bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vivo suppression of perinatal multispecific B cells results in a distortion of the adult B cell repertoire
Authors: Vakil Meenal , Sauter Helmut , Paige Christopher , Kearney John F. 
Published: February 2007

AbstractThe isolation of multispecific B cell hybridomas with a variety of anti‐idiotype (anti‐ Id) activities from the lymphoid organs of fetal and neonatal B ALB/c mice suggested that the development of the immune system may depend on Id interactions among autologous B cells. In vitro analysis of antibodies secreted by these hybridomas showed extensive sharing of an idiotope defined by the monoclonal antibody FD5–1. Early and timed administration of this antibody during the perinatal period results in a distortion of the phosphorylcholine (PC) and a(l±3)dextran (Dex)‐specific B cell precursor compartment of the developing repertoire and is reflected by a drastic reduction of antibody responses to these antigens when challenged as adults. These observations provide strong evidence for the involvement of the early appearing multispecific B cells in Id interactions that bring about the uniform development of the normal adult B cell repertoire. Interference with these interactions at critical stages of development results in permanent deficiencies in the adult B cell repertoire.
Epstein‐Barr virus‐induced IgE production in limiting dilution cultures of normal human B cells
Authors: Stein Leonard D. , Chan Marcia A. , Hibi Toshifumi , Dosch Hans‐Michael 
Published: February 2007

AbstractThe induction of in vitro IgE production in human B cells from normal, nonatopic donors has been difficult and somewhat controversial. We report that IgE production is consistently observed in limiting dilution cultures of in vitro Epstein‐Barr virus (EBV)‐infected normal human B lymphocytes. The frequency of IgE‐committed, EBV‐responsive cells ranged from 1/810 to 1/10000 B lymphocytes, and it was similar in peripheral (blood, tonsil) and central (bone marrow) tissue sites. Poisson distribution analysis of these limiting dilution cultures suggested that IgE‐committed B cells comprise 0.1–1% of all EBV‐responsive B lymphocytes.
In vivo administration of interleukin 2 stimulates mitosis in thymus and bone marrow
Authors: Gearing Andrew J. H. , Wadhwa Meenu , Perris Alan D. 
Published: February 2007

AbstractWe have used short‐term, high‐density cultures to demonstrate that interleukin 2 (IL 2) in picomolar amounts causes entry of approximately 2% of thymocytes from 3‐ month‐old rats into mitosis. Newborn and fetal animals show a higher response reflecting a greater proportion of cells which have been shown to express IL 2 receptors at this age. In vivo administration of nanogrammes of IL 2 or injection of rats with syngeneic spleen cells which had been stimulated in vitro with concanavalin A to release IL 2 were also shown to increase the proliferation of both thymus and bone marrow cells. This suggests that IL 2, in amounts which could be produced by peripheral lymphoid tissue during immune responses, could act to increase the turn‐over of lymphocytes in bone marrow and thymus.
Does the deletion within T cell receptor β‐chain gene of NZW mice contribute to autoimmunity in (NZB × NZW)F1mice?
Authors: Yanagi Yusuke , Hirose Sachiko , Nagasawa Ryuji , Shirai Toshikazu , Mak Tak W. , Tada Tomio 
Published: February 2007

AbstractTo determine the transacting genetic factors of NZW contributing to the development of autoimmune disease in (NZB ± NZW)F1 (B/WF1) mice, we examined the relationship between the T cell receptor β chain gene deletion and the severity of autoimmune manifestations in 76 B/WF1 ± NZB backcross mice. Very high association between the T cell receptor β chain gene deletion and the development of autoimmune manifestations including the production of IgG anti‐DNA antibodies and circulating retroviral gp70 immune complexes was observed, indicating that a defect in the NZW T cell receptor β chain gene or a locus closely linked to it contributes to the autoantibody formation in B/WF1.
Insulin‐specific T cell help to TNP‐specific B cells requires activation via the antigen T cell receptor
Authors: Rubin Bent , Boned Annie 
Published: February 2007

AbstractIn the present study, the production of large numbers of insulin (Ins)‐specific, H‐2‐ restricted T helper (Th) cell clones is described. Among 148 clones analyzed, 121 clones had Th cell function, and these were divided into 75 Ins‐specific Th cell clones and 52 autoreactive clones. The 148 clones were isolated from Ins‐specific T cell lines produced by in vitro stimulation of T lymphocytes from (b ± d)F1 mice immunized with Ins 7, 14, 32 or 56 days before. The following characteristics were tested with regard to the Th, cell clones: restriction specificity and antigen requirement for optimal help or interleukin 2 (IL2) production. No differences in these characteristics were found among clones originating from day 7, 14, 32 or 56 T cell lines. A preference for H‐2b as restriction element and an antigen concentration of about 0.01 μg trinitrophenylated (TNP)‐Ins/ml for optimal help were general traits. Optimal IL2 release is not yet obtained with 100 ug TNP‐Ins/ml. Thus, the antigen requirement for optimal help and IL 2 release differs by a factor 104 at least.Certain twice‐cloned Th cell lines were tested for IL2 production when stimulated with anti‐Thy‐1 monoclonal antibodies (mAb). All clones analyzed were stimulated by mAb H155 but not with mAb H140 nor with mAb against Lyt‐1, L3T4, LFA‐1 or H‐2K/D molecules. Therefore, we determined whether TNP‐conjugated H155 mAb would mediate Th cell‐B cell collaboration as well as TNP‐Ins. The results with nine different Th cell clones and six different TNP‐conjugated mAb used in a 107‐fold concentration range showed that Th cell clones have to be triggered via the T cell receptor for expression of helper function to B cells.Thus, though IL2 gene activation, synthesis or release apparently can be activated via at least two pathways: (a) T cell receptor or (b) Thy‐1, it seems that activation of the genes responsible for synthesis and release of the helper factors, which ensure antigen‐specific B cell proliferation and differentiation, needs Th cell‐B cell contact mediated via the antigen‐specific T cell receptor.
B cell hyperactivity in systemic lupus erythematosus: selectively enhanced responsiveness to a high molecular weight B cell growth factor
Authors: Delfraissy Jean‐François , Wallon Christine , Vazquez Aimé , Dugas Bernard , Dormont Jean , Galanaud Pierre 
Published: February 2007

AbstractTo characterize B cell hyperactivity in systemic lupus erythematosus (SLE) patients we studied the early events of B cell activation in 14 patients and controls. We measured B cell proliferation induced by three interleukin (IL) preparations (20‐kDa B cell growth factor, BCGF, recombinant IL2 and 50‐kDa BCGF) in the absence and in the presence of an anti‐μ antibody (Ab). SLE B cells exhibited a markedly enhanced proliferative response to the 50‐kDa BCGF in the absence of an anti‐μ Ab, while responding normally in the presence of a first signal. This pattern of hyperactivity was observed in 11 out of 14 patients tested, and was absent in control patients. In contrast, SLE B cells behaved like normal B cells for the response to the other two IL tested, and to the anti‐μ Ab alone. It should be pointed out that SLE B cells responded normally to recombinant IL2 whereas T cells from the same patients exhibited a decreased response to this IL. The selectively enhanced responsiveness of SLE B cells to the 50‐kDa BCGF suggests that the events leading to B cell hyperactivity in this disease affect the early stages of B cell activation.
Immunoglobulin‐bearing B cells reconstitute and maintain the murine Ly‐1 B cell lineage
Authors: Hayakawa Kyoko , Hardy Richard R. , Stall Alan M. , Herzenberg Leonard A. , Herzenberg Leonore A. 
Published: February 2007

AbstractPrevious reconstitution studies in irradiated mice distinguished Ly‐1 B from other B cells. The predominant B cell populations in spleen and lymph node are readily reconstituted from progenitors present in adult bone marrow. Ly‐1 B cells, in contrast, are reconstituted from cells in peritoneum rather than bone marrow. Further studies, presented here, demonstrate that Ly‐1 B populations are reconstituted from peritoneal cells that already express both surface immunoglobulin (IgM) and Ly‐1, that is, Ly‐1 B. Such cells reconstitute and maintain the Ly‐1 B population in irradiated recipients for at least 6 months.
VLA‐3: A novel polypeptide association within the VLA molecular complex: cell distribution and biochemical characterization
Authors: Sánchez‐Madrid Francisco , De Landázuri Manuel O. , Morago Gloria , Cebrián Marta , Acevedo Augustín , Bernabeu Carmelo 
Published: February 2007

AbstractThe family of human T cell activation‐associated proteins, named VLA complex, is formed by the molecular association of cell surface glycoproteins of 210, 165, 130 and 80 kDa. In this report, we describe eight different monoclonal antibodies (HP mAb) specific for the 80‐kDa polypeptide which preferentially associates with the 165‐kDa member. Comparative immunoprecipitation and cell‐binding studies demonstrated that the HP mAb recognize an epitope(s) on the 165/80 kDa subset different from those recognized by other anti‐VLA mAb previously described. Furthermore, cellular and tissue distribution studies by flow cytometry and peroxidase staining showed that the HP reactivity pattern is different from other VLA specificities. The 165/80‐kDa complex defined by HP mAb is present on human thymocytes, peripheral blood lymphocytes as well as on T, B and myelomonocytic cell lines. However, only the 80‐kDa subunit was precipitated by HP mAb from activated T lymphocytes. These results suggest that the association between the 165‐ and 80‐kDa subunits diminishes during the activation process, and that the epitopes recognized by the HP mAb are located on the 80‐kDa protein. The novel polypeptide association of 165/80 kDa has been termed VLA‐3.
The molecular evolution of the immune response: idiotope‐specific suppression indicates that B cells express germ‐line‐encoded V genes prior to antigenic stimulation
Authors: Manser Tim , Gefter Malcolm L. 
Published: February 2007

AbstractAntibodies expressed by the immune B cell population are characterized by variable region amino acid substitutions resulting from somatic nucleotide replacement (somatic mutation). This is not true of antibodies expressed by the “naive” B cell population. It is at present unclear whether this discrepancy is due to the preferential clonal selection of a pre‐existing subpopulation of naive B cells that express variable regions altered via nucleotide replacement, or whether the process of nucleotide replacement occurs only during the antigen‐dependent stages of B cell differentiation. To address this question we have used anti‐idiotypic suppression to functionally delete B cells that express particular variable‐region structures from the antigen‐responsive repertoire. Suppression of the major cross‐reactive idiotype (IdCR) expressed in strain A mice in response to p‐azophenylarsonate (Ars) was induced using the monoclonal anti‐IdCR antibody AD8. The idiotope recognized by AD8 is easily destroyed by alteration of IdCR variable‐region structure via nucleotide replacement. The IdCR anti‐Ars immune repertoire is characterized by antibodies that lack the AD8‐cognate idiotope due to nucleotide replacement. However, complete suppression of the IdCR could reproducibly be achieved by administration of AD8 prior to Ars immunization. This result indicates that all IdCR‐expressing B cells also express the AD8‐cognate idiotope prior to immunization. Thus, somatic nucleotide replacement must occur exclusively during the antigen‐dependent stages of B cell differentiation in this system.
Phenotypic characterization of individual interferon‐γ‐producing cells after OKT3 antibody activation
Authors: Andersson Ulf , Laskay Tamas , Andersson Jan , Kiessling Rolf , Deley Marc 
Published: February 2007

AbstractThis is the first study using a direct approach to determine the phenotype of interferon gamma (IFN‐γ)‐producing cells after polyclonal T cell activation. Blood mononuclear cells (MNC) were cultured and stimulated by OKT3 antibody to produce IFN‐γ. They were then stained with a panel of monoclonal antibodies with specificity for cell surface antigens, fixed and permeabilized in suspension and stained for cytoplasmic IFN‐γ using monoclonal antibodies and indirect immunofluorescence technique. IFN‐γ appeared mainly as a local, polar accumulation in the cytoplasm in a juxtanuclear position, probably identical to the Golgi apparatus. After a culture period of 20 h, 6–11% and 0.2–0.6% of the OKT3‐activated MNC from adults or newborns, respectively, produced IFN‐γ in cultures. Unstimulated cultures contained maximally 0.1% IFN‐γ‐positive MNC. The majority of the IFN‐γ‐producing MNC were T cells and expressed the T11 antigen and receptors for interleukin 2. To our surprise most of these T cells also carried receptors for complement 3bi (OKM1) but did not express class II molecules. Less than 50% displayed T4 or T8 antigens in three out of the four experiments performed. Natural killer cells, as recognized by Leu7 or B73.1 antibodies, contributed only marginally to the IFN‐γ synthesis whereas B cells (OKB7) and monocytes (Leu M3) showed no production of IFN‐γ.
Human immunodeficiency virus gp120 glycoprotein detected by a monoclonal antibody to a synthetic peptide
Authors: Chanh Iran C. , Kennedy Ronald C. , Alderete Benjamin E. , Kanda Patrick , Eichberg Jorg W. , Dreesman Gordon R. 
Published: February 2007

AbstractA chemically synthesized peptide corresponding to the amino acid sequence 503–532 of gp160 of human immunodeficiency virus (HIV) was used to generate monoclonal antibodies reactive with the env glycoprotein gp120. One monoclonal antibody, 120‐1, was isolated that reacted with the peptide and with HIV antigen(s). Western blot analysis showed reactivity with two bands of 120 kDa and 88 kDa. 120‐1 reacted in indirect immunofluorescence with 15–20% of infected human T cell line A3.01 as early as 4 days post in vitro infection, 2–3 days prior to detectable reverse transcriptase activity in supernatant fluids.
Activation of lymphokine genes during stimulation of cloned T cells
Authors: Herold Kevan C. , Lancki David W. , Dunn Daniel E. , Arai Ken‐Ichi , Fitch Frank W. 
Published: February 2007

AbstractTo study the regulation of lymphokine production by T lymphocytes, we have characterized the activation of lymphokine genes in T cells by measuring the levels of lymphokine mRNA in cloned murine T lymphocytes after stimulation. Lymphokine mRNA was not detected in cells taken after seven days of maintenance culture. Following stimulation of T helper lymphocytes L2 and AD9.1 with concanavalin A, lymphokine mRNA appeared, reached peak levels and disappeared over a 43‐h time period. A single stimulation event resulted in the induction of mRNA for interleukin 2 (IL2), IL3 and interferon gamma. Maximal mRNA levels were generally found at 6 h in the T helper lymphocytes, but could occur as late as 18 h. The lymphokine genes were expressed coordinately; however, in these cloned cells, IL2 mRNA levels appeared to be lower than the other two mRNAs. Lymphokine titers in the supernatant fluids paralleled the appearance of mRNA but IL2 titers began to fall after 12 h probably because of utilization of this lymphokine by the activated cells. In the cytolytic T lymphocyte, L3, qualitatively similar kinetics were found after stimulation by lectin or a clonotypic antibody with peak mRNA levels occurring later (18 h) with the antibody. These studies indicate (a) a single stimulating event activates the lymphokine genes of T cells in a coordinate manner; (b) the appearance of the lymphokines in supernatant fluids represents de novo synthesis of these proteins but the levels of lymphokines measured in supernatant fluids reflects both production and utilization rates, and (c) exposure to IL2 at the time of stimulation is not essential for the production of other lymphokines.
2.4G2, a monoclonal antibody to macrophage Fcγ receptors, reacts with murine T cell Fcγ receptors and IgG‐binding factors
Authors: Daëron Marc , Néauport‐Sautès Catherine , Blank Ulrich , Fridman Wolf H. 
Published: February 2007

AbstractIn order to determine whether T cell Fcγ receptors (FcγR) and IgG‐binding factors (IgG‐BF) are structurally related, we searched for common antigens on these molecules. We found that the anti‐macrophage Fcγ1/γ2bR monoclonal antibody 2.4G2 binds to similar determinant(s) on the macrophage‐like J774 cells and on the FcγR+hybridoma T cells T2D4. On the T cell membrane, these determinants are associated with Fcγ1/γ2bR. They are absent on FcγR hybridoma T cells or the FcR− BW5147 thymoma cells. 2.4G2‐reactive molecules were also detected in soluble material either extracted or released in the supernatant of FcγR+ hybridoma T cells. 2.4G2‐reactive molecules released in the supernatant of T2D4 cells could be absorbed on Sepharose beads coupled to rabbit IgG and they were recovered by acid elution. Conversely, Sepharose beads coupled to 2.4G2 retained molecules which had affinity for rabbit IgG, which suppressed an in vitro antibody response and which had the same molecular weight as IgG‐BF. These results indicate that T cell FcγR and IgG‐BF share common epitopes and that 2.4G2 can serve as an anti‐IgG‐BF antibody.
Differences in the recruitment of virgin B cells into antibody responses to thymus‐dependent and thymus‐independent type‐2 antigens
Authors: Lane Peter J. L. , Gray David , Oldfield Susan , MacLennan Ian C. M. 
Published: February 2007

AbstractThe bone marrow of mammals generate large numbers of B cells throughout life. Most of these have a short life span. The subject of this report is to investigate the extent to which newly formed virgin B cells can be activated by thymus‐dependent (TD) and thymus‐independent type 2 (TI‐2) antigens carrying the hapten 2,4‐dinitrophenyl. The experimental approach used chimeras made between congenic rats of different kappa immunoglobulin light chain allotype. Host (xla) rats were depleted of peripheral B cells by whole body irradiation but had B lymphopoietic capacity conserved by shielding the hind limbs. Their peripheral B cell pool was reconstituted by transfer of xlb thoracic duct lymphocytes from donors immunized previously with the TD carrier. This provides test animals where newly produced virgin B cells only express xla but where initially most peripheral B cells are xlb. The TD antigen tested was able to activated both virgin and memory B cells in the period immediately following immunization. However, long‐term antibody production was attributable to repeated activation of memory B cell clones without further virgin B cell recruitment. By contrast, antibody evoked by the TI‐2 antigen initially was almost exclusively due to activation of donor peripheral B cells. However, over a period following TI‐2 immunization there was a progressive increase in the amount of host antibody produced with corresponding decline of the donor component of the response so that the host response was dominant by six weeks. Control experiments were conducted to show that these effects could not be explained by allotype or isotype‐directed suppression. The cellular basis of these differences was investigated further by studying the rate of repopulation of different B cell compartments in these chimeras by newly formed host and mature donor B cells. The results indicate that the onset of host antibody production to the TI‐2 antigen closely correlated with the appearance of host B cells in the marginal zones of the spleen, whereas good TD host anti‐2,4‐dinitrophenyl responses antedated the appearance of host B cells in this compartment. These results are discussed in relation to other data implicating marginal zone B cells in responses to TI‐2 antigens.
Biochemical characterization of a soluble form of the 53‐kDa monocyte surface antigen
Authors: Bažil Vladimír , Hořejší Václav , Baudyš Miroslav , Krištofová Hana , Strominger Jack L. , Kostka Wladimír , Hilgert Ivan 
Published: February 2007

AbstractTwo monoclonal antibodies, MEM‐15 and MEM‐18, were prepared which recognize a monocyte 53‐kDa antigen. A soluble form of this antigen was found in most normal sera and in urine of some nephrotic patients. Milligram amounts of this glycoprotein were isolated by immunoaffinity chromatography from urine and used for quantitative amino acid and carbohydrate analysis and N‐terminal amino acid sequencing. The reactivity of the isolated antigen with several previously described monoclonal antibodies indicates that it is the antigen previously called MY‐4 or MY‐23. A significant homology exists between the sequenced N‐terminal portion of the antigen and sequences found in the kinase‐related transforming protein src and in the precursor of epidermal growth factor.
Use of Vpß.8 genes in splenic Lyt‐2+ cytotoxic lymphocyte precursors reactive to bm1 or bm14 alloantigen in individual C57BL/6 mice
Authors: Reimann Jörg , Bellan Astrid 
Published: February 2007

AbstractThe cytotoxic response of cell sorter‐purified small Lyt‐2+ splenic cytotoxic lymphocyte precursors from 10 individual C57BL/6 mice to mutant class I H‐2Kbm1 or H‐2Dbm14 allodeterminants was analyzed under limiting dilution conditions. The cytotoxic activity of anti‐bm1‐specific or anti‐bml4‐specific cytotoxic T lymphocyte (CTL) populations (selected for a high probability of clonality) was tested against F23 hybridoma cells; F23+ CTL clones lysed F23 hybridoma targets but F23− CTL clones did not. In the C57BL/6 anti‐bml mixed lymphocyte reaction, 36% (range 29–48%) of the generated CTL clones were F23+; in the B6‐anti‐bml4 mixed lymphocyte reaction, 45% (range 34–49%) of the generated CTL clones were F23+. Hence, a large fraction of the anti‐bml‐ or anti‐bm14‐reactive CTL clones from C57BL/6 mice use Vß.8 genes to construct these allospecific T cell receptor phenotypes, but no extensive variation in the use of Vß.8 genes in the construction of allospecific T cell receptor phenotypes of restricted heterogeneity is found in individual mice of the same strain.
Immunochemical analysis of a cell transfected with an HLA‐DR gene reveals a new alloantigenic specificity within HLA‐DRw52
Authors: Tosi Roberto , Tanigaki Nobuyuki , de Préval Claude , Gorski Jack , Mach Bernard 
Published: February 2007

AbstractThe HLA‐DR antigen has been prepared from the surface of a mouse fibroblast cell line transfected with a single HLA‐DR β‐chain gene as well as single HLA‐DR a and invariant chain gene. Since the HLA‐DR β chain gene studied corresponds to the DR βIII locus, the DR serological specificities detected on the transformed cells can be assigned to this locus. The use of the HLA‐DR‐producing mouse cell line has led to the identification of a new serological specificity included within DRw52 and associated with some DR3, some DRw6 and all DR5 haplotypes studied. Most likely this new specificity corresponds to an allelic polymorphism at the DR βIII locus of DRw52 individuals and can serve as a new serological marker for this subset of DR3, DR5 and DRw6 haplotypes.