3+ lamina propria lymphocytes (LPL) both in control (81%) and diseased (77%–81%) mucosa. A variable fraction of the intraepithelial and lamina propria CD3+ T cells expressed mainly CD45RB (controls, 46% and 20%, respectively; celiac disease, 29% and 15%). Only 2% IEL and 4% LPL were positive for CD45RA. Expression of different CD45R isoforms thus identified three distinct CD8+ T cell subsets in human intestinal mucosa. In addition, our results suggested that antigen‐primed CD8+CD45R0+ memory cells accumulate in the jejunal epithelium of patients with untreated celiac disease.
Activation of human B lymphocytes by nanogram concentrations of anti‐IgM‐dextran conjugates
Authors: Rehe Gregory T. , Katona Ildy M. , Brunswick Mark , Wahl Larry M. , June Carl H. , Mond James J.
Published: March 2007

Surface immunoglobulin (sIg) cross‐linking on B lymphocytes by high concentrations of anti‐Ig antibody has been used to mimic antigen‐stimulated B cell activation. In order to develop a system to study sIg‐mediated Tcell‐independent B cell activation using low concentrations of anti‐Ig antibody that more closely resemble the concentrations of antigen that are achieved under in vivo conditions, we conjugated monoclonal anti‐human IgM antibody (anti‐μ) to dextran (molecular weight 2 × 106) thereby increasing its valency. This dextran conjugate (anti‐μ‐Dex) stimulated comparable levels of thymidine incorporation and B cell size increases as were seen with unconjugated anti‐μ but at 100‐ to 1000‐fold lower concentrations. Anti‐μ‐Dex also stimulated increases in intracellular ionized calcium ([Ca2+]i) in a higher percentage of cells, of greater magnitude and of longer duration than that stimulated by unconjugated anti‐μ. Interestingly, there was no direct correlation between the increases in [Ca2+]i that were stimulated by anti‐μ‐Dex and its ability to stimulate B cell proliferation. The concentrations of anti‐μ‐Dex (10 μg/ml) that led to the highest increase in [Ca2+]i resulted in thymidine incorporation that was no greater than that of medium control, whereas 0.01 to 0.1 μg/ml stimulated significant thymidine incorporation with 50% lower levels of stimulation of [Ca2+]i. These data demonstrate that anti‐μ‐Dex is a potent activator of human B lymphocytes, is effective even at ng/ml concentrations which over a 2‐h time period do not induce detectable modulation of sIg, and its stimulation of B cells into G1 and S may not be directly related to its ability to stimulate increases in levels of [Ca2+]i.
Abnormal behavior of γ‐committed B lymphocytes probed by a lymphocyte blastogenesis inhibitory factor in autoimmune MRL mice
Authors: Sugimura Kazuhisa , Wada Yumiko , Kimura Tatsuji , Ohno Takeshi , Kobayashi Seiichi , Azuma Ichiro
Published: March 2007

Recently, we have characterized a lymphocyte blastogenesis inhibitory factor (LBIF) which was purified from the culture supernatant of a human histiocytic lymphoma U‐937 (Sugimura, K. et al., Eur. J. Immunol. 1989. 19: 1357). In this study, we investigated the effect of LBIF on the antibody production of autoimmune MRL mice in vitro. We demonstrated here that (a) LBIF inhibited the IgM, IgG and IgA antibody responses of lipopolysaccharide (LPS)‐stimulated spleen cells of normal BALB/c mice, (b) in the case of old autoimmune MRL/Mp‐lpr/lpr (MRL/l) and MRL/Mp‐+/+ mice, however, LBIF inhibited IgM and IgA but not IgG responses of LPS‐stimulated spleen cells, (c) the antibody production of all IgG subclasses, IgG3, IgG1, IgG2b and IgG2a, was not sensitive to LBIF inhibitory activity in these autoimmune mice, (d) in young MRL mice (3–5‐week‐old MRL/l), which were phenotypically normal, LPS‐induced antibody production of all isotypes (IgM, IgG and IgA) was strongly inhibited by LBIF as shown in normal BALB/c mice and (e) in the case of 7‐week‐old MRL/l the insensitivity to LBIF was concomitant with the appearance of γ+ B lymphocytes.

Thus, by employing LBIF as a probe, this study showed a correlation between the pathogenesis of MRL autoimmune disease and the lack of LBIF sensitivity of hyperactive B lymphocytes and suggested that the intrinsic abnormality of autoimmune MRL B lymphocytes might be confined to γ‐ but not μ‐ or α‐committed B cells.
Immunochemical characterization of antigenic domains on human interferon‐β: spatially distinct epitopes are associated with both antiviral and antiproliferative activities
Authors: Redlich Philip N. , Grossberg Sidney E.
Published: March 2007

The use of a panel of monoclonal antibodies (mAb) raised against recombinant (serine‐17) human interferon‐β (rHuIFN‐βser) has permitted the identification of three epitopes on HuIFN‐β, designated as sites I, II and III, based solely on functional differences, i.e., the neutralization of antiviral and antiproliferative activities of natural and recombinant HuIFN‐β (Redlich, P. N. and Grossberg, S. E., J. Immunol. 1989. 143: 1887). Site I‐ and II‐directed mAb possessed neutralizing activity whereas none was noted by mAb recognizing site III. To characterize further these epitopes by immunochemical means, we studied their (a) spatial relationship by competitive binding assays, (b) antigenic structure by Western blotting, and (c) sensitivity to chemical modification by the measurement of mAb reactivity after radioiodination. Competitive antibody binding studies revealed site II to be spatially distinct from sites I and III. Furthermore, site I‐ and II‐directed mAb could easily recognize rHuIFN‐βser on a Western blot, suggesting that both these epitopes are primarily sequential in structure or denaturation resistant. Chemical modification by radioiodination, which did not alter the biologic activity of rHuIFN‐βser, had likewise little effect on mAb reactivity to site I; however, reactivity to site II was diminished and reactivity to site III was minimal following the radioiodination process. Both site I‐ and II‐directed mAb inhibited the binding of 125I‐rHuIFN‐βser to intact Daudi cells, suggesting that inhibition of receptor binding is their mechanism of neutralization. Thus, we conclude that epitopes I and II, which are associated with both antiviral and antiproliferative activities of rHuIFN‐β, are spatially and immunochemically distinct.
Inverse relationship of CA2+ mobilization and cell proliferation in CD8+ memory and virgin T cells
Authors: Schlunck Tilman , Schraut Winfried , Riethmüller Gert , Ziegler‐Heitbrock H. W. Löms
Published: March 2007

Memory T cells can now be defined with various monoclonal antibodies but little is known about the functional properties of these cells as compared to virgin T cells. We have studied Ca2+ mobilization and proliferation of memory and virgin cells in both the CD4 and CD8 subsets in response to phytohemagglutinin.

Using two‐color fluorescence (yellow, red) for cell surface staining combined with two‐color fluorescence for the Ca2+ chelator indo‐1 (violet, blue) we can demonstrate that CD8+UCHL1+ memory cells exhibit a 1,5‐fold higher influx than the CD8+UCHL1− virgin cells. The same pattern was obtained when CD8 memory and virgin cells were defined by a reciprocal marker (Leu‐18) indicating that the higher response of memory CD8 cells is independent of the monoclonal antibody used to identify the cells. For the respective CD4 subsets no such clear‐cut pattern of Ca2+ influx was evident.

Analysis of proliferation in both subsets indicates that CD8+UCHL1− cells strongly proliferate in response to PHA, while CD8+UCHL1+ memory cells show only a minimal response with the average cpm values being 6‐fold lower. In some instances no proliferation at all was detectable in the CD8+UCHL1+ cells. Identification of the subsets by reciprocal markers confirmed the lower proliferative response in the CD8 memory cells. Hence, within the CD8 compartment the memory cells, after phytohemagglutinin stimulation, exhibit a high Ca2+ mobilization but a low to absent proliferation, while the converse is true for the naive cells. These data show that (a) Ca2+ mobilization and proliferation are inversely correlated and (b) an initially vigorous response of memory cells may be subject to negative control mechanisms.
Expression of T cell receptor Vγ5 in the adult thymus of irradiated mice after transplantation with fetal liver cells
Authors: Ogimoto Masaro , Yoshikai Yasunobu , Matsuzaki Goro , Matsumoto Koji , Kishihara Kenji , Nomoto Kikuo
Published: March 2007

T cell receptor (TcR) γ/δ displays limited diversity and its diversity is distinct in different stages of ontogeny and in different anatomical sites. The Vγ5 and Vδ1 gene products are preferentially expressed on the early fetal thymocytes and on Thy‐1+ dendritic epidermal cells, whereas the Vγ4 and Vδ5 gene products are abundantly expressed on the adult thymocytes. To elucidate whether the developmentally ordered appearance of thymocytes expressing TcR γ/δ is dependent on the source of T cell precursors or is controlled by the thymic environment where T cells develop, we compared the expression of Vγ5 on the early‐appearing thymocytes between irradiated mice after transplantation with fetal liver (FL) cells and those after transplantation with bone marrow (BM) cells. Sequential appearance of thymocyte subpopulations was observed in the thymus of radiation FL chimeras similar to that seen in radiation BM chimeras. A substantial number of thymocytes bearing Vγ5 appeared in the thymus at the early stage of radiation FL chimeras, whereas few, if any, of such Vγ5‐bearing thymocytes were detected in the thymus at any stage of radiation BM chimeras. These results suggested that the ordered expression of Vγ repertoire may depend on the origin of the T cell precursors but not on the thymic environment.
Role of interleukin 2 receptor β chain in initiating anti‐CD3 and interleukin 2‐induced proliferation of human resting T cells
Authors: Moiré Nathalie , Calvo Charles‐Félix , Métivier Didier , Perrot Jean‐Yves , Vaquero Catherine , Hatakeyama Masanori , Senik Anna
Published: March 2007

We have examined the role of isolated interleukin 2 receptor (IL 2R) β chains expressed by human resting T cells in the early period of primary T cell activation induced by soluble OKT3 monoclonal antibody (mAb) and exogenous IL 2. In the initial 3‐day‐stimulation phase, high IL 2 concentrations were required, in association with soluble OKT3 mAb, to induce the formation of IL2R α/β heterodimers, while later, low IL2 concentrations were sufficient to promote cell growth. When added during the initial phase, TU27 mAb directed at the IL2 binding site of IL2R β chain substantially inhibited the appearance of functional high‐affinity IL2R. Lo‐Tact‐1 mAb directed at the IL2 binding site of the IL2R α chain had only a marginal effect. Strong induction of IL2R α mRNA occurred within 3 days upon OKT3 and IL2 stimulation even in the presence of Lo‐Tact‐1 mAb, but not in the presence of TU27 mAb. OKT3 alone failed to induce significant IL2R α gene transcription and that induced by IL2 alone was very weak. The constitutive expression of IL2R β mRNA was visualized in resting T cells. It remained at a rather stable level, at least during the initial stimulation period which was examined herein.

Given the fact that OKT3 alone was ineffective in up‐regulating IL2R β mRNA expression and that pre‐incubation of the cells with OKT3 alone did not allow them to respond to high concentrations of IL2, it is highly probable that isolated IL2R β chains constitutively expressed by CD8+ T cells (the main reactive cells in this system) are primarily responsible for the initial interaction of IL2 with these cells. Such an interaction will result in the formation of high‐affinity IL2R and in the initiation of cell proliferation provided that a CD3‐derived co‐signal is simultaneously delivered to the cells.
5‐Azacytidine inhibits the lpr gene‐induced lymphadenopathy and acceleration of lupus‐like syndrome in MRL/MpJ‐lpr/lpr mice
Authors: Yoshida Haruyoshi , Yoshida Michiko , Merino Ramon , Shibata Takanori , Izui Shozo
Published: March 2007

MRL/MpJ‐lpr/lpr mice spontaneously develop a lupus‐like autoimmune disorder characterized by massive proliferation of T cells and rapidly fatal immune complex glomerulonephritis. We evaluated the therapeutic effect of 5‐azacytidine (5AC), a cytidine analogue known as an inhibitor of DNA methylation, in MRL/MpJ‐lpr/lpr mice. Intraperitoneal injection of 5AC (50 μg, twice a week) starting from 6 weeks of age retarded the development of lymphadenopathy and autoimmune syndrome. Its beneficial effects included: (a) increased life‐span, (b) diminution of lymphadenopathy and splenomegaly, (c) reduction in circulating levels of autoantibodies such as anti‐DNA and rheumatoid factors, and (d) suppression of lupus glomerulonephritis. However, similar treatment in BALB/c mice did not affect the development of IgG anti‐human IgG antibody responses. These results suggest that the protective effect of 5AC is related to the inhibition of the lpr gene‐induced T cell proliferation, thereby suppressing the autoimmunity‐accelerating effect mediated by the lpr gene.
The requirement of intrathymic mixed chimerism and clonal deletion for a long‐lasting skin allograft tolerance in cyclophosphamide‐induced tolerance
Authors: Eto Masatoshi , Mayumi Hisanori , Yoshikai Yasunobu , Nishimura Yousuke , Nomoto Kikuo
Published: March 2007

Mechanisms of cyclophosphamide (CY)‐induced tolerance were studied. When C3H/He Slc (C3H; H‐2k, Mls‐1b) mice were primed i.v. with 1 × 108 viable spleen cells from H‐2‐identical AKR/J Sea (AKR; H‐2k, Mls‐1a) mice and treated with 200 mg/kg of CY 2 days later, a long‐lasting skin allograft tolerance to AKR was established. When [C57BL/6 Sea (B6; H‐2b, Mls‐1b) × AKR]F1 (B6AKF1) cells were used as the tolerogen, however, only a moderate, but not long‐lasting, skin tolerance to AKR was observed.

In the C3H mice treated with AKR cells and CY, the intrathymic clonal deletion of Vβ6+ T cells, which are strongly correlated with reactivity to Mls‐1a antigens, was observed in the chimeric thymus on day 35, although neither the clonal deletion of Vβ6‐bearing T cells nor the mixed chimerism was observed in the thymus on day 14. In the C3H mice treated with B6AKF1 cells followed by CY, however, neither the clonal deletion of Vβ6+ T cells nor the mixed chimerism was observed in the thymus throughout the test period. In the lymph nodes of the C3H mice treated with AKR cells and CY, only CD4+Vβ6+ T cells, but not CD8+Vβ6+ T cells, had selectively decreased by day 14, and they were hardly detectable on day 35. The selective decrease of CD4+Vβ6+ T cells in the lymph nodes was also observed by day 14 when B6AKF1 cells were used as the tolerogen, although CD4+Vβ6+ T cells gradually increased on day 35, at which time almost all skin grafts from AKR had already been rejected. These results strongly support the necessity of the intrathymic mixed chimerism and clonal deletion of donor‐reactive T cells for a long‐lasting skin allograft tolerance in CY‐induced tolerance.