摘要:

AbstractSome macrophage (MΦ) cell surface structures which bind T cell‐derived factors remain intact after the MΦ are killed by heating at 56°C(but not 72°C) for 45 min. As a result, appropriately killed MΦ (HK MΦ) can act as competitive antagonists for those MΦ functions which are involved in binding and active presentation of T cell derived regulatory signals. By blocking the transmission of these signals with HK MΦ, we have found that the spleens of newborn mice contain considerable numbers of “latent” helper cells whose activity is not ordinarily seen because it is overridden by suppressor mechanisms. Similarities between these neonatal helper cells and a subset of adult T helper “inducer” cells (cell surface phenotype Ly‐1+; Ly‐2−,3−; IJ+; Qa l+), whose activity appears in significant numbers only after im

ISSN:0014-2980    

DOI:10.1002/eji.1830090702

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractIn vitroprepared antigen‐specific helper factors reactive to the synthetic polypeptide antigens poly‐L(Tyr, Glu)‐poly‐DLAla‐ ‐poly‐LLys [(T, G)‐A‐ ‐L] orLGlu60‐La30‐LTyr10(GAT) and bearing Ia determinants were analyzed serologically to determine the nature of the Ia determinants they expressed.I subregion‐specific mouse anti‐Ia antisera were used, and showed that (T, G)‐A–L specific helper factor (HF) contains I‐A subregion‐controlled determinants, whereas GAT‐specific HF carries I‐J subregion‐controlled antigens. This unexpected finding was confirmed in both the H‐2kand H‐2bhaplotypes, using a variety of anti‐I‐J antisera.Rabbit anti‐Ia antisera also reacted with both HF which raised the possibility that the Ia determinants on HF may be carbohydrate in nature. The fact that HF has a low molecular weight and yet contains Ia determinants, antigen‐binding capacity and idi

ISSN:0014-2980    

DOI:10.1002/eji.1830090703

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractThe time course of the rate of labeling of membrane components (phospholipids, glycolipids and glycoproteins) and DNA was followed in concanavalin A‐stimulated CBA/J mouse thymocyte cultures. Two peaks of stimulated biosynthetic activity were noted, the first at the beginning of the cultivation and the second about 25 h later. Both early and late peaks of biosynthesis of membrane components were accompanied by blast transformation and were unimpeded by suppression of DNA synthesis by hydroxyurea.Cortisone‐sensitive and cortisone‐resistant thymocytes were prepared by selective agglutination of the cortisone‐sensitive cells with peanut agglutinin (Reisner et al.Cell. Immunol.1976.25: 129) or cortisone treatment of the animals. Cortisone‐sensitive cells responded early, while the cortisone‐resistant population gave only the late response.The autoradiographic patterns from sodium dodeeyl sulfate polyacrylamide gels of [3H]fucose or [3H]galactose‐labeled glycoproteins from early and late labeling cells, and cortisone‐resistant cells, were compared. Late‐labeling and cortisone‐resistant cells gave indistinguishable patterns, but differed significantly in their patterns from early‐labeling cells.It is concluded that the two peaks of biosynthetic activity during the course of concanavalin A stimulation of thymocytes are caused by two different cell populations which require different times for maximal response and react indepen

ISSN:0014-2980    

DOI:10.1002/eji.1830090704

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractTwo clones of MOPC 315 cells have been selected which synthesize but do not secrete Ig lambda light chains. These clones were analyzed by fusion with a cell line synthesizing and secreting kappa chains. Conditions were established for recovery at high frequency (approximately 10−3) of spontaneously fused, viable hybrid cells. The resulting hybrid cell lines synthesized both kappa and lambda chains but secreted only kappa chains. Hybrid cells produced by fusion of a lambda‐secreting clone of MOPC 315 with the kappa‐secreting cell line were also isolated and shown to synthesize and secrete both kappa and lambda chains. These results suggest that the nonsecretion of lambda chains was not due to a defect in the secretion mechanism of the variant cells. A more likely alternative is that the lambda chains in the variant cell lines were structurally altered to a form which could not be sec

ISSN:0014-2980    

DOI:10.1002/eji.1830090705

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractBy means of blister formation produced by cantharidin, a certain number of human macrophages could be readily obtained from the blister exudate. In the presence of 50% cell‐free exudate, these cells were found to proliferatein vitro.The proliferating cells possessed the morphology and functional characteristics of macrophage

ISSN:0014-2980    

DOI:10.1002/eji.1830090706

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractMacrophage‐mediated cytotoxicityin vitrowas studied by a tritiated thymidine incorporation inhibition assay as well as by microscopic examination and optical transmittance determination. It was found that macrophages from patients with malignant diseases showed cytotoxic effects on two malignant human cell lines. The cytotoxic activity was more marked in patients who were clinically tumor‐free. Some patients with benign diseases and normal subjects also exhibited cytotoxic macrophages. Macrophage‐mediated cytotoxicity (MMC) was thus nonspecific in nature. Cell‐free exudate from cancer patients did not influence MMC appreciably. The experimental methods and the possible significance of MMC are di

ISSN:0014-2980    

DOI:10.1002/eji.1830090707

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractThe sites on target cells with which cytotoxic T lymphocytes interact were characterized using three different monoclonal BALB/c anti‐CBA antibodies derived from plasma cell hybrids. The antibodies all reacted with H‐2Kkand appeared to recognizepublicspecificities H‐2.5,11 and 25, respectively. Allogeneic killing directed at products of H‐2Kkwas inhibited by all three antibodies, irrespective of the H‐2 haplotype of the responder; cytotoxicity directed at products of another allele, H‐2Kd, or of the H‐2 D region on the same target cell was not affected. The antibodies did not inhibit killer cells carrying H‐2Kk. Cytotoxic reactions against minor histocompatibility antigens, including the male‐specific antigen H‐Y, were also blocked by all three monoclonal antibodies when restricted by H‐2Kk, but not when restricted by H‐2D on the same target cell. Cytotoxic T lymphocytes thus appear to interact with their target via the same, serologically defined H‐2Kkmolecule which carries public specificities, whether they recognize it as an alloantigen or as self. This argues against the existence of separate H‐2 K‐encoded molecules recognized by killer cells only and against H‐2 specific modifications of minor histocompatibility antigens as the basis of H‐2 restriction.One of the antibodies, 27 R9, which reacted with H‐2Kkand H‐2′ and was thought to recognize specificity H‐2.25, showed a weak cytotoxic reaction but bound with a high titer to H‐2 Dk, a reaction that has not previously been described. This antibody selectively and with a very high titer inhibited male‐specific cytotoxicity restricted by H‐2Dk, but did not significantly interfere with allogeneic killing against products of the H‐2 Dkregion nor apparently with H‐2Dk‐ restricted cytotoxicity specific for other minor antigens. The results suggest the existence of at least two differe

ISSN:0014-2980    

DOI:10.1002/eji.1830090708

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractA monoclonal anti‐β2‐microglobulin (BBM.1 antibody) was produced by cell fusion between the mouse myeloma, P3‐X 63‐Ag8, and spleen cells from a BALB/c mouse immunized with Molt 4, a human T cell line. BBM.1 antibody was fully inhibited by soluble β‐microglobulin and purified HLA‐A, B antigens and reacted with humanmouse somatic cell hybrids only if they had chromosome 15 and expressed human β‐microglobulin. It was cytotoxic in complement‐dependent lysis and of the IgG class. BBM.1 and a monoclonal anti‐HLA‐A, B, C glycoprotein antibody, W6/32 (Barnstable, C. J. et al.,Cell1978.14: 9.), were used to quantitate relative amounts of β2‐microglobulin and HLA‐A, B, C glycoproteins on different human cell types. Thymocytes and the Molt 4 cell line showed a considerable excess of β2‐microglobulin over HLA‐A, B, C glycoproteins, as measured by W6/32 reactivity. B cell lines, peripheral blood lymphocytes, fibroblasts, a HeLa cell derivative, and HSB 2, another T cell line, had equal amounts. Immunological cross‐reactions between HLA‐A, B, C antigens and β‐microgloglobulin and their homologues in other species were detected with the BBM.1 and W6/32 antibodies. The W6/32 antigenic determinant appears to be more highly conserved tha

ISSN:0014-2980    

DOI:10.1002/eji.1830090709

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractAddition of supernatants from concanavalin A (Con A)‐stimulated spleen cells enable nude spleen cells to respondin vitroto a variety of antigens (in our experiments, sheep (SRBC) and horse erythrocytes (HRBC)). Experiments presented here, indicate that such nonspecific helper supernatants are in fact a polyclonal mixture of diverse, specif‐ ic activities. Con A stimulation of thoracic duct lymphocytes, specifically depleted of SRBC or HRBC‐reactive cells by the Sprent technique, results in a specific decrease in the activity to the relevant antigen. On the one hand, Con A stimulation ofin vivoactivated thymocytes results in the production of helper supernatants which are almost totally specific for the antigen used in priming.In spite of these indications of specificity, it has been impossible to absorb out helper activity from normal Con A supernatants on the corresponding antigen. Specific removal of helper activity, however, can readily be achieved by absorbing helper supernatants on complexes of antigen and early immune sera. Various control ex‐ periments demonstrate that the loss of activity in the absorbed supernatants is not due to carry‐over of antibody into the test cultures. Furthermore, the fraction of helper activity that can be specifically removed on antigen‐antibody complexes depends on the conditions used in the preparation of the supernatants; this fraction is highest when Con A activation of T cells is performed in the presence of B cells without antigen.These results suggest that “nonspecific helper factors” are a mixture of diverse molecules, some of which show specificity for variable region

ISSN:0014-2980    

DOI:10.1002/eji.1830090710

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractThe immune responses of all inbred strains of mice specific to the synthetic terpolymer poly(LGlu60LAla30LTyr10), referred to as GAT10, are characterized by the pres‐ ence of anti‐GAT antibodies which share a common (CGAT) idiotype. In this report, we describe the ability of the synthetic polymers,LGlu33LAla33LTyr33,LGlu51‐LAla34LTyr15and poly‐L(Tyr, Glu)‐DLAla–LLys [(T,G)‐A–L] to induce antibodies with CGAT idiotypic specificities. All of these polymers contain “GT”‐related deter‐ minants. Following immunization with these polymers, antisera from responder mice bind the corresponding125I‐labeled antigen and125I‐labeled poly(LGlu50LTyr50) or GAT10. These antisera shared the CGAT idiotype which is associated with the anti‐ body fraction with binding specificity for GAT10. Collectively, the present results indi‐ cate that GT‐related determinants are required for the induction of the CGAT idio‐ type. Moreover, since the immune responses to these synthetic polymers are under distinct H‐2‐linked immune response (Ir) gene control, a mouse strain can be nonre‐ sponder to one polymer and responder to another; in this case, only the latter polymer induces CGAT idiotype. Thus, although the immune responses of inbred strains of mice to different polymers are under distinct Ir gene control, the antibo

ISSN:0014-2980    

DOI:10.1002/eji.1830090711

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY