ISSN:0014-2980    

DOI:10.1002/eji.1830060102

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe expression of membrane immunoglobulin (mIg) was examined in three cloned MPC11‐derived mouse myelom a cell lines. Membrane immunofluorescence studies demonstrated that IgG2bproducer cells (P1) had complete IgG molecules, L‐chain producer (L1) had only L‐chain determinants and nonproducer (NP2) did not have any Ig determinants on the cell surface.An Ig receptor, with characteristics different from B lymphocyte Fc receptor, has been found to be present on secreting cells (P1or L1), but not on the NP2cell variant.The data reported in the present paper indicate that the expression of mIg and of the Ig receptor molecule is clearly correlated with the process of secretion. In the light of previous data reported on Ig secretion, a model is proposed which correlates the process of secretion with the expression not only of mIg, but also of the receptor f

ISSN:0014-2980    

DOI:10.1002/eji.1830060103

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractWe have studied a secondary IgG anti‐dinitrophenyl response in dissociated mouse spleen cell cultures which is comparable in magnitude to the responses detected after adoptive transfer. The data indicate that the responsive precursor cell is not a recirculating memory cell but is an intermediate B cell type which appearsin vivoafter antigen challenge of primed mice. Both antigen and T helper cells are required forin vitrostimulation of the intermediate cell type into the division and maturation steps leading to IgG antibody secretion. The buoyant density of precursor cells has been analyzed by bovine serum albumin density gradient centrifugation, and is consistent with their recent origin by division from memory cell

ISSN:0014-2980    

DOI:10.1002/eji.1830060104

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractMurine cytotoxic T lymphocytes (CTL) were induced in “one‐way” mixed lymphocyte cultures and their physical characteristics investigated by velocity sedimentation at 1 × g. Thein vitrodifferentiation of progenitors of CTL into primary and secondary CTL was paralleled by characteristic changes in the size of the responder cells. Fractionated cells enriched for primary blast CTL reverted into clonally restricted “nonlytic” secondary T lymphocytes. Upon antigenic reexposure, these lymphocytes differentiated into secondary CTL within 18–32 h. This took place in the absence of cell proliferation and could be triggered by UV light irradiated allogeneic stimulator cells. It is suggested that the different characteristics for the induction of either a primary or secondary cytotoxic T cell response reflect qualitative differences between unprimed T cells and memory T

ISSN:0014-2980    

DOI:10.1002/eji.1830060105

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe expression of human β2‐microglobulin was detected on human spermatozoa from 7 donors using a cytotoxicity assay and indirect immunofluorescence. Inhibition experiments using purified β2‐microglobulin demonstrated the specificities of these reactions. We were able to localize β2‐microglobulin on human spermatozoa on the post‐acrosomal region at a similar location to those described for HL‐A antigen and for early embryonic antigen +t12, but also at the end of the intermediary piece and the beginning

ISSN:0014-2980    

DOI:10.1002/eji.1830060106

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractRosette‐forming cells (RFC) from the peripheral blood of sheep red blood cell (SRBC)‐immunized chickens were characterized as B cells which manifest antigen‐binding receptors but no antibody secretion. Lymphocytes were pretreated at 0 °C with anti‐Ig serum, washed, incubated further at various temperatures and harvested for the rosette‐forming cells (RFC) assay. Anti‐Ig treatment blocked all RFC formation and providing that the cells were maintained at less than 10 °C regeneration did not occur up to 6 h. Complete recovery of RFC formation occurred within 10 min at 37 °C following treatment with low but not with high concentrations of anti‐Ig serum. However, recovery from inhibition by high‐dose anti‐Ig treatment was achieved by including chicken IgG in the incubation medium. The recovery of receptors was reduced following “sandwich” treatment of lymphocytes. When cells were treated with anti‐Ig antibody, washed and exposed to various drug inhibitors of “capping” the regeneration of RFC was prevented; in contrast, inhibitors of protein synthesis were ineffective. The results were interpreted in terms of dissociation of anti‐Ig antibodies from the Ig receptor at an early stage of the ligand‐induc

