摘要:

AbstractTwo monoclonal antibodies (H25 and H366) raised against the cultured T lymphoid cell line HSB‐2 were shown to define a subset of peripheral mononuclear cells with natural killer and killer cell activity. The two antibodies show similar tissue distributions. Radioimmune trace binding assay shows that H25 and H366 react with all T cell lines tested and with the monocyte line U937, but weakly or not at all with cell lines of B, myeloid or erythroid origin. Both antibodies react with about 10% of E rosetteforming cells and a proportion of nonrosetting lymphocytes and monocytes. They do not react with B lymphocytes, granulocytes, red cells or platelets. A proportion of thymocytes and low numbers of tonsil and spleen mononuclear cells are positive. H25+and H366+lymphocytes are medium‐sized cells with abundant granular cytoplasm, and most carry Fc receptors for IgG. H25 and H366 immunoprecipitate two polypeptide chains of 96 and 53kDa from surface‐labeled HSB‐

ISSN:0014-2980    

DOI:10.1002/eji.1830130702

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractSplenic B cells from a variety of mouse strains could be depleted of accessory cells by removal of large cells through velocity sedimentation, followed by adherence to plastic and by passage over Sephadex G‐10. Such accessory cell removal abolished the reactivity of the splenic B cells to the mitogen lipopolysaccharide (LPS), as measured by their capacity to polyclonally proliferate and mature to IgM‐secreting cells. Accessory cells from different sources, such as peritoneal exudate cells, irradiated spleen cells, cells of the macrophage line P388 D1 and macrophages from a single colony grown from bone marrow precursors in semi‐solid media in the presence of colony‐stimulating factor all reconstituted LPS reactivity of the accessory cell‐depleted B cells. Limiting dilutions of the cells of a single macrophage colony indicated that as little as 30 to 1000 macrophages can reconstitute the polyclonal response of 3 × 104B cells to LPS. Not only activated macrophages, but also activated long‐term helper T cell lines and T cell hybridomas, produced supernatant factors which could also restore responsiveness of depleted B

ISSN:0014-2980    

DOI:10.1002/eji.1830130703

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractOur previous work using rabbit antibodies to the variable region of MOPC315 myeloma heavy chain (VH) has indicated the existence of framework determinant(s) common to many murine heavy chains. Here we report the characterization of anti‐VHmonoclonal antibodies (mAb) prepared in an attempt to elucidate the nature of the common VHdeterminant. We immunized AKR/J mice with a purified VH315 fragment and generated somatic cell hybrids by the fusion of the immune AKR/J splenocytes with the NS1 myeloma cells. Thirty‐seven common anti‐VHand 57 subgroup VHI‐specific hybridomas have been established and characterized. Whereas the anti‐subgroup mAb seemed to react with a determinant unique to the MOPC315 (mouse VHI) subgroup, all the anti‐VHmAb reacted with myeloma heavy chains of different VHsubgroups, class and allotypes. Antibody competition studies revealed that the VHsubgroup determinants are distinct from the common VHdeterminants and that both were also recognized by the rabbit polyclonal antibodies. The common VHdeterminants were found to be “hidden” determinants on intact immunoglobulin molecules being exposed only on isolated heavy chains. Furthermore, they are sequential determinants since they are preserved on fully denatured heavy chains. The common VHdeterminants are shared by immunoglobulins of a wide range of vertebrates from amphibia to man and thus represent antigenic structures which were highly conserved throu

ISSN:0014-2980    

DOI:10.1002/eji.1830130704

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThymectomy of very youngXenopuslarvae abrogatedin vitroproliferative responses to phytohemagglutinin (PHA) and allogeneic leukocytes. Thymectomized (Txd) frogs, however, still rejected first‐set skin allografts chronically and second‐set grafts (but not third‐party grafts) more rapidly. The specific second‐set rejection reaction by Txd frogs was transferablein vivoto secondary Txd hosts (with major histocompatibility complex identical to the cell donor) by the subcutaneous injection of a mixture of splenic and peripheral blood leukocytes. Spleen cells used in this adoptive transfer experiment (i.e., immune cells) were responsive to allogeneic cells from the original donor strain as well as from unrelated donors in mixed leukocyte culturein vitrobut were still unreactive to PHA. The results are consistent with an extrathymic pathway of alloreactive cell differentiation in this species, although the physiological significance of such a pathway is no

ISSN:0014-2980    

DOI:10.1002/eji.1830130705

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractA monoclonal antibody to trout serum IgM was tested by immunofluorescence analysis with lymphocytes from thymus, spleen and head kidney. By visual examination, the antibody reacted with only a subpopulation of lymphocytes. The mean values ± SE for positive cells were 5.2 ± 2.3% in the thymus, 30.3 ± 7.9% in the spleen and 12.4 ± 3.0% in the head kidney. Flow cytofluorometric analysis revealed evidence of heterogeneity by size among the membrane IgM‐positive cells of the head kidney and spleen. Depletion of head kidney cells positive for surface IgM by an immune affinity adherence technique of panning, using monoclonal anti‐IgM, significantly reduced the mitogenic response to lipopolysaccharide but not to concanavalin A. It is suggested that this information supports the existence of distinct subpopulations of fish lymphocytes that may be homologous in certain respects to mammalian T and B typ

ISSN:0014-2980    

DOI:10.1002/eji.1830130706

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe antigen‐specific T suppressor cell clone HF1 isolated from a CBA/J mouse made tolerant by low doses of bovine serum albumin has suppressive and cytolytic activity. The analysis of the latter gave the following results. Natural killer (NK)‐sensitive YAC‐1 (H‐2a) and RBL‐5 (H‐2b) target cells are lysed whereas other NK targets, like EL4 (H‐2b) or the human K562 cell line are resistant. Cytolytic activity is not antibody mediated. Its inhibition by sugar phosphate or monoclonal antibodies against LFA‐1 antigens is such that HF1 can neither by typed as T killer nor as NK cells. It seems to represent a distinct T

ISSN:0014-2980    

DOI:10.1002/eji.1830130707

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractTo test the hypothesis that γ3is the pivotal isotype for sequential heavy chain switching from μ to each of the γ isotypes, we have compared the effects of anti‐γ3and anti‐μ antibodies on the expression of immunoglobulin isotypes in lipopolysaccharide (LPS)‐stimulated cultures of mouse spleen cells. IgM‐, IgG1‐, IgG2b‐ and IgG2a‐containing plasma cells were enumerated by immunofluorescence and secreted immunoglobulins were measured by radioimmunoassay. Although anti‐γ3and anti‐μ, were equally effective in inhibiting the LPS‐induced differentiation of IgG3plasma cells, anti‐γ3had no effect on the differentiation of IgM, IgG1, IgG2b, or IgG2aplasma cells. These results support a direct mechanism of heavy c

ISSN:0014-2980    

DOI:10.1002/eji.1830130708

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractChicken spleen and peripheral blood lymphocytes were tested for their ability to produce T cell growth factor (interleukin 2, IL2) upon stimulation with phytohemagglutinin or concanavalin A (Con A). Using a qualitative microassay, peak activity was found in 24‐h supernatants of mitogen‐stimulated lymphocytes. These supernatants permitted continuous growth of chicken lymphocytes for several weeks and increased the Con A response of chicken thymocytes. A quantitative probit microassay was developed and used in the further studies when appropriate. Chicken IL2 binds specifically to thymocytes and activated T cells and its action upon T blast cells cannot be blocked by cyclosporin A. The molecular weights of the two biological active peaks found by gel filtration of the native IL 2 preparation were in the range 19500‐21500 and 9000‐11500. A single polypeptide of molecular weight 13000 was found by gel electrophoresis under reducing con

ISSN:0014-2980    

DOI:10.1002/eji.1830130709

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe existence of a molecule in chickens homologous to the secretory component of mammals has long been in dispute. An intravenous injection of [14C]fucose was given to chickens as a marker for newly synthesized glycoproteins and then unlabeled human IgA was injected intravenously half an hour later. It was shown that the human IgA subsequently appeared in the bile of the chickens combined with a [14C]fucose‐labeled molecule; the chicken IgA in these bile samples was similarly labeled. Radiolabeled human secretory IgA was not transported in large amounts across the chicken liverin vivoand neither was purified chicken bile IgA. These results indicate that a molecule exists in chickens which behaves in a manner analogous to mammalian secretory componen

ISSN:0014-2980    

DOI:10.1002/eji.1830130710

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractGenetic variation in the response of chicken lymphocytes to the T cell mitogen concanavalin A (Con A) has previously been studied by assaying tritiated thymidine ([3H]dThd) uptake of cultured cells following mitogen stimulation. Our present results show, firstly, that low [3H]dThd uptake(e.g.in cultures of Con A‐stimulated cells from low responder CB, CC or G‐B1‐lo birds) is correlated with low proliferative activity and with reduced capacity to form Con A‐dependent T cell colonies in semisolid agar. Secondly, in cultures containing mixtures of cells from high and low responder birds, the cells from each partner respond independently to Con A (there is neither suppression of high responder, nor activation of low responder cell proliferation). Finally, Con A‐stimulated cultures of high responder cells respond better to T cell growth factors, as well as producing more growth factor activity, than cultures of low responder cells. These results suggest that the basis for the low responder phenotype is an intrinsic inability of low responder T lymphocytes to respond to Con A by differentiating into growth factor‐sensitive

ISSN:0014-2980    

DOI:10.1002/eji.1830130711

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY