bluuebunny/crossref_metadata_2025 huggingface dataset:
Complement Receptor Type 2 Mediates Infection of the Human CD4‐Negative Raji B‐Cell Line with Opsonized HIV
Authors: BOYER V. , DELIBRIAS C. , NORAZ N. , FISCHER E. , KAZATCHKINE M. D. , DESGRANGES C.
Published: July 2006

Boyer V, Delibrias C, Noraz N, Fischer E, Kazatchkine MD, Desgranges C. Complement Receptor Type 2 Mediates Infection of the Human CD4‐Negative Raji B‐Cell Line with Opsonized HIV. Scand J Immunol 1992;36:879‐83

Opsonization of the HTLV‐RF and HTLV‐IIIB strains of HIV‐1 with normal human HIV seronegative serum under conditions that allow complement activation resulted in the productive infection of cells of the Raji B lymphoblastoid cell line. Under the same experimental conditions, no infection of Raji cells was observed with unopsonized virus. Infection of Raji cells with complement‐opsonized HIV‐1 was totally suppressed by preblocking the function of CR2 (the C3dg receptor, CD21) on the cells with a monoclonal anti‐CR2 antibody cross‐linked with rabbit F(ab')2 anti‐mouse immunoglobulin antibodies. Infection of Raji cells occurred independently of CD4 since the cells lacked the expression of CD4 antigen and of CD4 transcripts. Thus, Raji cells may be infected with complement‐opsonized HIV independently of CD4 and in the absence of antibodies. By mediating and/or enhancing HIV infection, complement and complement receptors contribute to extend the range of target cells to the virus and may increase infection in patients with a low viral load.
Phagocytosis following Translocation of the Neutrophil b‐Cytochrome from the Specific Granule to the Plasma Membrane is Associated with an Increased Leakage of Reactive Oxygen Species
Authors: LUNDQVIST H. , KARLSSON A. , FOLLIN P. , SJÖLIN C. , DAHLGREN C.
Published: July 2006

The effect of neutrophil b‐cytochrome translocation on the respiratory burst activation generated during phagocytosis of yeast particles was investigated. Secretion of neutrophil specific granules was induced by the calcium ionophore ionomycin prior to phagocytosis. The secretory process is associated with a translocation from the specific granules to the plasma membrane of the respiratory burst b‐cytochrome. Respiratory burst activity was measured as release of hydrogen peroxide in the absence of azide (extracellular leakage) and in the presence of azide (total produclion). The subcellular localization of the b‐cytochrome was found to affect the extracellular release of hydrogen peroxide in that a plasma membrane localization was associated with a significantly increased release during phagocytosis. It should be pointed out, however, that most of the hydrogen peroxide, both in control and in ionomycin‐treated cells, is produced intracellularly, probably in the phagosomes.
T‐Cell Receptor Identification of an Oligodendrocyte‐Specific Autoreactive Cytotoxic T‐Cell Clone Without Self Restriction
Authors: JEWTOUKOFF V. , AMZAZI S. , LEBAR R. , BACH M. A. , MARCHE P. N.
Published: July 2006

In addition to myelin basic protein (MBP) and proteolipid protein (PLP), oligodendrocyte (Od) membrane autoantigens, such as the glycoprotein M2/MOG, could participate in the pathogenesis of autoimmune demyelinating diseases of the central nervous system (CNS), such us experimental allergie encephalomyelitis (EAE) or multiple sclerosis (MS). We have described an Od‐specific autoreactive and cytotoxic T‐cell clone, named C2, which recognized M2/MOG without conventional MHC restriction. In order to analyse the Od/C2 interaction, we determined the α/β T‐cell receptor (TCR) variable region usages and structures of C2. Monoclonal antibody stainings of C2 and nucleotide sequences show that the α chain is composed of a Vα5 and a Jα identical to Jα18BBM 142 gene segments, and that the TCR β chain is composed of Vβ17a, Dβ2.1 and Jβ2.2 gene segments indicatmg that C2 used a conventional α/β TCR for M2/MOG recognition.
Membrane Expression and Function of Complement Receptors CR1 and CR3 on Neutrophils from HIV‐Infected Subjects: Modulation by rTNF‐α and rGM‐CSF
Authors: CAPSONI F. , MINONZIO F. , COLOMBO G. , ONGARI A. M. , BONARA P. , RIZZARDI G. P. , LAZZARIN A. , ZANUSSI C.
Published: June 2006

We evaluated membrane expression and function of complement receptors CR1 and CR3 on neutrophils from 27 HIV‐positive (HIV+) subjects (14 in the CDC class III and 13 class IV) as well as their modulation in vitro by recombinant tumour necrosis factor‐α (rTNF‐α) and granulocyte‐macrophage colony stimulating factor (rGM‐CSF). While CR1 was expressed at similar levels on neutrophils from controls and HIV+ subjects. CR3 expression was significantly higher in CDC class IV subjects than in healthy controls. CR1 and CR3 expression was significantly increased after treatment of neutrophils with both cytokines, without differences between controls and HIV+ subjects. Similarly, the superoxide anion (O2) production in response to C3‐coated zymosan (C3zy) was significantly enhanced on neutrophils from CDC class IV subjects when compared with controls. rGM‐CSF and rTNF‐α treatment significantly enhanced the spontaneous as well as C3zy‐stimulated O2 production by neutrophils from controls and CDC class III subjects, and induced an upward trend in the CDC class IV group. These results indicate that the neutrophils of HIV+ patients are preactivated in vivo but they also indicate that these cells may correctly respond to a subsequent particulate stimulus as well as to activating cytokines. Our findings suggest that desensitization or functional exhaustion of complement receptors are not implicated in the abnormalities observed on neutrophils from HIV+ patients.
Antigen‐Specific Increases in the Number of Splenocytes Expressing MHC Class II Molecules Following Restimulation with Antigen in Various Physical Forms
Authors: BERGSTRÖM‐MOLLAOGLU M. , LÖVGREN K. , ÅKERBLOM L. , FOSSUM C. , MOREIN B.
Published: June 2006

To understand how a presentation system for antigens initiates an immune response and why it has a strong adjuvant activity, a number of parameters need to be analysed. In this study the frequency of spleen cells expressing MHC class II (Ia antigen) was determined after immunization of mice and restimulation of their spleen cells, in vitro, with influenza virus envelope proteins in different physical forms, namely iscoms, micelles and virus particles.

All three forms of the antigen stimulated, in an antigen‐specific manner, an increased proportion of spleen cells expressing MHC class II in the restimulation experiments. The induction of increased MHC class II expression was at least partly dependent on antigen‐specific indction of IFN‐γ sinec anantibody to IFN‐γ partly inhibited the increase of MHC classII+ cells induced by iscom or by Concanavalin A. The iscom‐borne antigens were superior to micelles to prime the immune response in vitro, indicating a capacity to induce memory cells. This primed immune response was readily recalled in vitro, as measured by IFN‐γ production and an increased number of MHC class II positive cells.
H‐2 Class I Ld Antigen Positively Selects Different TCR Vβ Gene Products in CD8+ and CD4+ T Cells
Authors: TSCHERNING T. , REIMANN J. , CLAESSON M. H.
Published: June 2006

Expression of CD4+ or CD8+ determinants and ten different TCR Vβ genes was analysed by two‐colour flow cytometry in lymph node cells (LNC) of BALB/c and dm2 (a BALB/c Ld loss mutant) mice. TCR Vβ14 expression of CD8+ T cells and TCR Vβ7 and 14 of CD4+ T Cells were significantly more frequent in BALB/c than in dm2 LNC, whereas no differences were observed in the frequency distribution of TCR Vβ+ CD4‐CD8‐ double negative LNC from BALB/c versus dm2 mice. These results represent the first published evidence for positive selection of particular TCR Vβ genes by individual MHC class I molecules in non‐manipulated mice.
Multiple ICAM‐1 (CD54) Epitopes are Involved in Homotypic B‐Cell Adhesion
Authors: BLOEMEN P , MOLDRNHAUER G. , VAN DIJK M. , SCHUURMAN H.‐J. , BLOEM A. C.
Published: June 2006

Two monoclonal antibodies (MoAbs), F10.2 and F10.3. were selected for their ability to interfere in homotypic adhesion of human B cells Precipitation studies and binding to intercellular adhesion molecule I(CAM‐1, CD54) cDNA transfected COS cells revealed that both MoAbs are directed against ICAM‐1. The binding of MoAb F10.2 was inhibited by LB‐2, a MoAb recognizing the NH2‐terminal immunoglobulin‐like domain of ICAM‐1. This suggests that the epitope recognized by F10.2 is located on the first domain of the ICAM‐1. This suggests that the epitope recognized by F10.2 is located on the first domain of the ICAM‐1 molecule. Binding of the other MoAb. F10.3, was not inhibited by F10.2 nor by two other MoAbs mapping to the first domain of the ICAM‐1 molecule. The ability of F10.3 to bind to ICAM‐1 is influenced by glycosylation, suggesting that this epitope is located on one of the domains carrying possible glycosylation sites, i.e. domain 2,3 or 4. The ICAM‐1 epitopes recognized by F10.3 and LB‐2 or F10.2 co‐operated in homotypic adhesion of cells from the EBV cell line ML1. These results suggest that in addition to an epitope located on domain 1 of the ICAM‐1 molecule, another epitope whose exposure can be regulated by glycosylation is involved in homotype B‐cell adhesion of cell line ML1.
Presence of CD 16 on Endothelial Cells in Heart Transplant Rejection: an Immunohistochemical Study
Authors: TUIJNMAN W. B. , WIJNGAARD P. L. J. , VAN WICHEN D. , VAN DE WINKEL J. G. J. , CAPEL P. J. A. , SCHUURMAN H.‐J.
Published: June 2006

We studied the distribution of Fcγ RIII (CD16) in human lymphoid and non‐lymphoid tissue by immunohistochemistry and two‐colour immunofluorescence. In all tissues except stomach, skin, muscle and heart, infiltrating cells were stained. In tonsil and thymus, the CDI6 antibody CLBgran I labelled some cells with high endothelial morphology in T‐cell areas. Two‐colour fluorescence combination of CD 16 and antibody to Von Willebrand factor confirmed the endothelial nature of the CLBgran l‐positive cells. FcγRIII expression was also demonstrated by antibody CLBgran 11, which detects a product of the FcγRIII‐B gene of only the NAI haplotype. A series of 95 endomyocardial biopsies (FMB) taken after heart transplantation was evaluated for FcγRIII expression. In 18 eases FcγRIII was unambiguously detected on endothelial cells by CD16 antibody CLBgranI. There was a significant correlation between capillary CD16 expression and transplant rejection. We conclude that FcγR expression on endothelium represents endothelial activation found in immunopathological and inflammatory conditions.
Biliary Immune Response to Orally Presented Food Antigen, Ovomucoid, and its Potentiation by Cholera Toxin B Subunit
Authors: SUGITA‐KONISHI Y. , KUMAGAI S.
Published: June 2006

To clarify the biliary immune response against food antigen, we studied biliary antibody response lo intravenous and oral primary immunization with ovomucoid (OM)and the effects of cholera toxin B subunit (CTB) on the oral response in mice. Specific antibodies against OM were induced in biliary and serum immunoglobulin (Ig) A. IgGand IpM by intravenous (i.v.) administration of the antigen. However the antibodies were induced only in biliary Igs, but not in serum Igs, by oral intubation of the antigen. The higher levels of anti‐OM in bile than in serum observed in the oral group may favour the assumption that antigen‐stimulted lymphoid cells migrate to the liver, gall bladder or bile duct where they produce antibody. Both serum and biliary anti‐OM responses to oral immunization were potentiated remarkably by oral administration of CTB with the antigen, the IgM anti‐OM response being potentiated to the largest extent. In the CTB‐treated mice. the IgA anti‐OM level was higher in bile than in serum. Serum level of IgG anti‐OM was much lower in the CTB‐treated mice than in the i.v.‐immunized mice, but the biliary level of IgG anti‐OM in the CTB‐treated mice was comparable to that in the i.v.‐immunized mice. The relationship between serum and biliary IgA and IgG antibodies suggests that CTB potentiates biliary anti‐OM responses not solely through increasing systemic levels of the antibodies but through modulating the processes specific to mucosal presentation of antigen.
Dissociation of Autoaggression and Self‐Superantigen Reactivity
Authors: ANGEL GONZALO JOSE , DE ALBORAN IGNACIO M. , KROEMER G.
Published: July 2006

Self‐superantigens have been described as products of endogenous retroviruses of the mouse (‘minor lymphocyte stimulating loci’) that are capable of interacting without prior processing with conserved domains of TCR Vβ chains, causing the activation and deletion of most T cells expressing products of determined Vβ gene families [1–4], The fact that superanti‐gens activate a far higher percentage of T cells (1–20%) than conventional, peptidic antigens (< 0.1 %) provides the methodological advantage that the degree of clonal deletion may be measured by the analysis of the TCR repertoire using appropriate anti‐Vβ antibodies. Although much information on the spatio‐temporal organization of repertoire‐purging has been gathered by virtue of self‐superantigens, serious doubts exist as to the possibility that such structures serve as pathogenetically relevant autoantigens. Thus, certain inbred mice spontaneously develop autoimmune diseases, although they bear T‐cell repertoires that appear to be purged from self‐superantigen‐reactive Vβ products. In addition, therapeutic interventions targeted to Vβ gene products that are not specific for self‐superantigens are successful in preventing disease development. The lack of correlation between superantigen‐related Vβ deletions and autoimmune disease development is substantiated in further models of murine autoimmunity. Based on these observations, we formulate the hypothesis that self‐superantigen‐reactive T cells are not involved in the development of autoimmune diseases.
Serotonergic 5‐HT1a Receptors Regulate a Cell Contact‐Mediated Interaction between Natural Killer Cells and Monocytes
Authors: HELLSTRAND K. , HERMODSSON S.
Published: July 2006

Autologous monocytes irreversibly suppressed functions of human natural killer (NK) cells including baseline and lymphokine‐induced cytotoxicity, antibody‐dependent cellular cytotoxicity (ADCC). and interleukin‐2 (IL‐2)‐induced proliferation. The suppression of these NK‐cell functions was cell contact‐dependent and could be evoked only by purified monocytes, recovered directly from peripheral blood by countercurrent centrifugal elutriation (CCE). The presence of monocytes also induced the disappearance of CD16 and CD56 antigen on CD3‐ NK cells (CD3‐/16 +/56+ CD3‐/16‐/56‐). By contrast, T‐cell proliferation and the expression of CD3 on CD56‐ T cells were not susceptible to cell contact‐mediated suppression by monocytes. The biogenic amine serotonin abrogated monocyte‐induced suppression of NK‐cell functions as well as down‐modulation of CD16/56 NK‐cell antigen. Serotonin thus markedly augmented baseline and lymphokine‐induced NK‐cell cytotoxicity. ADCC, and NK‐cell proliferation, and maintained the expression of NK‐cell surface antigens in the presence of elutriated monocytes. The effect of serotonin was mediated by 5‐HT1A‐type serotonin receptors (5‐HT1aR) as indicated by mimicry exerted by 5‐HT1AR ugonists such as 8‐OH‐DPAT and (+)‐ALK, partial antagonism by the 5‐HT1AR antagonists pindolol and cyproheptadine. and lack of antagonism by the 5‐HT2R antagonist ketanserin or the 5‐HT3R antagonist ondansetron. Our data are suggestive of a cell‐lo‐cell‐mediated mechanism by which monocytes down‐modulate NK‐cell function and phenotype and its serotonergic regulation.
The Secretion of the Third Component of Complement (C3) by Human Polymorphonuclear Leucocytes from both Normal and Systemic Lupus Erythematosus Cases
Authors: FARIED H. F. , TACHIBANA T. , OKUDA T.
Published: July 2006

Recently, murine peritoneal exudate polymorphonuclear leucocytes (PMNs) have been proved to secrete complement C3. In this report we show the secretion of C3 by normal human blood PMNs. ELISA assay was used to detect secreted C3 in culture supernatants of PMNs, while immunoperoxidase staining was used for intracellular C3 detection. 12‐o‐tetradecanoyl phorbol 13 acetate (TPA) had a flushing effect on C3 secretion by PMNs but not tinacrophages, suggesting a special C3 storing capability in PMNs. Dioctanoyl glycerol, mezerein and calcium ionophore A23187 caused the same marked increase in C3 secretion by PMNs. This suggests the contribution of protein kinase C and the calmodulin pathway in the mechanism of C3 secretion, similar to murine peritoneal exudate PMNs. In some cases of systemic lupus erythematosus, C3 secretion by blood PMNs was increased but no similar response to TPA could be detected.
Recombinant Human Tumour Necrosis Factor‐α (rhTNF‐α) and rhTNF‐α Analogue Enhance Amyloid Deposition in the Syrian Hamster
Authors: NIEWOLD Th. A. , GRUYS E. , ARAKAWA T. , SHIRAHAMA T. , KISILEVSKY R.
Published: July 2006

Tumour necrosis factor‐α (TNF‐α) is one of the cytokines that stimulate the production of serum amyloid A (SAA), the precursor of AA amyloid. The role of TNF‐α in amyloidogenesis was investigated in experimental hamsters using purified recombinant human TNF‐α (rhTNF‐α) and rhTNF‐α analogue different from the normal molecule by two amino acid substitutions. Daily injections of 1 μg rhTNF‐α resulted in elevated SAA levels but even in the presence of amyloid enhancing factor (AEF) no amyloid was deposited, indicating that apart from the AEF and one particular SAA stimulating factor an additional factor is needed to result in amyloid deposition. This factor is generated by repeated injections of E. coli lipopolysaccharide (LPS).

A single intraperitoneal injection of 12,5 μg or more of rhTNF‐ä followed by seven daily subcutaneous injections of LPS resulted in enhanced amyloid deposition. Heat denaturation of rhTNF‐α did abolish its AEF activity. The rhTNF‐α analogue, having one‐fifth of the cytotoxic activity of the normal rhTNF‐α, showed a similar reduction in its SAA‐inducing capacity and its amyloidogenicity. This suggests the AEF activity to be closely related to TNF‐α activity. However, poly(I)poly(C) (a potent inducer of IL‐6) also showed AEF activity, suggesting that not a single cytokine but rather a certain combination of different cytokines could be decisive in AA amyloidogenesis.
Tetranectin: a Novel Secretory Protein from Human Monocytes
Authors: NIELSEN H. , CLEMMENSEN L , KHARAZMI A.
Published: July 2006

Tetranectin is a recently described human plasma protein, which is found in most secretory cells throughout the body, including neutrophils. We present evidence for the presence of tetranectin in human monocytes and macrophages as well, and that these cells upon adherence or weak stimulation release a 20 kDa protein identified as tetranectin by immunoblotting. The amount of tetranectin released is 3–18 ng/h/106 monocytes. The possible influence of tetranectin on cellular functions was tested in migration and oxidative metabolism assays, Monocyte spontaneous migration was significantly stimulated by preincubation with purified tetranectin, whereas chemotactic and chemiluminescence responses to fMLP and C5a were unchanged, Neutrophil functions were not affected. It is concluded that tetranectin is secreted from human mononuclear phagocytes upon weak stimulation, and that the secreted tetranectin facilitates spontaneous migration of these cells.
Fibronectin at the Lymphocyte Surface. Evidence for Activation‐Dependent Binding to VLA4 and VLA5 Integrins
Authors: HAUZENBERGER D. , SUNDQVIST K. G.
Published: July 2006

The surface of in vitro cultured fixed and viable human T lymphocytes and certain T‐cell lines was found to react with different monoclonal anti‐fibronection (FN) antibodies as revealed by ELISA, immunocyto chemistry and FACS analysis. SDS‐PAGE showed that anti‐FN antibodies defined a high molecular weight lymphocyte component which could be iodinated using the lactoperoxidase method and which had gelatin binding capacity. FACS analysis showed that the reactivity of anti‐FN antibodies with lymphocytes was most pronounced in activated cells and increased during the culture period. By contrast, FACS analysis revealed equal high expression of the VLA4 and VLA5 integrins on freshly purified as well as on mixed lymphocyte culture (MLC) activated cells, Freshly purified lymphocytes and lymphocytes cultured in vitro overnight did not bind 3H‐labelled FN in solution whereas MLC‐activated cells were capabie of 'spontaneous’binding of such [3H]‐FN. However, brief 12‐o‐tetradecanoylphorbol‐13‐acetate (TPA) exposure rendered freshly purified lymphocytes capable of binding soluble FN. These interactions of the lymphocytes with 3H‐labelled FN in solution could be almost completely blocked by monoclonal anti‐VLA4 and VLA5 antibodies. These results indicate that activated T cells express fibronectin at their surface under‘normal’culture conditions. Althotigh both freshly purified and MLC‐activated lymphocytes have equal expression of the integrins VLA4 and VLA5, only activated cells are capable of 'spontaneous’binding FN in solution via an integrin‐mediated process, probably via an increase in the affinity of these receptors for FN.
Physically Damaged Extracellular Matrix Induces TNF‐α Secretion by Interacting Resting CD4+ T Cells and Macrophages
Authors: HERSHKOVIZ R. , CAHALON L. , GILAT D. , MIRON S. , MILLER A. , LIDER O.
Published: July 2006

T lymphocytes and macrophages (Mø) are seen to accumulate at sites of lesions in blood vessel walls, suggesting that these cells may contribute to the initiation of the local inflammatory reaction. Tumour necrosis factor‐α (TNF‐α), a cytokine produced by both cell types, plays a major role in inflammatory reactions, in blood vessel formation, in thrombosis and in atherosclerosis. We now report that secretion of TNF‐α by CD4+ T cells and Mø can be induced in vitro in the absence of antigen, in an MHC‐II‐independent manner by immobilized extracellular matrix (ECM), Moreover, the level of TNF secretion is greatly enhanced in the presence of physically damaged ECM (dECM), This mode of TNF secretion is regulated primarily by the fibronectin or laminin glycoprotein components of ECM, Thus, a multicellular interaction with ECM proteins exposed as a consequence of vascular wall injury can serve to signal the secretion of TNF‐α by both cell types which induces the recruitment of additional immune cells to the developing lesion.
Expression of β2m‐Free HLA Class I Heavy Chains in Neuroblastoma Cell Lines
Authors: MAROZZI A. , MENEVERI R. , BUNONE G. , SANTIS C. DE , LOPALCO L. , BERETTA A. , AGRESTI A. , SICCARDI A. G. , VALLE G. DELLA , GINELLI E.
Published: July 2006

Flow cytometry with the specific monoclonal antibody (MoAb) L31 was used to analyse the expression of HLA class I heavy chains not bound with β2‐microglobulin (β2m) by neuroblastoma (NB) cell lines IMR‐32 and LA‐N‐1. The cells, which express barely detectable amounts of β2m‐free (L31‐positive molecules) and β2m‐complexed HLA class I antigens (W6.32‐ and BBM. I‐reactive molecules), expressed MHC class I molecules not bound to light chains upon differentiation with either retinoic acid or serum starvation. The expression was not accompanied by an increase of surface heterodimers. Conversely, recombinant interferon‐γ (rIFN‐γ) treatment led IMR‐32 and LA‐N‐1 cells to almost exclusively express β2m‐complexed HLA class I heavy chains. Surface β2m‐free MHC class I molecules displayed a molecular mass of ~45 kDa and did not bind exogenously added β2m. No changes in the synthesis of either HLA class I and β2m mRNAs or of L31 proteins were observed in differentiated NB cells, thus suggesting that the surface exposure of unusual HLA class I antigens is regulated post‐translationally. These findings indicate that, in addition to activated lymphocytes, the surface expression of β2m‐free class I heavy chains is a feature of other cell types, such as NB cells.
Modulation and High Frequency Expression of Autoantibody‐Associated Cross‐Reactive Idiotypes linked to the VhI Subgroup in CD5‐Expressing B Lymphocytes from Patients with Chronic Lymphocytic Leukaemia (B‐CLL)
Authors: SHOKRI F. , MAGEED R. A. , RICHARDSON P. , JEFFERIS R.
Published: July 2006

Leukaemic B cells from patients with chronic lymphocytic leukaemia (B‐CLL) are known to express the pan T‐cell marker CD5 and a restricted set of immunoglobulin (Ig) variable region heavy (Vh) and light (VL) chains encoded by germline or minimally mutated germline genes. We have studied surface expression of certain VH and VK gene products on peripheral blood B lymphocytes from 23 patients with B‐CLL, using a panel of monoclonal antibodies (MoAbs) recognizing germline encoded cross‐reactive idiotypes (CRI) associated with VHI (G6, G8), VHIII (B6, D12), VKIIIb (17–109) and an epitope linked to the VKIII light chain subgroup (C7). While only 1.7–3.2% of peripheral blood B lymphocytes from normal individuals expressed the VHI‐associated CRI (VhI‐CRI), these CRI were expressed on virtually all the leukaemic B cells from 17–22% of the CLL patients. The VHIII‐associated CRI (VHIII‐CRI), however, were found in 8.5–13% of the CLL B cells. Fifty per cent of the IgMK‐expressing CLL cells (7/14) expressed the VRIII light chain subgroup of which only one expressed the VKIIIb‐associated CRI (VKIIIb‐CRI), 17–109. The anti‐VHI‐associated CRI antibodies were used to study their regulatory effect on in vitro Ig synthesis by the leukaemic cells. A significant suppression of spontaneous and mitogen‐driven Ig production was observed in all cases studied. These results demonstrate an over‐expression of VHI and VKIII gene products in B‐CLL and suggest that B cells expressing these CRI are particularly susceptible to lymphoproliferative stimuli. The anti‐CRI antibodies can be used to modulate Ig production by the leukaemic cells and may be of potential value for selective immunotherapy.
IFN‐γ is directly Cytostatic to the Extracellular Form (Promastigote) of Leishmania donovani
Authors: BHATTACHARYA S. , MANNA P. P , BANDYOPADHYAY S.
Published: July 2006

We investigated the effect of various human cytokines on the in vitro growth of Leishmania donovani (L. donovani) promastigotes. rhIFN‐α, rhIFN‐β, rhIL‐1, rhIL‐2, rhIL‐3, rhIL‐4, rhIL‐6 and rhM‐CSF had no effect. By contrast. rhIFN‐γ was directly growth inhibitory to L. donovani promastigotes in a dose‐dependent manner. Anti‐IFN‐γ antibody, but neither anti‐IFN‐α nor an ti‐IFN‐β antibody, abolished this promastigote growth Inhibitory effect of rhIFN‐γ. L. donovani promastigotes were not lysed by rhIFN‐γ as determined by 51Cr‐release assay. These data indicate that rhIFN‐γ is cytostatic. not cytotoxic, to L. donovani promastigotes.
Modulation of Glucocorticosteroid Binding in Human Lymphoid, Monocytoid and Hepatoma Cell Lines by Inflammatory Cytokines Interleukin (IL)‐lβ, IL‐6 and Tumour Necrosis Factor (TNF)‐α
Authors: RAKASZ E. , GAL A. , BIRO J. , BALAS G. , FALUS A.
Published: July 2006

In order to elucidate the role of the inflammatory cytokines in regulating glucocorticosteroid binding (GCSB) and glucocorticosteroid receptor (GR) level we incubated a B‐cell line (CESS), a promonocytic cell line (U937) and a hepatoma cell Iine(HepG2)in the presence of varying concentrations of IL‐1β, IL‐6 and TNF‐α(for 24 h. Glucocorticosteroid binding was determined by the method of whole cell uptake', and the cellular appearance of the glucocorticosteroid receptor was detected by immunocytochemistry, A rise in the glucocorticosteroid binding was induced by all three cytokines. The increase in level of glucocorticosteroid receptors in the cells shown by immunocytochemistry was much more pronounced. However, antagonistic effects were demonstrated by both methods between IL‐6 and TNF‐α. and between IL‐1β and TNF‐α when they were applied simultaneously, in U937. Present data suggest that local imbalance in the ratio of these three cytokines in different pathological cases might influence the glucocorticosteroid sensitivity of the lymphocytes, monocytes and hepatocytes as target cells.
The Revised Amino Acid Sequence of Serum Amyloid A (SAA) Protein in Mink
Authors: SYVERSEN P. V. , SLETTEN K. , MARHAUG G. , HUSBY G. , LIUM B.
Published: July 2006

The revised amino acid sequence of mink protein SAA was shown to be composed of III amino acid residues. The protein has an insertion of eight amino acid residues compared with that reported earlier. Microheterogeneities were observed in positions 6, 10, 24, 27, 67 and 71. The amino acid sequence is in accordance with the SAA mink cDNA sequences, except for the phenylalanine in position 6. The data indicate a third SAA gene in mink.
Preferential Rearrangements of the VγI Subgroup of the γ‐Chain of the T‐Cell Antigen Receptor to Jγ2Cγ2 Gene Segments in Peripheral Blood Lymphocyte Transcripts from Normal Donors
Authors: MATHIOUDAKIS G. , CHEN P.‐F. , LI Y.‐D. , CHERNAJOVSKY Y. , PLATSOUCAS C. D.
Published: July 2006

To investigate whether there are preferential VJC gene rearrangements of the γ‐chain of the human T‐cell antigen receptor (TCR), we amplified and sequenced γ‐chain TCR transcripts from peripheral blood lymphocytes from adult normal donors. cDNA was synthesized from total RNA and amplified by the polymerase chain reaction (PCR) using 5’primers specific for either the VγI or the VγII subgroups of the γ‐chain of the TCR. The amplified cDNAs were then cloned and sequenced. The majority (approximately 83%) of the cDNAs employing V‐I subgroup gene segments rearranged to Jγ2 (Jγ2.1 or Jγ2.3) Cγ2 gene segments. This was in contrast to the predominant rearrangement of the VγII subgroup (Vγ9) to JγL2CγL The remaining 13% of the cDNAs employing VγI subgroup gene segments rearranged to JγLlCγl or JγL3Cγl. There was significant N diversity as well as imprecise joining at the VJ junction, γδ5 TCR utilizing the Cγ l gene segment are disulfide‐linked, whereas those utilizing the Cγ2 gene segment are non‐disulfide‐linked. These results demonstrate that peripheral blood γ‐chain transcripts exhibit preferential rearrangements of VγI subgroup gene segments to Jγ2(2.1,2.3)Cγ2 gene segments. By contrast, VγII subgroup (Vγ9) transcripts exhibit rearrangements to Jγ1.2Cγ1.
Test for Ability of Decay‐Accelerating Factor (DAF, CD55) and CD59 to Alleviate Complement‐Mediated Damage of Xeno‐Erythrocytes
Authors: MIYAGAWA S. , SHIRAKURA R. , MATSUMIYA G. , NAKATA S. , MATSUDA H. , HATANAKA M. , MATSUMOTO M. , KITAMURA H. , SEYA T.
Published: July 2006

We investigated the susceptibility to human complement (C) of xeno‐erythrocytes into which phosphatidylinositol (PI)‐anchored human C regulatory protein, decay‐accelerating factor (DAF) or CD59 had been incorporated. Erythrocytes of sheep (Esh), swine (Esw), dog (Edg), and guinea pig (Egp), unsensitized with human natural antibody (Ab), were used as xeno‐target. C‐mediated lysis of erythrocytes (E) was induced in both classical and alternative pathways in parallel with the density of the sensitized Ab, except for Egp. The efficacy of DAF/CD59‐mediated protection of the xeno E from human C, however, differed among these E species. In both classical and alternative pathways, Esh or Esw, which are non‐activator surfaces, were protected by the incorporated DAF or CD59, DAF being more effective than CD59. On the other hand, CD59 was more effective than DAF in both pathways in protection of Egp, which is an alternative pathway activator.

To elucidate this different behaviour of DAF and CD59, C3 step inhibition by the incorporated DAF or CD59 was measured. DAF was effective in the suppression of classical pathway‐mediated C3 deposition in Esh, Esw and Egp, but not in Edg, while CD59 exhibited negligible effects in this regard. Next, inhibition of the lysis by CD59 was tested by haemolytic assay. CD59 did not block the C5b‐8‐mediated lysis in any xeno E. It also barely blocked C5b‐9‐mediated lysis, except in the case of Egp, in which CD59 partly blocked C9 attack. Membrane constituents on targets other than the incorporated complement inhibitors may be a crucial factor in the induction of cytolysis and, presumably, in hyperacute rejection.
Defective Calcium‐Dependent Signal Transduction in T Lymphocytes of Ataxia‐Telangiectasia
Authors: KONDO N. , INOUE R. , NISHIMURA S. , KASAHARA K. , KAMEYAMA T. , MIWA Y. , I P. R. LORENZO , ORII T.
Published: July 2006

T‐cell functions of two patients with ataxia‐telangiectasia were investigated. Patients with ataxia‐telangiectasia had reduced percentages of circulating CD3+ cells and CD4+ cells, although neither patient had a reduced percentage of circulating CD8+ cells. The proliferative responses and interleukin‐2 production of peripheral blood mononuclear cells to T‐cell mitogens were reduced in the patients. The intracellular calcium concentration in T cells or CD4+ cells from both patients was only slightly increased after phytohaemagglutinin stimulation. Moreover, the concentration after OKT3 stimulation was not or only slightly increased in T cells or CD4+ cells from both patients. Our results suggest that the functional defect of T cells is caused by defective Ca2+‐dependent signal transduction through the CD3 complex of the surface in T cells of ataxia‐telangiectasia.
Secretion of IL‐2, IL‐3, IL‐4, IL‐6 and GM‐CSF by CD4+ and CD8+ TCRαβ+ T‐Cell Clones derived early after Allogeneic Bone Marrow Transplantation
Authors: BRUSERUD Ø. , EHNINGER G. , HAMANN W. , PAWELEC G.
Published: July 2006

Secretion of different cytokines may be an important T‐cell effector mechanism for bone marrow engraftment, graft versus host disease and graft versus leukaemia effects after allogeneic bone marrow transplantation (BMT). Cytokine secretion and autocrine proliferative capacity of T‐cell clones derived from leukaemia patients 3–6 weeks after allogeneic bone marrow transplantation were investigated. Only a minority of post‐transplant T‐cell clones (23/120; 19%) was capable of undergoing autocrine proliferation. By contrast, 21/65 (32%) normal control clones from the marrow donors derived under the same conditions were autocrine proliferative. All clones were interleukin‐2 (IL‐2) responsive. A majority (12/17; 71%) of autocrine proliferating post‐transplant clones secreted detectable IL‐2. Compared with control clones, CD4+ T‐cell clones derived early after BMT produced decreased levels of interleukin‐4 (IL‐4) and interleukin‐6 (IL‐6), whereas secretion of interleukin‐3 (IL‐3) and granulocyte/macrophage colony‐stimulating factor (GM‐CSF) showed no significant difference. The small number (n = 8) of post‐transplant CD8+ clones showed decreased production of IL‐3, IL‐4 and IL‐6 compared with control clones, but normal secretion of GM‐CSF. Neither CD4+ nor CD8+ T‐cell clones secreted interleukin‐7 (IL‐7).
Rheumatoid Inflammatory T‐Cell Clones express mostly Th1 but also Th2 and Mixed (Th0‐Like) Cytokine Patterns
Authors: QUAYLE A. J. , CHOMARAT P. , MIOSSEC P. , KJELDSEN‐KRAGH J. , FØRRE Ø. , NATVIG J. B.
Published: July 2006

This study was performed in order to characterize whether T cells from rheumatoid synovial inflammation belong to the Th1‐ or Th2‐like functional subsets. Cytokine production was studied in 26 CD4+αβ+ and 2 CD8+αβ T‐cell clones from the synovial fluid, the synovial membrane and peripheral blood of 5 patients. Fifteen of the CD4+ clones were raised against various mycobacterial antigens and 11 CD4+ clones and 2 CD8+ clones were raised unspecifically using PHA and/or IL‐2. The specificities of these clones are not known. In the mycobacterial antigen‐specific group, all CD4+’αβ T‐cell clones produced IFN‐γ at high levels, while the production of IL‐4 was generally absent or low (< 1 ng/ml), consistent with a Thl‐like profile. Some of these clones, however, also produced various amounts of IL‐10 which has been regarded as a Th2 product but can be produced also in lower amounts by Thi cells. One HSP‐65‐specific clone produced levels of IL‐4 and IL‐10 in the same order as that of IFN‐γ, thus appearing to be Th0‐like. Among the 11 unspecific CD4+ clones, 7 showed a Thl‐like pattern but with lower levels of IFN‐γ than the antigen‐specific clones. However, three clones did not produce any IFN‐γ activity but produced IL‐4 and one of them also produced distinct amounts of IL‐10, compatible with a Th2‐like pattern. In addition, one of the clones also showed an almost equally strong IFN‐γ and IL‐4 production, thus most likely representing a Th0‐like clone.
Liquid‐Liquid Partition Chromatography as a Method to Examine Surface Properties of Antibodies and Antigen‐Antibody Complexes
Authors: ANDERSSON K. , WINGREN C. , HANSSON U.‐B.
Published: July 2006

We demonstrate liquid‐liquid partition chromatography in aqueous two‐phase systems (LLPC) as a simple method for examining the surface properties of immunoglobulins and antigen antibody complexes in solution. LLPC separates molecules with respect to the properties of the exposed surfaces. As an example, the method may be used to detect changes in the conformation of IgG following chemical modification like acylation or iodination. We have studied the partitioning of antibodies and antigen antibody complexes, modelled by rabbit antibodies against three human serum proteins, in aqueous polyethylene glycol/dextran two‐phase systems at pH 7. Analysis of both polyclonal and monoclonal antibodies against various antigens suggested that the partition properties of immunoglobulins are related mainly to their antigen specificity and not to subclass‐specific structures. Furthermore, experiments indicated that changes in the surface properties of antigen and/or antibody following complexation may be detected. Thus, LLPC may prove to be a new way of studying the relation between antibody structure and function in solution.
Heterogeneity of the TCR Repertoire in Synovial Fluid T Lymphocytes Responding to BCG in a Patient with Early Rheumatoid Arthritis
Authors: WILSON K. B. , QUAYLE A. J. , SULEYMAN S. , KJELDSEN‐KRAGH J. , FØRRE Ø. , NATVIG J. B. , CAPRA J. D.
Published: July 2006

T lymphocytes have been implicated in the pathogenesis of rheumatoid arthritis. Interestingly, many of the activated T cells isolated from the synovial fluid of individuals with rheumatoid arthritis react with antigens from Mycobacterium tuberculosis or BCG. This response is seen to a much lesser extent in the peripheral blood of these patients. To investigate the nature of the T‐cell response to BCG in RA, we isolated T cells from the synovial fluid of a patient with early‐stage rheumatoid arthritis, stimulated them with BCG and cloned by limiting dilution. Staining with monoclonal antibodies specific for different Vβ gene families revealed a statistically significant greater proportion of synovial‐derived T‐cell clones expressing the Vβ8 gene family product compared with peripheral blood clones. While the antigen specificity of some of the clones could not be determined, several of the clones displayed distinct antigen reactivities. Sequencing the TCR P chain genes of these T cells suggested that although the Vβ8 gene products appeared to be over‐represented in these BCG‐specific clones, each clone utilized distinct Jβ gene segments and used N segment addition to different extents. In addition, no common motifs were identified in the β chain CDR3s of the clones sequenced. Analysis of bulk cultured BCG‐specific SF T cells and unstimulated peripheral blood T cells for Vβ8 gene expression also revealed a large amount of diversity within the CDR3 region. Thus, the T‐lymphocyte response to BCG in this patient with early rheumatoid arthritis appears to be quite heterogeneous.
In Vivo Depletion of Chicken T‐Cell Subsets
Authors: CIHAK J. , LÖSCH U. , HOFFMANN‐FEZER G. , CHEN C. H. , COOPER M. D. , ZIEGLER‐HEITBROCK H. W. L.
Published: July 2006

In the chicken three types of T‐cell receptors can be defined by monoclonal antibodies TCR1, TCR2 and TCR3, which recognize γδ T cells, and Vβ1‐ and Vβ2‐expressing αβ T cells, respectively. In the present report we have analysed means of selectively depleting the γδ T cells and the Vβ1 +αβ T cells.

γδ cells, which represent up to 66% of all T cells in blood of a 6‐month‐old chicken, can be effectively depleted by neonatal thymectomy (Tx) to levels as low as 1%. Immunohistology demonstrates a similar depletion in lymphoid organs while intestinal epithelium‐associated γδ T cells are affected by Tx to a lesser extent.

Vβ1‐bearing αβ T cells, which comprise about 80% of the αβ T cells, were depleted by embryonic and neonatal injection of the TCR2 antibody. In the thymus such treatment depleted only the Vβ1 +αβ T cells with high density expression of T‐cell receptor. Therefore, we thymectomized TCR2‐treated animals in order to prevent development of mature Vβ1+αβ T cells from the low density immature thymocytes. Treatment of chickens with a total of 22 mg of TCR2 antibody plus Tx reduced Vβ+αβ T cells from an average of 65% to 10% of all T cells. In these TCR2 antibody‐treated animals the Vβ2‐expressing αβ T cells become the predominant type of T cell (average 85%).
Murine APC Activation in the Xenogeneic MLC
Authors: BENFIELD M. R. , WITSON J. C. , ALTER B. J. , BACH F. H.
Published: July 2006

Purified human T cells proliferate in response to direct and indirect presentation of human alloantigens. However, until recently it was believed that human T cells could respond only indirectly to murine xenoantigens. We recently used the mixed leucocyte culture (M LC) to demonstrate that purified human T cells proliferate in response to direct presentation of murine xenoantigens by murine antigen‐presenting cells (APC) in the presence of human cytokines. We suggested that cytokines might function poorly across species barriers.

In this study, we demonstrate that although proliferation occurs in the presence of exogenously added cytokines, the precursor frequency of responding human T cells is much lower in a xenogeneic than in an allogeneic MLC. We demonstrate that human T cells also proliferate in response to murine APC in the presence of murine cytokines, and murine cytokines augment the proliferative response seen in a human anti‐human MLC, ruling out the possibility that an absolute cytokinc incompatibility exists between these species. We show that exogenously added human IL‐1 causes maximal proliferation of human T cells in response to murine xenoantigens only when added early in the culture. We further demonstrate that murine APC preincubatcd in human rIL‐1, and washed extensively, prior to use as stimulating cells, cause human T‐cell proliferation without the need for exogenously added cytokines. Finally, we noted that during interactions of human T cells and murine APC, little to no IL‐1 is produced, whereas after the addition of exogenous IL‐1, a marked increase in the production of IL‐1 is seen. These data suggest that during interactions between human T cells and murine APC, the murine cells do not receive adequate stimulation to produce sufficient costimulatory signals to allow proliferation of the human T cells.
Characterization of Stimulatory Surface Molecule Expression on Avian T Cells
Authors: KAPLAN M. H. , ALHASAN S. , ROSENSPIRE A. , SUNDICK R. S.
Published: July 2006

We have characterized a monoclonal antibody (AT389), produced by immunization of mice with 4‐day‐old avian Concanavalin A blasts, which recognizes a 38 40 kDa homodimer present on the surface of all chicken T cells. AT389 increased the spontaneous and IL‐2‐driven proliferation of 3‐day‐old T‐cell blasts. This antibody, in synergy with IL‐2, increased cellular proliferation and cell survival of T‐cell blasts over time. Together, these data suggest that AT389 recognizes a surface protein on avian T cells which may be related to known stimulatory surface markers on mammalian T cells.
Polyreactivity is a Property of Natural and Disease‐Associated Human Autoantibodies
Authors: HUREZ V. , DIETRICH G. , KAVERI S. V. , KAZATCHKINE M. D.
Published: July 2006

Polyreactivity was earlier recognized as a feature of naturally expressed autoantibodies in serum. In the present study, we have compared the reactivity on a panel of self antigens of affinity‐purified anti‐DNA and anti‐thyroglobulin (TG) IgG autoantibodies from the serum of patients with systemic lupus erythematosus (SLE) and autoimmune thyroiditis with their affinity‐purified counterparts isolated from the serum of healthy individuals. Anti‐DNA autoantibodies exhibited a similar degree of polyreactivity whether originating from patients or from healthy adults. Natural anti‐TG autoantibodies were also found to be polyreactive. Anti‐TG autoantibodies from patients with Hashimoto's thyroiditis showed little or no polyreactivity. Natural anti‐TG autoantibodies were equally polyreactive whether or not they belonged to a fraction of normal IgG that is connected through V regions with other IgG molecules from the same source. These results indicate that polyreactivity of autoantibodies is a feature that does not allow one to distinguish between natural and disease‐associated autoantibodies as well as between V‐region‐connected and unconnected autoantibodies.
B‐Cell Activation in Duodenal Mucosa after Oral Cholera Vaccination in IgA Deficient Subjects with or without IgG Subclass Deficiency
Authors: NILSSEN D. E. , FRIMAN V. , THEMAN K. , BJÖRKANDER J. , KILANDER A. , HOLMGREN J. , HANSON L. Å. , BRANDTZAEG P.
Published: July 2006

Alterations in duodenal Ig‐producing cells induced by two oral cholera vaccinations were studied by two‐colour immunofluorescence in mucosal tissue sections from adults with selective IgA deficiency (IgAD), cither with (n= 7) or without (n= 9) frequent infections, infection‐prone patients with combined IgAD and IgG subclass deficiency (IgGSD) (n= 7), and normal control subjects (n= 11). The proportion of IgG‐producing cells prior to immunization tended to be lower in the symptomatic IgAD subjects than in the clinically healthy ones. In the first subgroup the absolute number of IgG cells per intestinal length unit was significantly increased after immunization (P < 0.04), and this tendency was also observed in the healthy IgAD subjects (6/9) and in those with combined deficiency (5/7). Very few IgAD subjects responded with an increase of IgM‐producing cells. The normal controls responded variably in all major immunocyte classes, in the order IgA > IgG > IgM. Compared with these controls, the patients with combined IgAD and IgGSD showed significantly increased IgG1 (P < 0.01) and reduced IgG2(P < 0.006) proportions, which was in accordance with their serum subclass levels. Our study showed that oral cholera vaccination preferentially activates intestinal IgG‐producing cells in IgAD subjects. This result agreed with data recently obtained by ELISPOT in the same patients with regard to antibody‐forming cells specific for cholera toxin. Both methods suggested that IgG rather than IgM antibodies are elicited as compensation for a lacking IgA response. However, our overall results showed that intestinal B‐cell activation is quite variable after oral cholera vaccination. Although such vaccination might be of importance for enhancing mucosal immunity also in IgAD patients, a concurrent gut disease could possibly be aggravated by IgG‐mediated mucosal immunopathology in the absence of anti‐inflammatory IgA antibodies.