ISSN:0014-2980    

DOI:10.1002/eji.1830060107

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractWe investigated in detail the cation requirements of two different systems of mouse cell‐mediated cytolysisin vitro, at their recognition, post‐recognition hit and target cell disintegration stages. In T cell‐mediated cytolysis, respectively Mg++or Ca++, Ca++, and no cations, were required. In non‐T cell‐mediated hemolysis, respectively no cations, Mg++, and no cations, were required. Two main conclusions can be drawn. First, the cation requirements are different from one system to the other especially at the post‐recognition hit stage, which strongly suggests the existence of differences between both systems as to the actual mechanism of lysis. Second, the cation requirements are different within each system from one step to another. This formed the basis of a step‐by‐step analysis of the lytic process, leading to the characterization of a cation pulse method for the experimental isolation and further study of the post‐recognition hit stage of cell

ISSN:0014-2980    

DOI:10.1002/eji.1830060108

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe F(ab′)2fraction of an anti‐tumor IgG alloantiserum induced passive enhancement of tumor allografts in inbred mice about as well as did intact IgG;i.e.apparently the Fc fragment is not required for suppressing cellular immunity. Passive F(ab′)2, however, was somewhat less efficient than intact IgG or whole alloantiserum in depressing the allohemagglutinin response. The latter finding is in accord with previous observations on the relative inefficiency of F(ab′)2in feedback inhibition of the humoral response of mice to a hetero

ISSN:0014-2980    

DOI:10.1002/eji.1830060109

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractSelective breeding for the character “agglutinin production to heterologous erythrocytes” was performed on random‐bred populations of albino mice. Two types of selection were carried out: Selection I: the first 6 generations were immunized with sheep erythrocytes (SE), then SE and pigeon erythrocytes (PE) were alternated at each generation to avoid the interference of maternal antibody. Selection II: all generations were immunized with SE 60–70 days after weaning in order to eliminate the maternal antibody. Both were selected for the character agglutinin titer 14 days after immunization using an optimal dose of erythrocytes.Selection I.The mean response to SE of the foundation population was 7.36 ± 1.60. The selection limit was attained between the 15th and the 20th generation. The F20−F30were considered as homozygous for the character investigated. The mean SE agglutinin titers were 9.15 (1/2820) in the high responder line and 2 (1/20) in the low responder line. This corresponds to 140‐fold interline difference in agglutinin titers. SE agglutinins determined in F1hybrids, F2hybrids and backcrosses obtained from F23− F29demonstrated incomplete dominance of high responsiveness (23–29%).The inbreeding coefficient produced by close colony breeding was 0.55 in high and 0.71 in low responders at the 20th generation when both lines were homozygous with respect to agglutinin synthesis.Selection II.The mean response of the foundation population to SE was 7.79 ± 1.56. The selection limit was attained in F14−F17generations that were considered homozygous for the character investigated. The mean SE agglutinin titer was 9.2 (1/2900) in high responders and 2.8 (1/35) in low responders, which is an 83‐fold interline difference in agglutinin titers. The results of both selections indicate that the character agglutinin synthesis is subject to polygenic regulation. The heritability (h2) of this character was estimated to be between 0.18 and 0.36 (range between the extreme values of Selections I and II).The attempt to evaluate approximately the number of “loci” is compatible with the hypothesis that a group of about 10 loci regulates the quantitative antibody response. The sources of errors of this evaluation and the significance of the

ISSN:0014-2980    

DOI:10.1002/eji.1830060110

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractHuman lymphocytes obtained from tonsils and peripheral blood were found to bind human fluid phase C3b, obtained by trypsin treatment. This binding was detected by indirect immunofluorescence (IIF) using specific anti‐C3 antisera. Lymphocytes isolated from thymus tissue scored low percentages in IIF, indicating that the main population of thymus‐derived lymphocytes are T cells.The distribution pattern of C3b‐binding cells was compared with that of cells forming rosettes with sheep erythrocytes coated with antibody and complement (EAC) and with sheep erythrocytes (E) only, as well as with that of Ig‐ bearing lymphocytes, as detected by direct immunofluorescence. It appeared that the distribution pattern of lymphocytes which can bind fluid phase C3b is similar to that of EAC rosette‐forming and of Ig‐bearing lymphocytes. Pre‐ incubation of the lymphocytes with C3b and pretreatment of the cells with trypsin decreased the capacity to form rosettes and to bind C3b to their sur‐ face. Human monocytes, granulocytes and erythrocytes did not bind fluid phase C3b, as judged by IIF. Therefore, the selective binding of fluid phase C3b to lymphocytes provides a specific method for the detection of complement‐reactive lymphocytes in lymphoid

ISSN:0014-2980    

DOI:10.1002/eji.1830060111

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY