bluuebunny/crossref_metadata_2025_split huggingface dataset:
Binding and uptake of rabbit IgG complexes by diploid fibroblasts via plasma membrane Fc receptors
Authors: Frey Jürgen , Quentin Hans‐Jürgen , Afting Ernst‐Günter 
Published: February 2007

AbstractThe existence of IgG receptors on the plasma membrane of diploid human fibroblasts is demonstrated. The receptors specifically bind heat‐aggregated rabbit IgG as well as rabbit IgG within antigen‐antibody complexes. Monomeric rabbit IgG were only poor ligands of the receptor. Competition experiments with Fab and Fc fragments of IgG revealed that the receptor specifically recognizes the Fc domain of the IgG molecule. Heat‐aggregated IgG or antigen‐antibody IgG complexes are specifically bound to the receptors, endocytosed and subsequently degraded. The receptors do not seem to be recycled because protein synthesis is a prerequisite for further cycles of endocytosis.
Major histocompatibility complex restriction of tetanus toxoid‐specific human T lymphocyte clones
Authors: Schmitt Christian , Cogné Michel , Agrapart Monique , Ballet Jean‐Jacques 
Published: February 2007

AbstractPeripheral blood mononuclear cells (PBMC) from an HLA DRw6/7 individual were stimulated with tetanus toxoid (TT). T cell blasts were cloned by the limiting dilution technique in the presence of TT and irradiated autologous PBMC (iPBMC). Twelve were propagated under interleukin 2 and restimulated weekly with TT and iPBMC. All proliferated specifically in response to TT or either the α or β chain of the toxin molecule. HLA restriction of specific proliferative responses was analyzed using a panel of HLA‐typed unrelated donors and selected families, and blocking experiments with anti‐HLA class I and class II monoclonal antibodies (mAb). Three types of restriction were observed: (a) autologous restriction; the inhibition observed using anti‐HLA DR mAb as well as family studies performed previously with a similarly restricted clone obtained from the same donor suggest an HLA DRw6‐linked restriction; (b) an HLA DR7 restriction was found for 2 clones, specific for α or β chain; the identical pattern of inhibition obtained with two different mAb belonging to the same cluster suggests that these clones may be restricted by the same (or a very close) epitope of the HLA DR7 molecule; (c) an unusual restriction pattern was found for one clone; PBMC from more than 80% of donors could present TT whatever their degree of HLA compatibility with the autologous donor. Family studies were unable to disclose any restriction with known class II (or class I) antigens. While no inhibition was observed with anti‐DR or ‐DC reagents, a mAb that recognizes class I antigen when associated with β2‐microglobulin did inhibit the proliferation of this clone.
Studies on antibody repertoire: ontogenic development of mitogen‐reactive B cells producing phosphorylcholine‐specific and/or T15‐associated 10/13 idiotopepositive antibodies
Authors: Lévy Martine 
Published: February 2007

AbstractVery high frequencies of phosphorylcholine‐specific and 10/13 idiotope‐positive precursor cells were observed in spleen and liver cells polyclonally stimulated by lipopolysaccharide in BALB/c mice. These frequencies do not show any significant difference at birth, in young and adult mice, suggesting that antibody molecules analyzed arose from a single germ line heavy chain variable region gene segment. The order of magnitude of these frequencies was comparable in germ‐free mice and conventionally reared BALB/c mice. Therefore, external antigenic stimulation does not seem to be involved in the establishment of antibody specificity available repertoire.
Inhibition of proliferative and cytotoxic activities of human T lymphocytes with rabbit antibodies directed against leucoagglutinin‐reactive T cell surface components
Authors: Berzins Toini , Axelsson Bernt , Hammarström Marie‐Louise , Hammarström Sten , Perlmann Peter 
Published: February 2007

AbstractThree rabbit antisera (870, 872 and 873) were raised against leucoagglutinin‐reactive components from the surface of human T cells. The antibodies reacted with two major glycoproteins of 175 kDa and 105 kDa. None of the antibodies triggered peripheral blood lymphocytes or T cells to proliferation when tested under different culture conditions. All antibodies inhibited the proliferative response to concanavalin A or to allogeneic lymphocytes in mixed lymphocyte culture when whole IgG fractions were used. Complete inhibition of cytotoxic activity was obtained in cell‐mediated lympholysis and in natural killer cell cytotoxicity (NK) when fresh peripheral blood lymphocytes were used as effector cells. Weak inhibition was also obtained in NK when mixed lymphocyte culture‐activated effector cells were used. The inhibition was stronger, when NK activity was determined against MOLT4 target cells as compared to K562. Whereas F(ab′)2 fragments of 873 IgG inhibited cytotoxic T lymphocyte activity completely, Fab fragments of 873 IgG neither inhibited proliferation nor cytotoxic T lymphocyte activity, but gave some inhibition of NK against MOLT4 targets. The results indicate that antibodies against these leucoagglutininreactive structures reacted with polypeptides similar to or identical with the human “leukocyte function‐associated antigen‐1” (LFA‐1) considered to be an important mediator of cell‐cell interactions and nonspecific adherence.
Mitogenic capacity of oxidized human B cell lines
Authors: Ren Ee C. , Chan Soh H. 
Published: February 2007

AbstractA combination of neuraminidase and galactose oxidase alters the membrane glycoproteins to generate highly reactive aldehyde groups on galactose moieties. Human B cell lines oxidized in this way were able to induce strong proliferative responses from normal untreated peripheral blood lymphocytes. Oxidized cell lines that stimulate well were also correlated to some extent with their ability to bind responder lymphocytes. The present investigation demonstrates the usefulness of oxidized B cell lines as a novel mitogen for use in the study of lymphocyte activation.
Evaluation of accessory cell heterogeneity. I. Differential accessory cell requirement for T helper cell activation and for T‐B cooperation
Authors: Ramila Gnanadurai , Studer Susanne , Kennedy Marion , Sklenar Ivo , Erb Peter 
Published: February 2007

AbstractSeveral Ia+ tumor cell lines and peritoneal exudate macrophages were tested as accessory cells (AC) for the activation of antigen‐specific T cells and for T‐B cooperation. The macrophages and all the Ia+ tumor lines tested induced the release of lymphokines from T cells in a major histocompatibility complex (MHC)‐restricted fashion and reconstituted the antibody responses of AC‐depleted spleen cells or of purified T and B cells. However, only the normal macrophages but none of the tumor lines induced carrier‐specific T helper (Th) cells which help B cells for specific anti‐hapten antibody responses by linked recognition. For T‐B cooperation accessory cells were also required, but in contrast to Th Cell activation any type of Ia+ AC (e.g. macrophage or tumor line) was effective. Strong MHC‐restriction between the lymphocytes and the AC was seen if antigen‐pulsed AC were added into the AC‐depleted T‐B cooperation cultures. If the AC and antigen were concomitantly added to the AC‐depleted T‐B cultures, MHC‐restriction was less obvious. Concanavalin A supernatant reconstituted the response of AC‐depleted T‐B cultures provided antigen‐specific Th cells and the hapten‐carrier conjugate were present. If, however, tumor line‐activated T cells were added instead of macrophage‐induced Th cells, no cooperation with B cells took place even in the presence of Con A supernatant. The results obtained demonstrate a differential AC requirement for the induction of Th cells depending on the differentiation stage of the Th cells.
Investigation of early T cell activation: Analysis of the effect of specific antigen, interleukin 2 and monoclonal antibodies on intracellular free calcium concentration
Authors: O'Flynn Kieran , Zanders Edward D. , Lamb Jonathan R. , Beverley Peter C. L. , Wallace Diana L. , Tatham Peter E. R. , Tax Wil J. M. , Linch David C. 
Published: February 2007

AbstractThe three mitogenic anti‐T3 antibodies, UCHT1, anti‐Leu‐4 and WT‐32, all produce a rapid increase in T cell intracellular Ca2+ ([Ca2+]j) in all individuals, as measured by quin2 tetra‐acetoxymethyl ester fluorescence. This indicates that the lack of responsiveness of approximately 30% of individuals to UCHT1 in proliferation assays is not due to failure of the antibody to elicit Ca2+ mobilization and that a rise in [Ca2+]j is per se not adequate to induce cell division. Another mitogenic antibody, WT‐31, which is directed against the constant portion of the T cell receptor, did not, however, produce a rapid calcium rise in peripheral blood T cells. The clone HA1.7 gave a similar Ca2+response to UCHT1. WT‐31 did not induce a rise in [Ca2+]j, nor did the specific antigen to which the clone responded. Accessory cells may be required to induce Ca2+mobilization with these ligands. There was no response to IL2, or an antibody (anti‐ Tac) to the IL2 receptor. In contrast to peripheral blood T cells treatment of HA1.7 with WT‐31 led to an enhancement of the calcium response to subsequent UCHT1 addition. Furthermore, cross‐linking of WT‐31 on the surface of HA1.7 cells did produce a small rise in [Ca2+]j. The IL2‐independent malignant T cell line, HUT78, exhibited a calcium response to both UCHT1 and WT‐32. Both of these responses occurred without cross‐linking.The T cell receptor is closely associated with cell‐surface proteins, including the T3 antigen and these studies confirm the importance of the T3 antigen in T cell activa‐ tion. They also suggest that the relationship between the T cell receptor and the T3 antigen may vary in T cells in different proliferative states.
DNA ligases as markers of lymphoid cell maturation and heterogeneity in the chicken
Authors: David Jean‐Claude , Fedecka‐Bruner Barbara , Vaigot Pierre 
Published: February 2007

AbstractThe activities of 8 S and 6 S DNA ligases have been studied in the chicken lymphoid cells of blood, spleen and bursa of Fabricius at different stages of development, from late embryonic life to about 3 months after hatching. These cells have been sorted with the fluorescence‐activated cell sorter FACS Il on the basis of size and T or B antigenicity (immunofluorescence). The light 6S DNA ligase has been previously demonstrated to be associated to a late stage of differentiation of thymocytes. In the bursa, a unique form of 8 S DNA ligase is found during the whole period of observation. This form of enzyme remains in the B cells of the spleen until 3 weeks after hatching, but is never present in the blood B cells. As far as T cells are concerned, the light DNA ligase is present in the blood from 18‐day embryonic life on. In the spleen T cells, on the contrary, this enzyme appears only 3 weeks after hatching. Before this stage, splenic T cells are devoid of any form of DNA ligase activity. These findings show biochemical differences in T and B lymphocytes colonizing the periphery, blood and spleen, and suggest, at least for the T cells at early stages, a heterogeneity in the degree of differentiation.
Antigen‐specific cytotoxic T cell and antigen‐specific proliferating T cell clones can be induced to cytolytic activity by monoclonal antibodies against T3
Authors: Spits Hergen , Yssel Hans , Leeuwenberg Jet , De Vries Jan E. 
Published: February 2007

AbstractT3 is a human differentiation antigen expressed exclusively on mature T cells. In this study it is shown that anti‐T3 monoclonal antibodies, in addition to their capacity to induce T cells to proliferate, are able to induce antigen‐specific cytotoxic T lymphocyte clones to mediate antigen nonspecific cytotoxic activity. It is furthermore shown that anti‐T3 reagents are able to trigger lytic activity in T cell clones characterized as noncytotoxic antigen‐specific proliferating T cells. The data presented indicate that perturbation of T3 can trigger the lytic machinery in cytolytic as well as noncytolytic T cell clones.
Chromosome mapping of cell membrane antigens expressed on activated B cells
Authors: Katz Fay E. , Parkar Mohamed , Stanley Karina , Murray Lesley J. , Clark Edward A. , Greaves Melvyn F. 
Published: February 2007

AbstractHybrids formed by fusion of either human acute lymphoblastic or chronic lymphocy‐tic leukemia cells and the mouse myeloma P3.X63.Ag81653 have been used to show that the expression of two cell surface antigens, Bp37 and p76, associated with B cell activation and detected by the monoclonal antibodies BB1 and BB2, respectively, segregate with human chromosomes 12 and 19, respectively. Another antigen expressed on activated B cells (p24) also maps to chromosome 12 (Katz et al., Eur. J. Immunol. 1984.13:1008) which is of interest in the light of the frequent involvement of this chromosome in certain B cell leukemias and lymphomas.
Induction of immunoglobulin synthesis by interleukin 2 is T4+/T8− cell dependent. A role for interleukin 2 in the pokeweed mitogen‐driven system
Authors: Miedema Frank , Van Oostveen Johan W. , Sauerwein Robert W. , Terpstra Fokke G. , Aarden Lucien A. , Melief Cornelis J. M. 
Published: February 2007

AbstractThe role of interleukin 2 (IL 2) in the induction of human B cell differentiation in vitro was studied. IL2 was unable to induce immunoglobulin (Ig) production in non‐T cells either in the presence or absence of pokeweed mitogen (PWM). However, IL2 alone could induce Ig production in non‐T cells when irradiated T cells were present. Similar to the PWM‐driven system helper activity was delivered by T4+ but not T8+ cells. Apparently, IL2 acts on T4+ cells and induces these cells to deliver the actual helper signal(s) for Ig production by B cells. Whereas in the PWM‐driven system only T8+ cells suppress Ig synthesis, ILZdriven Ig synthesis was suppressed by both T4+ and T8+ cells added to a mixture of non‐T cells and irradiated T4+ cells. This suppressor activity could be abrogated by irradiation. PWM was shown to induce IL2 production in both T4+ and T8+ cells. Moreover, PWM‐induced Ig synthesis, like IL2‐induced Ig synthesis, could be totally abrogated by a monoclonal antibody against the human IL2 receptor (anti‐Tac). These findings, coupled to the innate Ig‐inducing capacity of IL 2, indicate a role for IL 2 in the PWM‐driven system. The mechanism of suppression in both the PWM‐ and the IL 2‐driven systems was not shortage of IL 2 in the culture due to consumption or inhibition of production of IL 2. Moreover, the T8+ cells produced IL2, despite their failure to help Ig synthesis. Helper T cell activity can thus be divided into two distinct activities: (a) IL2 production and (b) the ability to deliver the actual helper signal such as helper factors for B cell differentiation. This insight allows a better evaluation of the immunoregulatory activities of T cell subsets in Gealth and disease.
Evaluation of accessory cell heterogeneity. II. Failure of dendritic cells to activate antigen‐specific T helper cells to soluble antigens
Authors: Ramila Gnanadurai , Smenar Ivo , Kennedy Marion , Sunshine Geoffrey H. , Erb Peter 
Published: February 2007

AbstractThe activation of antigen‐specific T cells requires Ia+, antigen‐presenting accessory cells (AC). Dendritic cells (DC) and macrophages (Mϕ) isolated from spleen and peritoneal exudate were tested as AC for the activation of T helper cells and the induction of T cell proliferation. The cell separations to obtain DC and splenic Mϕ were performed by discontinuous bovine serum albumin gradients, adherence on petri dishes and rosetting with opsonized sheep erythrocytes. DC as well as the Mϕ were able to induce antigen‐specific T cell proliferation, but only the Mϕ and not the DC activated antigen‐specific T helper cells which help B cells for antibody production to soluble antigens. Keyhole limpet hemocyanin‐specific T cells repeatedly stimulated with DC and antigen also did not express helper activity. The failure of DC to induce T helper cells was not due to the activation of a suppressor pathway. Thus, dendritic cells, although very efficient as AC in the induction of various T cell functions, are not able to activate T helper cells required for carrier‐specific T‐B cooperation and therefore cannot be the sole accessory cells. Based on these results and on previous data using Ia+ tumor cell line as AC, we confirm the existence of functional AC heterogeneity.
Murine intestinal intraepithelial lymphocytes. I. Relationship of a novel Thy‐1−, Lyt‐1−, Lyt‐2+, granulated subpopulation to natural killer cells and mast cells
Authors: Petit Agnes , Erst Peter B. , Befus A. Dean , Clark David A. , Rosenthal Ken L. , Ishizaka Teruko , Bienenstock John 
Published: February 2007

AbstractHighly purified populations of intraepithelial lymphocytes (IEL) were obtained from the murine small intestine. We found that 84% of IEL expressed Lyt‐2 and that 45‐55% possessed the unique phenotype, Thy‐1−, Lyt‐1‐, Lyt‐2+. Sixty percent of IEL had granules in their cytoplasm and thus resembled the large granulated lymphocytes associated with natural killer (NK) activity. However, less than 15% of IEL had NK activity in a 6‐h assay. This activity resided in a subpopulation of Lyt‐2‐ lymphocytes, leaving a large population of Thy‐1−, Lyt‐1−, Lyt‐2+ granulated cells (45‐55% of IEL) with unknown function. Sensitive radioenzymic assays for histamine showed that IEL from healthy CBA mice do not contain this amine. IgE‐binding assays revealed that IEL, unlike mast cells, do not carry high‐affinity receptors for IgE. Thus, only a small percentage of granulated IEL (< 15%) possess NK activity, whereas 45‐55% of IEL have granules, lack typical characteristics of mast cells, express the unique antigenic phenotype, Thy‐1−, Lyt‐1−, Lyt‐2+ and have unknown function.
Mott cells are plasma cells defective in immunoglobulin secretion
Authors: Alanen Anna , Pira Ulla , Lassila Olli , Roth Jürgen , Franklin Richard M. 
Published: February 2007

AbstractPlasma cells containing intracellular inclusions of immunoglobulin (Russell bodies) are known as Mott cells, and are found in large numbers in lymphoid organs in autoimmune mice. Hybridoma technique was used to produce cell lines of this phenotype by fusing spleen cells from a NZB mouse with a nonproducing hybridoma cell line (Sp2/0‐Ag14), allowing us to carry out studies of this cell type at the biochemical level. Ultrastructurally the inclusions were distended cisternae of rough endoplasmic reticulum, suggesting a block in the secretory pathway of the cells. Biosynthetic labeling studies confirmed that these cell lines have either a complete or partial block of secretion of immunoglobulin, possibly due to an abnormal light chain.
Accessory function of human leukemic cell lines: properties of B and B‐K562 hybrid cell lines
Authors: Wakasugi Hiro , Dokhelar Marie C. , Garson Dominique , Harel‐Bellan Annick , Fradelizi Didier , Tursz Thomas 
Published: February 2007

AbstractThe accessory function (AF) of various B cell lines has been investigated by studying their ability to replace monocytes inducing the proliferation of highly purified T lymphocytes in the presence of phytohemagglutinin. AF could be exerted by B cells from different origin, including Epstein‐Barr virus (EBV) transformed lymphoblas‐toid cell lines (LCL), Burkitt's lymphoma (BL)‐derived lines, either EBV‐positive or not, pre‐B and B leukemias and lymphomas. The EBV‐converted BJAB‐B95 BL cells could exert an AF as efficient as BJAB cells, their EBV‐negative counterparts, which demonstrates that EBV itself does not play any role in this function. The HLA‐DR antigen‐negative BL‐K562 hybrids PUTKO and DUTKO, T51.4.1.6 cells which derived from an HLA‐DR‐negative variant of the T51 LCL and 721.84.5 cells from a mutagenically dissected HLA‐DR‐negative clone of the 721 LCL, also exerted very efficient AF. 721 LCL, PUTKO and DUTKO hybrids could produce interleukin 1 activity when triggered with 12‐0‐tetradecanoyl‐phorbol 13‐acetate (TPA). Furthermore, addition of anti‐DR monoclonal antibodies which blocked completely the AF of the B cell lines in mixed lymphocyte‐tumor cell reaction did not affect the mitogen‐triggered AF exerted by the same B cell lines. The induction of cellular differentiation with TPA markedly reduced the AF exerted by all B cell lines studied as well as by the hybrid cells DUTKO. By contrast, the PUTKO hybrid was unsensitive to sodium butyrate and TPA treatments, which were unable to abrogate its AF. Taken together, these data indicate that the AF in mitogen‐induced T lymphocyte responses is dependent upon some precise maturational stages of accessory cells and HLA‐DR antigen expression is not required for AF in mitogen‐induced proliferation assays.
Direct demonstration that the monoclonal antibody AMT‐13 and interleukin 2 bind to the same molecule
Authors: Osawa Hisao , Diamantstein Tibor 
Published: February 2007

Abstract125I‐labeled surface molecules from mouse T lymphoblasts were fractionated by affinity supports coupled with recombinant interleukin 2 (IL2) and the monoclonal anti‐ body (mAb) AMT‐13. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) analysis demonstrated that two molecules of ∼ 55 kDa and of ∼ 180 kDa were bound in both cases. Sequential precipitation and SDS‐PAGE analysis of the precipitated molecules revealed that only the ∼ 55‐kDa molecule eluted from AMT‐13 mAb support was rebound to IL2 affinity support. In addition, IL2 inhibited specifically the binding of 125I‐labeled AMT‐13 mAb to T lymphoblasts. Thus the results directly demonstrate that the a ∼ 55‐kDa cell surface molecule repre‐ sents the IL2binding protein and that the mAb AMT‐13 reacts with this molecule.
Biochemical events initiated by exposure of human T lymphocyte clones to immunogenic and tolerogenic concentrations of antigen
Authors: Zanders Edward D. , Feldmann Marc , Lamb Jonathan R. 
Published: February 2007

AbstractInterleukin 2‐dependent helper T cells, cloned from human peripheral blood lymphocytes activated with strain A influenza virus hemagglutinin, proliferate in response to a 24‐residue synthetic peptide (p20) of hemagglutinin, but become unresponsive to a subsequent immunogenic challenge when pretreated with a high concentration of p20. This phenomenon is associated with a loss of the T3 antigen complex, presumably in association with the T cell receptor. We have examined this phenomenon in more detail and show that in addition to changes in the expression of T3 molecules on the cell surface, high doses of p20 cause changes in the expression of certain biosyntheti‐ cally and surface‐labeled proteins, although total DNA and protein synthesis was unaltered. Thus, by examining these biochemical phenomena we can begin to define some of the processes which occur during antigen activation of human T lymphocytes at the clonal level.
Analysis of human T lymphocyte activation in a T cell tumor model system
Authors: Landegren Ulf , Andersson Jan , Wigzell Hans 
Published: February 2007

AbstractThe human T leukemia line Jurkat maintains functional characteristics of normal T cells in responding to inducing stimuli by the release of interleukin 2 (IL2). Presence of a phorbol ester during stimulation eliminated the requirement for specialized accessory cells in the response to cell mitogenic agents such as the lectin con‐canavalin A or treatment with neuraminidase and galactose oxidase. Antibodies directed against the T cell receptor‐associated antigen T3 served as efficient stimuli, especially if aided by agents that cross‐link immunoglobulin, indicating that a triggering signal is received by a T cell via aggregation of its antigen receptor complex. A Burkitt lymphoma cell line, Raji, was found to selectively trigger Jurkat cells, suggesting the ability of those cells to respond to certain foreign stimuli. The Jurkat cell line has been instrumental in the purification of IL2 and cloning of the corresponding gene. Our data suggest it can also serve as a useful model for induction of T cell responses.