摘要:

The protocols for the induction of hapten‐specific suppressor T cells (Ts) and hapten‐specific cytotoxic T cells (Tc) are essentially the same. Hence, to exclude or support the possibility of an apparent suppression of B‐cell responsiveness by elimination of B cells due to cytotoxic cells, limiting dilution cultures were concomitantly tested for suppression of a primary B‐cell response against trinitrophenol (TNP), and cytotoxic activity towards a TNP‐haptenized anti‐TNP IgM hybridoma. When compared with the spleen cells (SC) of untreated Balb/c mice, the frequency of Tcwas found to be increased after in vivo or in vitro induction of TNP‐specific Ts(via intravenous injection of TNP‐haptenized tympocytes or cocultivation of SC with haptenized lymphocytes). Despite this synchronous increase of hapten‐specific Tsand Tc, the number of wells displaying both cytotoxic and suppressive activity did not exceed the number of wells that were expected to contain Tsand Tc. Hence, in the system described, hapten‐specific Tcdid not lyse anti‐hapten antibody‐producing B cells to any measurable extent, and suppression of a B‐cell response by in vivo or in vitro‐induced Tswas independent o

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02063.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

The lectin from tomato (Lycopersicon esculentum) fruits was found to be non‐mitogenic for human lymphocytes in culture and actually suppressed spontaneous DNA synthesis. It also inhibited the transformation of human peripheral blood Lymphocytes induced by recall antigens or allogeneic cells in vitro. This inhibition was most effective when the lectin was present from the beginning of the culture period, and could be abolished by the simultaneous addition of oligomers of N‐acetylglucosamine The tomato lectin was able to bind to several major lymphocyte cell surface glycoproteins, but not to the major histocompatibility (HLA) antigens. The binding of tomato lectin to lymphocytes could be inhibited by wheal germ agglutinin (WGA). but not by concanavalin A. Tomato lectin could agglutinate monocytes and B lymphocytes as well as T lymphocytes. Human serum used to supplement the culture medium supporting lymphocyte transformation was equally effective after passage through a tomato lectin‐Sepharose column. The inhibition of lymphocyte transformation brought about by tomato lectin was not stopped by exogenously added interleukin 1 and/or interleukin ‐2 even at very high concent

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02064.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Human peripheral blood monocyte subsets with and without Fc receptor for human IgG are known to suppress (FcR+) and enhance (FcR−) pokeweed mitogen‐induccd polyclonal immunoglobulin synthesis in vitro. The ability of these subsets to modulate immunoglobulin production in the presence or absence OKT8−T cells and under conditions where suppressor T‐cells activation was blocked by irradiation or mitomycin C was studied. It was shown that, regardless of the presence or absence of suppressor T cells, FcR−monocytes can suppress immunoglobulin production if their number in culture exceeds 20%. However, at lower numbers this monocyte sunset was suppressive only when suppressor T cells were activated. The suppressor T‐cell activation was shown to be independent of the predominant presence of the FcR+or FcR monocyte subset. Moreover, the enhancing effect of FcR−monocytes was not caused by their interference with suppressor T‐

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02065.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

To shed further light on the induction and characterization of thymus‐derived mast cells, we cultured a variety of cell populations from murine thymus tissues (Balb/e) in the presence or absence of interleukin 3 (IL‐3). The whole cell population and the nun‐adherent T cell‐depleted population developed mast cells. The morphological studies revealed granulated cells: the granules were stained with toluidine blue, alcian blue (pH 3.0). and metachromatic dyes. Electron microscope revealed altered mast cell granules. These cells contained relatively low amounts of histamine (‐ 1700 ng/106cells), were IL.‐3 (but not IL‐2)‐dependent, and did not possess T‐cell. B‐cell. or macrophage markers. No phagocytosis was observed. the cells also had 20α‐hydroxysteroid dehydrogenase, and both IL‐3 and IgE (145,600/cell) high affinity receptors. The frequency analysis showed 17 precursor cells per 106thymic cells. The results indicate that the thymus indeed contains progenitors of mast cells responsive to IL‐3, and that the mast cells are derived from non‐T. non‐phagocytic. and non‐adherent cells of the thymus. Their T‐lymphocyte product (IL.‐3) dependency, ultrastructural appearance, granular stainability, and low content of histamine may support the view that the mast cells originating from the thymus probably b

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02066.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Mice immunized with rat erythrocytes develop anti‐erythrocyte autoantibodies, distinct anti‐rat erythrocyte agglutinins, and suppressor‐inducer cells. which regulate the production of autoantibody but not anti‐rat erythrocyte agglutinins upon transfer to naive recipients. In this report, we have tried to determine the specificity of the suppressor‐inducer cells. CBA/N mice (which express an X‐linked genetic B‐lymphocyte defect) immunized with rat erythrocytes developed no autoantibodies but normal levels of anti‐rat erythrocyte antibodies and suppressor‐inducer cells, thereby suggesting that neither idiotypes on autoreactive B cells nor idiotypes on autoantibody itself, stimulate suppressor‐inducer cells. In contrast, rat erythrocyte‐primed spleen cells suppressed both a primary 2,4,6 trinitrophenyl (TNP) response and anti‐erythrocyte autoantibody production (but not anti‐rat erythrocyte antibodies) upon transfer to naive recipients and challenge with TNP‐rat erythrocytes. It is considered that the suppressor‐inducer cells are carrier‐specific and that they are not simulated by idiotypes on either auto

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02067.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

The results show that monoclonal IgD reacts specifically with ricinus agglutinin (molecular weight 120.000) (RcA1). The reaction between IgD and RcA1 was inhibited by galactose and lactose but not by glucose, indicating that the interaction is mediated by galactose containing carbohydrate units located in or near the σ‐hinge region. Affinity chromatography on RcA1‐Sepharose 4B was successfully used lo isolate monoclonal IgD from the IgD myeloma pl

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02068.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

The suppressive effect of normal rat peritoneal exudate cells (PEC) on concanavalin A (Con‐A)‐induced lymphocyte proliferation was studied. Partial suppression of proliferation was obtained by adding 3% PEC and complete suppression wits observed with 6% PEC. The suppressive effect was mediated by W3/25 plastic‐adherent macrophages, which constitute about 60 % of normal PEC. Addition of PEC prior to. simultaneously with, or 24 h after, but not 48 h after, the stimulation of lymphocytes with Con A resulted in suppression. Suppressed cultures produced normal or slightly increased amounts of interleukin 2 (IL‐2). but the expression of the IL‐2 receptor on lymphocytes was decreased. Pre‐exposure of PEC to gamma interferon (IFN‐γ) resulted in decreased suppression, whereas IFN‐γ added simultaneously with the lymphocytes had no effect. Catalase reversed PEC‐induecd suppression and significant synergistic effects were recorded when combined with IFN‐γ. Even completely suppressed cultures were effectively protected from suppression. Indomethacin and combinations of indomethacin with catalase or IFN‐γ did not result in additional protection Irons

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02069.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Components of calf thymus extract dialysable under acid conditions contained two natural killer (NK) cytotoxicity‐stimulating factors. CSFa and CSFb, which could be separated by ion exchange chromatography. NK cytotoxicity of human peripheral blood mononuclear cells (PBMC) against human K562 tumour cells was strongly enhanced after 72 h pre‐incubation with the factors. The CSFa/b‐specific stimulation of PBMC required the presence of monocytes. The cytotoxic effector cells activated during pre‐incubation of PBMC with the CSF were identified as monocytes and as NK cells present in the fraction of large granular lymphocytes (LGL). Selective cell depletion studies with LGL‐containing subpopulations (free of monocytes) allowed factor‐specific discrimination of the activated LGL. Pre‐incubation of PBMC with CSFa stimulated NK cytotoxicity of LGL (Leu 7+11; T8−), whereas pre‐incubation with CSFb resulted in stimulation of LGL (Leu 7+11+; T8−). The biological effects of CSFa and CSFb could be further distinguished by analysis of surface marker expression during incubation of PBMC. CSFb scarcely influenced T4 expression, hut strongly enhanced the expression of TK and that of transferrin receptor, whereas CSFa had no significant influence on the expression of these three surface markers. Both factors induced a drastic reduction of tumour take incidence or tumour development in mice when applied before and aft

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02070.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

The present longitudinal study was designed to characterize immunosuppression during acutePlasmodiu, falciparuminfection, during the treatment and up to 1 month after the acute stage. The proliferative responses of blood mononuclear cells (BMNC) isolated from non‐immune and semi‐immune malaria patients and controls to mitogens and twoPlasmodium‐derived stimulators (merozoites, Meroz. and soluble purified antigen, Spag) and non‐related antigens were measured by [2H]thymidine incorporation. BMNC isolated before treatment (day 0) from the non‐immune patients did not respond to Meroz, whereas those from controls showed a significantly higher response. The SPag responses were also low in BMNC isolated on day 0 and increased in both the non‐immune and the semi‐immune patients during the observation period. These findings indicate that during malaria there is a depression of the parasite‐specific proliferative response. The subset composition of BMNC isolated from non‐immune patients was studied in a FACS analyser. The mean cell volumes of both Leu 2’and Leu.3 cells were increased during the acute phase of the infection, indicating that malaria infection results in activation of both T‐helper and T‐suppressor cells. There was no overall reduction of the response to mitogens on day 0. However. 3 days alter initiation of the treatment the mitogen response was decreased.‘This finding indicates that it is important to distinguish between the effects of malaria infect

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02071.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

We have recently demonstrated the occurrence of functional circulating soluble cell‐free Fcγ2b/γ1 receptor in normal mouse serum by means of the 2.4G2 rat monoclonal antibody. With the solid phase radioimmunoassay described previously, we report here a dramatic increase in the level of circulating soluble cell‐free Fcγ2b/γ1 inSchistosoma mansoni‐ infected mice individually tested before and on days 22, 41, 62, and 82 after infection. This increase was statistically highly significant when the five measurements from each mouse were compared, and also when the entire group of infected mice was compared with the stable level of Cf‐ Fcγ2b/γ1R measured in strain‐, sex‐, and age‐matched control mice individually tested on the same days. This increase was commensurate with a rise in the amount of IgG detected in the sera of theS. mansoni‐infected mice. Thus, infection seems to be one of the factors that modulate the expression of such soluble Cf‐Fcγ2b/γ1R in mouse serum. Furthermore, the experimental device reported here for the production of high levels of Cf‐ Fcγ2b/γ1R by infection (in this case by parasitic infection) could serve as a model for obtaining large quantities of serum Cf‐ Fcγ2b/γ1R for further purification. Lastly, we point out that, by establishing a functional relationship with circulating IgG, such soluble Cf‐ Fcγ2b/γ1R may modulate some of the functions in which the Fc p

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1986.tb02072.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY