bluuebunny/crossref_metadata_2025_split huggingface dataset:
Defective interleukin 2 receptor expression is associated with the T cell disfunction subsequent to bone marrow transplantation
Authors: López‐Botet Miguel , De Landazuri Manuel O. , Izquierdo Manuel , Ramirez Ana , Figuera Angeia , Cámara Rafael , Fernández‐Rañada José 
Published: March 2007

AbstractIn the present work we have used monoclonal antibodies (mAb) as probes to attempt a dissection of the mechanisms underlying the immunodeficiency subsequent to bone marrow transplantation (BMT). To this end we have studied 19 allogeneic BMT recipients, analyzing the proliferative response of peripheral blood mononuclear cells (PBMC) after activation with either phytohemagglutinin (PHA), anti‐CD3 or anti‐CD 2 mAb. All patients presented normal proportions of CD2+ and CD3+ lymphocytes, as assessed by flow cytometry.Our results indicated that in most cases both CD 2 and CD 3‐mediated activation pathways were inefficient to trigger normal T cell proliferation. The addition of exogenous interleukin 2 (IL 2) did not restore in most cases the proliferative response, pointing out that additional defects contribute to the hyporesponsiveness. This was more evident in the group of patients studied during the first 6 months. To further dissect the T cell defect we analyzed the effect of a phorbol ester (phorbol myristate acetate, PMA), which activates protein kinase C, on the anti‐CD 3‐induced response. Our data showed that PMA synergized with anti‐CD 3 similarly to exogenous IL 2, and restored the proliferative response only in certain cases. The expression of IL 2 receptors (CD 25) as assessed by cytofluorimetry, after either PHA or anti‐CD 3 and PMA stimulation, was shown to be depressed, and the addition of IL 2 did not restore it. Finally, we observed that the early increase of intracytoplasmic Ca2+ after anti‐CD 3 stimulation was comparable to that detected in normal PBMC.Altogether these results indicate that a diminished CD 25 expression is associated with the T cell defect, and cannot apparently be attributed to an inability of the CD 3 molecule to transduce early activation signals thus suggesting that either protein kinase C itself or an as yet undefined metabolic step preceding IL 2 receptor expression is abnormal in variable proportions of T cells after BMT, and constitutes another manifestation of this complex immunodeficiency.
Discrimination of hepatocyte‐stimulating activity from human recombinant tumor necrosis factor α
Authors: Andus Tilo , Heinrich Peter C. , Bauer Joachim , Tran‐Thi Thuy‐Anh , Decker Karl , Männel Daniela , Northoff Hinnak 
Published: March 2007

AbstractThe involvement of tumor necrosis factor α (TNFα) in the regulation of acute‐phase protein synthesis is currently under discussion. In this study the effect of human recombinant TNFα on the regulation of the 4 acute‐phase proteins α2‐macroglobulin, albumin, α1‐proteinase inhibitor and α‐acute‐phase globulin was investigated in rat hepatocyte primary cultures. No changes in synthesis of any of the 4 proteins were observed. However, an acute‐phase response similar to that in vivo could be generated by conditioned media from human monocytes containing natural TNFα. This response remained unchanged after neutralizing TNFα activity by the addition of a specific antibody to TNFα. It is concluded that the hepatocyte‐stimulating activity synthesized by human monocytes is different from TNFα.
Cloned human CD3− lymphocytes with natural killerlike activity do not express nor rearrange T cell receptor gamma genes
Authors: Triebel Frédéric , Graziani Marita , Faure Florence , Jitsukawa Setsuko , Hercend Thierry 
Published: March 2007

AbstractHere we report the characterization of T cell receptor (TCR) gene activation in 14 CD3− cloned lymphocytes with natural killer‐like activity from different origins. No transcription of either α or β or γ genes is detected in any of these clones. All Jβ, Cβ clusters are in germ‐line configuration. The 5 presently described Jγ loci (JγP1, JγP, Jγ1, JγP2, Jγ2) are also in germ‐line configuration on each chromosome. These results indicate that several distinct populations of CD3− cloned NK cells do not use γ gene products as a recognition structure. Perhaps more importantly, these cells do not appear to be engaged in the earliest presently known stage of T lymphocyte differentiation, namely rearrangement at one of the Jγ loci.
Engineering of immunogenic peptides by co‐linear synthesis of determinants recognized by B and T cells
Authors: Borras‐Cuesta Francisco , Petit‐Camurdan Agnès , Fedon Yann 
Published: March 2007

AbstractThe potential of synthetic peptides as vaccines is restricted by their frequent lack of immunogenicity. As with haptens, coupling to a carrier protein is usually required to provide T cell help to anti‐peptide antibody‐producing B cells. In spite of their short length, a few natural or synthetic peptides are immunogenic: they all include both a determinant recognized by B cells and a proven or putative determinant recognized by T cells. We speculated that it should be possible to induce immunogenicity in peptide haptens by the inclusion of a well characterized determinant recognized by T cells. We thus synthesized two peptides, corresponding to different regions of the major protein VP6 of bovine rotavirus, co‐linearly linked to a peptide of influenza virus hemagglutinin which had been shown to induce T helper cells in BALB/c mice. Both peptides induced anti‐rotavirus antibodies and were more immunogenic than the corresponding bovine serum albumin‐conjugated peptides.
Interleukin‐HP1‐related hybridoma and plasmacytoma growth factors induced by lipopolysaccharide in vivo
Authors: Coulie Pierre G. , Cayphas Sylvie , Vink Anne , Uyttenhove Catherine , Van Snick Jacques 
Published: March 2007

AbstractSerum of lipopolysaccharide (LPS)‐treated mice was found to support the growth of interleukin‐HP1 (HP1)‐dependent hybridoma and plasmacytoma cell lines. This growth‐promoting activity, which was undetectable in normal serum, rose more than 1000‐fold within 2 h after i.v. injection of the toxin and disappeared in less than 1 day. It could be traced to a single component, which behaved like HP1 in sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and reverse phase high performance liquid chromatography, and was completely inhibited by a rabbit anti‐HP1 antiserum. The LPS‐induced factor was apparently not of T cell origin, as indicated by the strong activity found in the serum of LPS‐treated nude mice. In vitro, LPS also considerably enhanced the production by macrophages of a factor with similar characteristics.
Expression of the W6/32 HLA epitope by cells of rat, mouse, human and other species: critical dependence on the interaction of specific MHC heavy chains with human or bovine β2‐microglobulin
Authors: Jefferies Wilfred A. , MacPherson G. Gordon 
Published: March 2007

AbstractThe HLA class I epitope W6/32 is conformationally dependent on both heavy chain and β2‐microglobulin (β2M). Previously, the W6/32 epitope has been detected in humans and other primates as well as from bovine sources. Two controversial reports suggest the W6/32 epitope is constitutively expressed by either normal or transformed murine cells expressing the Db allele. Here we show that the appearance of the W6/32 epitope in murine cells results from the association of either the Db or Kd gene products with either bovine or human β2M. We use congenic mouse strains and hybrid H‐2 class I genes between Db and Kb to map the W6/32 epitope to particular amino acid residues in the α2 domain. Subsequently, we show that β2M exchange is not confined to murine or human cells in vitro but can be detected after β2M injection into a mouse. The data presented suggests that β2M exchange takes place at the cell surface under physiological conditions and indicates that MHC class I heavy chains are in an equilibrium between the bound and unbound form of β2M.
Control of prothymocyte proliferation by thymic accessory cells
Authors: Papiernik Martine , Penit Claude , Rouby Soumaya Ei 
Published: March 2007

AbstractAll thymocyte subpopulations derive from intrathymic precursors which are double negative (DN) for Lyt‐2 and L3T4 differentiation antigens. Although nearly half of DN cells express a receptor for interleukin 2 (IL2R), they respond poorly to IL2. DN cell proliferation can be obtained in the presence of various exogenous stimuli, but the in vivo signal for DN cell response to IL2 remains unclear. We show in the present report that phagocytic cells of the thymic reticulum are able to induce the proliferation of DN thymocytes in the presence of recombinant IL2 (rIL2). Cell‐to‐cell contact is needed for this effect. Antibodies directed against class I MHC antigens but not against class II can inhibit DN cell proliferation. DNA‐synthetizing cells were labeled by incubation with 10 μM bromodeoxyuridine either before or at various times during the culture period. Bromodeoxyuridine was then detected in the DNA of proliferating cells and/or their progeny already stained with anti‐Lyt‐2 and L3T4 antibodies. During the initial 16 h and independently of culture conditions, 16–25% of the cells expressed surface antigens and 50–65% of them derived from DN cells which were in S phase just before culture; these differentiated cells had a very short life span.In the second culture period, the presence of both rIL 2 and thymic accessory cells was necessary for cell survival. In these conditions, DN cell number and proliferation rate were constant and a low number of Lyt‐2+ and/or L3T4+ cells was continuously generated. Thymic accessory cells therefore appear to provide the signal(s) necessary for IL2‐induced proliferation of thymocyte precursors.Implications of these findings for normal in vivo intrathymic proliferation and differentiation are discussed.
Newly produced virgin B cells migrate to secondary lymphoid organs but their capacity to enter follicles is restricted
Authors: Lortan Jennifer E. , Roobottom Carl A. , Oldfield Susan , MacLennan Ian C. M. 
Published: March 2007

AbstractThe migration of recirculating B cells was compared with that of newly produced virgin B cells following passive cell transfer between congenic strains of rats differing in their kappa immunoglobulin light chain (χ) allotype. The number and location of donor B cells in the secondary lymphoid organs was determined at intervals following transfer by immunohistology using monoclonal antibodies specific for rat χ allotypes. Recirculating B cells were obtained from thoracic duct lymph while bone marrow from rats depleted of recirculating cells was used as a source of newly produced virgin B cells.B cells from both sources gained immediate access to extrafollicular areas of secondary lymphoid organs rich in interdigitating cells and T cells. However, in lymph nodes extrafollicular B cells were found adjacent to lymphatics and not in the central paracortex. By 8 h after transfer most B cells from thoracic duct lymph were found in follicles. However, the capacity of the bone marrow B cells to enter follicles was very limited. These results are interpreted in relation to previous observations concerning (a) the timing of virgin B cell recruitment into T cell‐dependent antibody responses, and (b) the role of B cells in antigen presentation.
Role of p150,95 in adhesion, migration, chemotaxis and phagocytosis of human monocytes
Authors: Keizer Gerrit D. , Te Velde Anje A. , Schwarting Roland , Figdor Carl G. , De Vries Jan E. 
Published: March 2007

AbstractThe leukocyte function‐associated antigen‐1 (LFA‐1), the C3bi receptor (CR3) and the p150,95 antigen belong to a family of leukocyte surface molecules consisting of bimolecular complexes with ä chains of 170 kDa, 165 kDa and 150 kDa, respectively, and a common β subunit with a mol. mass of 95 kDa. In order to determine the function of the p150,95 antigen on human monocytes and U937 cells, and to study the functional relationship between this antigen and LFA‐1 or CR3, we investigated the influence of monoclonal antibodies (mAb) directed against these cell surface molecules on the adhesive properties of these cells. The observation that anti‐β chain mAb strongly inhibited migration, chemotaxis, adhesion and phagocytosis of monocytic cells indicates a major role for LFA‐1 family antigens in monocyte functions. Detailed analysis with a panel of anti‐α chain antibodies demonstrated that both p150,95 and LFA‐1 mediate random migration whereas in contrast, p150,95 and CR3 were shown to be involved in the directed migration of monocytes to f‐Met‐Leu‐Phe. Furthermore, adhesion of monocytes to plastic surfaces or monolayers of endothelial cells as well as phagocytosis of latex particles was mediated by p150,95.The results demonstrate that, in spite of its relative low expression, the p150,95 glycoprotein is a major adhesion‐associated molecule expressed by human monocytic cells.
The cytosolic free calcium in anti‐μ‐stimulated human B cells is derived partly from extracellular medium and partly from intracellular stores
Authors: Dugas Bernard , Calenda Alphonse , Delfraissy Jean‐François , Vazquez Aimé , Bach Jean‐François , Galanaud Pierre 
Published: March 2007

AbstractThe inositol phospholipid metabolism and the increase in cytosolic free Ca2+ concentration ([Ca2+]i) into the cell are recognized as two important events in the anti‐μ‐induced B cell activation. The anti‐μ stimulation caused the [3H]inositol incorporation and also a rapid increase in [Ca2+]i from 85 nM to 285 nM. This signal returned to baseline a few minutes after stimulation. By using the fluorescent indicator quin‐2 we demonstrated that this [Ca2+]i uptake was derived part from extracellular medium and part from intracellular stores. Both EGTA (a calcium chelator) and TMB.8 (a drug which interferes with Ca2+ sequestration by smooth endoplasmic retiulum) partially suppressed the intracellular Ca2+ uptake and were fully inhibitory when added together. The role of Ca2+ from intracellular stores may also be evidenced in calcium‐free experiments, or in permeabilized experiments using exogenous inositol 1,4,5‐trisphosphate (IP3, the putative mobilizer of intracellular Ca2+). Preventing the increase in [Ca2+]i also prevents the apparition of early activation markers. These results are consistent with the hypothesis that the Ca2+ increase in B cells stimulated by anti‐μ is caused by the generation of IP3 during the phosphatidyl‐inositol metabolism and also by the entry of extracellular Ca2+ through the plasma membrane.
Immunoglobulin VH region genes of the mouse are organized in overlapping clusters
Authors: Blankenstein Thomas , Krawinkel Ulrich 
Published: March 2007

AbstractRestriction fragment length polymorphism has been compared between the Igh loci of C57BL/6 and MOLF/EI (Mus musculus molossinus) mice utilizing probes which detect the Cγ2b gene and genes from nine VH‐gene families. Distinct restriction site patterns were found for the CH genes and for VH families PC7183, Q52 and X24. VH families V31 and J558 showed identical patterns. Mixed patterns of identical and distinct bands were detected in VH families S107, J606, V3660 and VGAM3.8. This indicates that a recombination took place involving the Igh loci of a M. m. molossinus and a progenitor of the C57BL/6 strain. The breakpoint of recombination maps to the chromosomal region carrying VH families S107, J606, VGAM3.8 and V3660. VH families PC7183, Q52 and X24 map 3′ to the recombination breakpoint and proximal to the DH‐JH‐CH region, whereas VH families V31 and J558 accordingly map 5′ to the recombination breakpoint and distal to DH‐JH‐CH. This order of VH families was confirmed by deletion mapping utilizing hybridomas which are haploid either for the Ighb or for the Igha locus. The mapping data indicate that the VH families of the mouse are organized in overlapping clusters. This notion is confirmed by demonstration of the physical linkage of VH genes from families V31 and J558 in the Igha locus.
Cyclophilin binds to the region of cyclosporine involved in its immunosuppressive activity
Authors: Quesniaux Valérie F. J. , Schreier Max H. , Wenger Roland M. , Hiestand Peter C. , Harding Matthew W. , Van Regenmortel Marc H. V. 
Published: March 2007

AbstractAlthough several cytosolic proteins including calmodulin and cyclophilin have been shown to bind cyclosporine, the direct involvement of these proteins in the immunosuppressive activity of cyclosporine remains to be established. In the present study, a quantitative immunoassay for cyclophilin was developed which made it possible to compare its relative affinity for cyclosporine and any of its analogues. The binding of cyclophilin to cyclosporine coated on a solid phase was revealed by anti‐cyclophilin rabbit antiserum followed by antiglobulin‐enzyme conjugate. This reaction could be inhibited by addition of free cyclosporine or certain cyclosporine analogues. By studying the binding of cyclophilin to more than fifty cyclosporine derivatives modified singly on each of the eleven amino acid residues, it could be shown that cyclophilin binds to the residues of cyclosporine known to be critical for its immunosuppressive activity. These data identify cyclophilin as a highly discriminating stereospecific binding protein for cyclosporine.
Murine and human T11 (CD2) cDNA sequences suggest a common signal transduction mechanism
Authors: Clayton Linda K. , Sayre Peter H. , Novotny Jiri , Reinherz Ellis L. 
Published: March 2007

AbstractThe murine equivalent of the cDNA encoding the human T11 (CD2) sheep erythrocyte‐binding protein has been cloned. It codes for a putative transmembrane protein which is homologous to human T11. In contrast to immunoglobulins whose domains consist of anti‐parallel β sheets, we predict that mouse and human T11 external domains probably belong to the α/β protein folding class. The cytoplasmic region of T11 is a lengthy, proline‐rich semgent; secondary structural analysis predicts it to have a nonglobular conformation. This elongated tail could allow for interaction with multiple other intracellular proteins and may contain a cation‐binding site involved in T lineage activation.
Phorbol ester induces class II gene expression in pre‐B cell lines
Authors: Sarthou Pierre , Jouvain‐Marche Evelyne , Cazenave Pierre‐André , Le Guern Christian 
Published: March 2007

AbstractThe effect of phorbol myristate acetate on the induction of major histocompatibility complex class II gene expression was studied in four Abelson murine leukemia virus‐transformed pre‐B cell lines. In three cell lines, low concentrations of PMA (0.1–10 ng/ml) induced the expression of high levels of surface la molecules, and this effect was mediated at the transcriptional level. PMA induced a program of coordinated transcription of all four genes involved in the biosynthesis of Ia molecules. A spontaneous Ia‐positive variant pre‐B cell line was derived from an Ia‐negative parental cell line. This variant was highly sensitive to the toxic effects of PMA, and highly responsive to the Ia‐inductive effects of phorbol ester. Our findings suggest that in pre‐B cells the appearance of Ia molecules and the regulation of their expression are controlled, at least partially, by variations in the activity of protein kinase C, which is the cellular receptor for phorbol esters.
Functional interleukin 2 receptors on B cells lacking Tac antigens
Authors: Tanaka Toshio , Saiki Osamu , Doi Satoru , Hatakeyama Masanori , Doi Takeshi , Kono Takeshi , Mori Hisashi , Fujii Masahiro , Sugamura Kazuo , Negoro Shigeru , Taniguchi Tadatsugu , Kishimoto Susumu 
Published: March 2007

AbstractHuman B lymphoblastoid line, SKW 6‐4, cells were induced to IgM‐secreting cells by high concentrations of interleukin 2 (IL2). These cells were found to be unreactive with anti‐Tac antibody and did not express mRNA detectable for Tac antigen. In Scatchard plot analysis, low‐affinity IL 2‐binding sites were found on SKW 6‐4 cells. Moreover, analysis of the IL2‐binding molecules revealed ones (molecular weight 70000 and 75000) distinct from Tac antigen. It is conceivable that IL2 exerts its effect through its interaction with these novel IL2‐binding molecules in SKW 6‐4 cells.
A common idiotope on T cell receptors and antibodies expressed in the absence of network selection
Authors: Martinez‐A. Carlos , Pereira Pablo , De La Hera Antõnio , Toribio Marisa , Marcos Miguel R. A. , Marquez Carlos , Coutinho Antõnio 
Published: March 2007

AbstractThe monoclonal antibody F6(51), directed to an idiotope of MOPC 460‐like anti‐1,4,6‐trinitrophenl (TNP) antibodies produced in IgHa mouse strains, identifies in helper T cells from C57BL/6 (IgHb) mice with (4‐hydroxy‐3‐nitrophenyl)acetyl (NP)‐self specificity, a clonotypic determinant functionally and biochemically associated with the specific T cell receptor. The expression of this antibody‐related T cell clonotype in C57BL/6 mice, although “recurrent”, is independent of network selection, as shown by its presence in B mice suppressed from birth with anti‐μ antibodies, and in IgH‐congenic mouse strains. These results indicate aleatory cross‐reactivity between T cell receptors and antibodies and command caution in network interpretations for “idiotype sharing”.
Biological properties of suppressive E‐receptor factor on lymphokine function
Authors: Oh Se‐Kyung , Leung Mun‐Fai , Knee Treyce , Williams John M. 
Published: March 2007

AbstractA potent immunosuppressive factor isolated from malignant ascites fluids showed serological cross‐reactivity with the E‐receptor of human peripheral blood T lymphocytes. Thus, this factor was named suppressive E‐receptor (SER) factor. In this study, we examined the effect of this immunosuppressor, SER, on lymphokine functions of human mononuclear cells participating in polyclonal T cell activation.SER is active at nanomolar concentrations in vitro and the inhibitory effect of SER was most pronounced when added at the initiation of stimulation with phytohemag‐glutinin or anti‐T3 antibody. Concomitant with the inhibition on PHA‐induced DNA synthesis, lymphocytes that were treated with SER failed to progress beyond G1 phase of cell cycle. These growth‐arrested cells did expire after 7 days of culture in vitro. This anti‐proliferative effect of SER was more easily demonstrated with normal lymphoid cells in culture than transformed cells or fibroblast cells. SER effectively interfered with the lympho‐proliferative properties of interleukin 2 (IL2) on human peripheral blood mononuclear cells and an IL2‐dependent murine cytotoxic T cell line. However, excess quantities of exogenous IL2, especially when added in conjunction with IL1, were able to partially overcome the ability of SER to inhibit T cell proliferation.In contrast to the inhibition on DNA synthesis of human lymphoblasts, expression of IL2 receptor was only minimally inhibited by SER during the first 24 h of culture (24% inhibition at 12 h and 34% inhibition at 24 h) but it was followed by full expression of IL2 receptor by 48 h. Thus, SER merely reduced the rate of expression of IL2 receptor and was not able to inhibit the transcription of new message from activated T lymphocytes. Taken together, these studies indicate that SER acts as a noncytolytic anti‐proliferative factor on immune responses that are mediated by T cells. SER appears to act on a relatively late event during T cell activation, perhaps on some portion of the DNA replication pathway.