摘要:

AbstractPrevious investigations of lambda light (L) chains in wild‐derived inbred (WDI) mouse strains revealed large variations in serum levels of this L chain type as well as differences in antibody responses in which λ chains predominate. In the present study a diverse group of WDI strains was analyzed by Southern blot analysis using probes for Vλ, Cλ1and Cλ2genes in an attempt to correlate the complement of λ genes present in these strains with their λ expression and with their taxonimic classification. All strains studied had two or three DNA sequences that strongly hybridized with a Vλ probe derived from BALB/c; most strains had Vλ, sequences on restriction fragments similar in size to Vλ1and Vλ2, sequences from BALB/c. Comparison of Cλland Cλ2genes in WDI mice to those of BALB/c revealed extensive variation both in number of hybridizing fragments and in their sizes. There were no obvious correlations observed between Cλ and Vλ patterns obtained for mouse strains of any phylogenetic group suggesting that constant and variable regions of lambda have evolved indepen‐ dently. In contrast to variations found for Cλ, a single kappa constant region gene appears to be conserved throughout the var

ISSN:0014-2980    

DOI:10.1002/eji.1830150602

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractA new model has been developed to address the question of whether T cells that traverse an allogeneic thymus during early and late life become restricted to interact,in vivo, with other leukocytes and target cells that display the major histocompatibility complex (MHC) antigens of the thymus haplotype. Chimeras were made microsur‐ gically with pairs of 24‐h‐old Xenopus embryos such that the anterior region of an embryonic chimera contained the thymus anlagen and was of one MHC genotype, whereas the posterior region contained the anlagen of all hemopoietic cells and was of another genotype. Assays to determine the MHC haplotype restriction specificity of T cells in chimeras that had been reared through metamorphosis involved: specific antibody responses (IgM and IgG) to dinitrophenylated keyhole limpet hemocyanin; rejection of minor H locus disparate skin grafts that expressed the MHC antigens of either the thymus donor or the lymphocyte donor; and mixed leukocyte culture. MHC‐mismatched chimeras displayed split tolerance since they accepted skin grafts of the thymus haplotype but had lymphocytes that proliferated in response to MHC antigens of the thymus donor strain as well as to MHC antigens of third‐party donors. IgM responses of MHC‐matched and MHC‐mismatched chimeras and of nonchimeric controls did not differ. However, the IgG responses of MHC‐mismatched thymus/ lymphocyte chimeras peaked later than those of MHC‐matched chimeras and normal controls. Data from skin grafting protocols were consistent with the proposition that there may bein vivoselection of T cells reactive to minor H antigens presented in association with the MHC antigens of the thymus rather than the MHC antigens of the lymphocytes themselves. These data suggest that although it is not absolute, there is thymic selection of the T cell rep

ISSN:0014-2980    

DOI:10.1002/eji.1830150603

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractProstaglandin E2(PGE2) and other selected agents which elevate intracellular cyclic AMP (CAMP) levels have been demonstrated to induce the appearance of surface markers in immature T lymphocytes. Thymic hormones, which are the natural induc‐ers of these markers, have long been hypothesized to act through the increase of CAMP levels. We have approached this area of investigation by studying the effects of thymulin (a serum thymus‐derived factor, coupled with Zinc) on intracellular cAMP and cyclic GMP (cGMP) levels (expressed as cAMP/cGMP ratio) and on the release of PGEzin different thymocyte subpopulations. Thymocytes were fractionated by the peanut agglutinin (PNA) technique into cortical immature PNA+and medullary mature PNA−thymocytes. The data presented in this report show that thymulin is able to increase the cAMP/cGMP ratio in PNA+and in unfractionated thymocytes, depending on its concentration, but not in PNA−thymic cells. Conversely, it is able to increase the release of PGEzby PNA−thymocytes but not by PNA+and unfractionated thymic lymphocytes. These results are consistent with the hypothesis that thymu‐ lin could act through different mechanisms depending on the differentiation stage of its target cells. In fact, it could be suggested that immature T cells could be activated by thymulin thereby increasing the cAMP/cGMP ratio, whereas more mature T cells would be further differentiated by thymulin through enhanced rele

ISSN:0014-2980    

DOI:10.1002/eji.1830150604

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe macrophage cell line, IC‐21, was found to be incapable of producing the oxygen products associated with the respiratory burst. However, IC‐21 cells were activated by lymphokine (LK) to kill intracellular (Leishmania donovaniamastigotes) and extracellular (Schistosoma mansoni larvae) parasites, as well as tumor cells. In each case, the cytotoxicity exhibited by activated IC‐21 cells and activated peritoneal mac‐ rophages was indistinguishable. However, nonactivated IC‐21 cells were unable to kill L. donovani log‐growth phase promastigotes, while nonactivated peritoneal mac‐ rophages destroyed>90% of the initial infection. These results indicate that amasti‐ gotes and schistosome larvae are susceptible to killing by nonoxidative cytotoxic mechanism induced by lymphokine activation but, on the other hand, support the concept that the killing of log‐growth phase promastigotes by nonactivated cells is dependent upon the respiratory burst. We propose that the IC‐21 cell line may be a useful model for studying nonoxidative killing functions of ac

ISSN:0014-2980    

DOI:10.1002/eji.1830150605

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractEvidence is presented that monoclonal antibodies (mAb) against some human major histocompatibility complex (MHC) gene products and human sera containing HLA antibodies strongly inhibit immune phagocytosis of anti‐D‐sensitized red blood cells by human monocytes. w6.32HL, a mAb against a monomorphic class I antigen of high cell surface density, revealed the strongest inhibition among mAb reactive with MHC class I products. mAb with preferential reactivity for monomorphic and polymorphic DR and DQ epitopes (L203, L227, IIIE3, Tü22, Genox 3.53 and IV12) were noninhibitory. Definite inhibition was also apparent with a mAb against DRw52/MT2 (I‐LR2) and with an antibody to class II antigens of high cell surface density (2MC3). Human sera containing HLA antibodies showed strong inhibition of immune phagocytosis up to a dilution of 1/1000. This inhibition could not be abrogated by platelet absorption.This indicates that human sera inhibiting immune phagocytosis may comprise at least two types of antibodies: cytotoxic HLA‐specific antibodies which may or may not be inhibitory, and inhibitory antibodies against monocytic antigens not necessarily cytotoxic. These latter antibodies may recognize HLA DR or another as yet unde‐ fined gene product within, or closely associated to, the

ISSN:0014-2980    

DOI:10.1002/eji.1830150606

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe requirement for idiotype‐specific T Cells was investigated in the T15 idiotype‐ dominant T cell‐dependent response of unprimed BALB/c and (BALB/c × C57BL/6)F1 B cells to phosphorylcholine (PC). It was first demonstrated that cloned keyhole limpet hemocyanin (KLH)‐specific, major histocompatibility complex (MHC)‐restricted T helper (Th) cells as well as heterogeneous KLH‐primed Thpopulations were capable of generating PC‐specific antibody responses in T‐depleted unprimed B cell populations cultured in the presence of PC‐KLH. The PC‐binding antibody responses generated under these conditions were indistinguishable when assayed for carrier‐hapten linkage requirements, immunoglobulin isotype (predominantly IgM) or PC affinity. Further, it was observed that the PC‐binding antibodies which were generated in the presence of these two T cell populations expressed equivalently high levels of T15 idiotype. Assaying antibody and idiotype by either enzyme‐linked immunosorbent assay or plaque‐forming cell assay yielded similar results. Since monoclonal MHC‐restricted, KLH‐specific Thcells presumably lack any additional T cell populations, these results argue against an absolute requirement for anti‐idiotypic Thcells in the generation

ISSN:0014-2980    

DOI:10.1002/eji.1830150607

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractCells from the murine B lymphoma 1.29, expressing IgM or IgA of identical idiotype, were found inducible by lipopolysaccharide to differentiate into plasma cells. Within 3 days, differentiating cells lost membrane‐bound immunoglobulin (Ig) and accumu‐ lated large quantities of intracytoplasmic Ig. At day 6 of culture, IgA secretion increased 50‐100‐fold, as determined by enzyme‐linked immunoassay. Proliferation increased for the first days of culture but decreased thereafter; by day 10 very few viable cells were present in lipopolysaccharide‐stimulated cultures. Similar results were obtained by culturing 1.29 cells in the presence of supernatants of certain B cell lines (e.g. BF0.3). The finding of a strict correlation between the inductive activity and presence of contaminatingMycoplasma fermentanssuggested that factor(s) released by mycoplasma were responsible for the mitogenic activities. This was further indicated by the findings that: (a) the supernatants of BF0.3 that were rendered free of mycoplasma were not inductive, and (b) a nonactive cell line could be made active by infection with supernatants of BF0.3 cells containing viable micro‐ organisms. Thus, supernatants of mycoplasma‐infected cell lines may act as potent polyclonal activators on both normal and malignant B lymphocytes. The ability to induce membrane Ig on 70Z/3 cells indicates that mycoplasma‐related mitogens are also active on pre‐B cells. The possibility of mycoplasma contamination should thus be carefully excluded when presumptive factors of cloned cell lines ar

ISSN:0014-2980    

DOI:10.1002/eji.1830150608

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractTwo monoclonal anti‐idiotypic antibodies (HP‐Id2o and HP‐Id22) recognizing two different public idiotopes expressed in the anti‐poly(Glu60, Ala30, Tyr10) (GAT) response were used to immunize BALB/c and C57BL/6 mice. From these animals hybridomas were isolated. From BALB/c and C57BL/6 mice eight and seven monoclonal antibodies were characterized, respectively. The reagents were classified according to the expression of the public idiotypic specificity p. GAT (recognized by a rabbit antiserum). The anti‐GAT activity and the expression of the various idiotopes characterized on anti‐GAT polyclonal and monoclonal antibodies were also studied. Most of the reagents are Ab1′‐type of antibody resembling anti‐GAT antibodies. One anti‐anti‐idiotypic monoclonal antibody (Ab3) was also isolated from BALB/c mice. This suggests that in this experimental model the repertoire induced after HP‐Id immunization and antigen stimulation is comparable. The idiotypic analysis of a large number of anti‐GAT and of Ab1′ monoclonal antibodies suggests that only two public idiotopes are involv

ISSN:0014-2980    

DOI:10.1002/eji.1830150609

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractBALB/c and BALB/c nu/nu mice were shown to express to a variable extent in their response against dextran B1355S (Dex), an idiotype which is present on the Dex‐reactive BALB/c myeloma protein MOPC104E. Injection of minute amounts of syngeneic anti‐MOPC 104E idiotype antisera into neonatal euthymic or athymic BALB/c mice suppressed this idiotype in the Dex‐specific response of the adult animals. When spleen cells from suppressed BALB/c mice were transferred into irradi‐ ated BALB Ighbmice the state of suppression persisted. Data are discussed with respect to possible mechanisms regulating expression of this i

ISSN:0014-2980    

DOI:10.1002/eji.1830150610

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractIgG1induction factor elevates the IgGlresponse induced by lipopolysaccharide and suppresses the lipopolysaccharide‐induced IgG3and IgGZbresponses in cultures of mouse spleen cells. We have developed new T cell lines secreting this factor by cloning mixed lymphocyte culture populations. Using supernatants of one of these T cell lines it was found that the assay is quantitative, reproducible and accurate, both when induction of IgGlas well as reduction of IgG3and IgG2bwere measured. Using this analysis, different conditions to induce maximal production of the factor were tested. The cell line was thereafter used as fusion partner with a T cell lymphoma. The hybrids were selected in the presence of T cell growth factor and all of them secreted IgGlinduction facto

ISSN:0014-2980    

DOI:10.1002/eji.1830150611

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY