摘要:

AbstractByin vitromutagenesis of mastocytoma P815, it is possible to obtain tumor cell variants that are rejected by syngeneic mice (tum−). Most of these variants carry new individual antigens and stimulate a specific cytolytic T cell (CTL) response in mixed leukocyte tumor cell culture (MLTC). The H‐2 associativity of this response was examined for six different variants by measuring the inhibition of cell‐mediated cytolysis by antibodies directed against products of the K or the D end of the H−2dcomplex. The lysis was either not inhibited (variants P91 and PI 16) or inhibited selectively by anti‐Kd(variants P21, P32 and P198) or anti‐Ddantibodies (variant P35). All these tum−variants expressed Kdand Ddantigens as measured by absorption of H‐2 alloantisera.Long‐term CTL clones can be obtained that are specific for individual turn antigens. The pattern of H‐2 associativity obtained with MLTC‐derived CTL against four tum−variants was verified with CTL clones directed against the specific antigens of these variants. Concordant results were observed in all cases. In addition to CTL clones specific for tum−antigens, it is possible to isolate clones against a P815 tumor‐associated antigen found on all P815 tum−variants. For these clones no clear associativity with eit

ISSN:0014-2980    

DOI:10.1002/eji.1830121102

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractFor assessment of the distribution of allodeterminants on I‐A molecules, binding inhibition studies were performed with monoclonal anti‐I‐A antibodies (mAb) in which pairs of labeled and unlabeled mAb were tested for cross‐blocking on spleen cells of H‐2 haplotypes b, d and k. The data suggest that allodeterminants are randomly distributed on the surface of the I‐A molecule. Comparison of mAb with cross‐reactivity for b, d or k haplotypes indicates that the allelic forms of determinants are located in analogous positions on different

ISSN:0014-2980    

DOI:10.1002/eji.1830121103

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractThymocytes contain a small population of light (ϱ = 1.067), large cells with high cytolytic potential against natural killer target as well as against IgG‐ or IgM‐coated erythrocytes and nucleated cells, thus displaying natural killer and antibody‐dependent cellular cytotoxicity functions, but not exhibiting T killer cell capacity.As far as characterized, the cells show T cell characteristics: they are nonadherent, nonphagocytic, surface immunoglobulin‐negative, C3 receptor‐negative, partly Fey receptor‐positive, carry the receptor forHelix pomatiaA agglutinin, and are, at least partly, cortisone‐resistant and Thy‐1‐positive.The implications of this finding with respect to the lineage of natural killer and killer cells and their interdependence will be

ISSN:0014-2980    

DOI:10.1002/eji.1830121105

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractConsiderable heterogeneity was found in bone marrow B cell progenitors as functionally defined, size‐separated populations were analyzed for their density of membrane IgM receptors, their adherence potential to nylon wool fibers and their susceptibility to lipopolysaccharide‐induced differentiation to IgM secretion. The investigation of their cycling status with tritiated thymidine further permitted definition of resting and actively proliferating populations. Heterogeneity was found in the fraction of resting small cells as expected for early B cells progressing through postmitotic maturation. However, the data suggest that part of the pre‐B cell progeny can also mature during a proliferative

ISSN:0014-2980    

DOI:10.1002/eji.1830121104

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractLewis rats primed with myelin basic protein (MBP) in complete Freund's adjuvant develop experimental allergic encephalomyelitis (EAE) and suddenly recover 15 to 17 days later. It was previously found that nondraining lymph node (non‐DLN) cells taken at the time of convalescence and transferred into syngeneic normal animals inhibit the subsequent induction of EAE. In this report, it is shown that a suppressive factor can be extracted from non‐DLN cells which mimics the inhibitory effect of cells when injected into the recipients. Non‐DLN cells keep their suppressive activity on the induction of EAE after a culture of 48 h but their supernatant of culture failed to exert any protective effect in vivo. However,invitro both the culture supernatant and the suppressor cells were found to have an inhibitory effect on the proliferative response of immune lymphoid cells to the antigen

ISSN:0014-2980    

DOI:10.1002/eji.1830121106

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractCultured, unprimed spleen cells suppress the generation of cytolytic T lymphocytes when added to mixed lymphocyte culture of cells disparate at minor histocompatibility (H) loci. Cells cultured for 2 to 3 days inhibit cell‐mediated lympholysis specifically in that they suppress only when they carry the same H antigen by which the stimulators activate the responding cells. However, culturing of cells for more than 3 days results also in the generation of nonspecific suppressor cells which inhibit the cell‐mediated lympholysis regardless whether they carry the stimulating antigens. The specific suppressor cells are T lymphocytes of the Lyt‐l+Lyt−2+type. Fresh, uncultured spleen cells, although ineffectivein vitro, can prevent thein vivopriming of minor H‐specific cytotoxic T lymphocyte precursors when injected i.v. into mice incompatible at minor H loci. This suppressive effect of the immunizing inoculum is abolished by irradiation (3300 rds) or by treatment with a monoclonal Thy‐1‐specific antibody and complement. Thus the suppressor T cell demonstrated here is of the “veto” cell type; that is, it probably suppresses minor H‐specific cells when the latter recognize the stimulating antigen on the surface of the sup

ISSN:0014-2980    

DOI:10.1002/eji.1830121107

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractA comparative antigenic analysis was carried out to determine whether cross‐reactivity exists between the major idiotypic responses to (4‐hydroxy‐3‐nitrophenyl)acetyl (NP) in BALB/c and C57BL/6 mice. Extensive cross‐reactivity exists between the NPa(BALB/c) and NPb(C57BL/6) allotype‐linked idiotypic responses to NP. The cross‐reactive determinants of the NPbidiotype are confined to one particular group of NPb‐positive monoclonal antibodies. The extent of cross‐reactivity between this group of C57BL/6 antibodies and idiotype‐positive monoclonal antibodies of BALB/c is so great that they cannot be readily distinguished as NPb‐ or NPa‐positive antibodies with polyclonal anti‐idiotypic reagents. That this cross‐reactivity is not unique to monoclonal antibodies was confirmed by the demonstration of these cross‐reactive determinants in the immune sera of individual BALB/c and C57BL/6 mice. Additionally, evidence was obtained from these experiments and from earlier ones from this laboratory which suggests that the BALB/c idiotypic response to NP‐protein conjugate is more homogeneous than

ISSN:0014-2980    

DOI:10.1002/eji.1830121108

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractStudies with two monoclonal antibodies (DA6.147 and DA6.231) which react, respectively, with isolated human Ia α and β chains are reported. Both antibodies detect epitopes expressed on all DR‐heterozygous and DR‐homozygous cell lines tested (n = 17) and bind to the Epstein‐Barr virus‐negative cell line Ramos. Ia subunit specificity of the antibodies was determined by an adaptation of an electroblot technique which transfers separated la chains from polyacrylamide gels to nitrocellulose paper. In radioimmunobinding assays, peripheral blood B cell‐enriched fractions, phytohemagglutinin‐activated T cells and pokeweed mitogen‐activated cells gave strong reactions with DA6.231 (anti‐Ia β). In contrast, DA6.147 (anti‐Ia α) reacted only weakly, if at all, with peripheral B cells, pokeweed mitogen blasts and activated T cells. However, both antibodies bound to isolated Ia from activated T cells and peripheral B cells after Nonidet‐P40 solubilization of the cells and DA6.147+antigens could be found in the cytoplasm of activated T cells by indirect immunofluorescence techniques. Results of serological inhibition procedures following fractionation of lymphoblastoid cell lysates on monoclonal antibody affinity columns showed that the DA6.147 α chain epitope is carried on only a minor s

ISSN:0014-2980    

DOI:10.1002/eji.1830121109

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractThe kinetics of phytohemagglutinin (PHA)‐stimulated human peripheral blood lymphocytes in the early phases (G0, G1a, G1b) of the first cell cycle have been analyzedin vitroby cytofluorometry and [3H] thymidine incorporation. Cells were detected in the G1aG1band S phases 12‐14, 20‐22 and 24‐26 h after stimulation, respectively. The total number of PHA‐induced G1cells reached a plateau after 32 h of incubation, upon which a second increase followed, 10 h later. The latter increase was considered to be a result of cells initiating their second cell cycle, since it could be abolished by hydroxyurea.By examination of supernatants, interleukin 2 (IL 2) activities could be recovered 6 10 h after PHA stimulation. In contrast, the monokine IL 1 was already detected after 2 h. Both interleukins were present in the culture medium before the major G1a, cell formation took place. The titer of free IL 2 increased to a maximum after 18‐22 h, whereafter a decline was observed. This decline was less pronounced if cultures were treated with hydroxyurea. Finally, among individual donors, the total number of lymphocytes entering the G1phase and the time at which the G1a‐G1btransition took place varied. Lower numbers of G1cells and delayed G1a‐G1btransition coincided with lower IL 2 titers and delayed occurrence of maximal titers in t

ISSN:0014-2980    

DOI:10.1002/eji.1830121110

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractRabbit lymphocytes were analyzed by flow microfluorometry, using anti‐T cell and anti‐Ig reagents. Rabbit T cells and cells expressing surface Ig (B cells) appeared to belong to distinct subpopulations which could be separated on the basis of their selective adherence to nylon wool columns or to anti‐Ig‐coated dishes. Using flow microfluorometry, no evidence was obtained for the expression ofaallotypes (VHframework) on T cells.Separated lymphocyte populations were functionally characterized using anin vitroproliferation assay. B and T cells from rabbit spleen or peripheral blood responded in a differential fashion to B and T cell‐specific mitogens and to anti‐Ig antibodies. Although such T cells did not respond upon stimulation with anti‐Ig antibodies alone, significant proliferation could be induced by simultaneous addition of anti‐Ig and T cell growth factor. In addition, activated T cells, derived from lymph nodes of immunized rabbits, generated a proliferative response upon stimulation with anti‐Ig reagents alone. The above‐mentioned effects on T cells could be obtained using heterologous anti‐Ig antibodies or isologous anti‐allotype antibodies, directed either againstaallotypes (VHframework) or againstballotypes (kappa light chain). Antibodies against the Fc portion of rabbit Ig or against irrelevant allotypic specificities were ineffective in triggering T cells. Fab fragments from anti‐allotype antibodies were equally stimulatory for T cells as compared to intact IgG, indicating that cross‐linking of Ig‐like molecules is not a necessary requirement for anti

ISSN:0014-2980    

DOI:10.1002/eji.1830121111

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY