ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01026.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01027.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01028.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01029.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01030.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Cell‐free synovial fluid (SF) obtained from patients with rheumatoid arthritis contains a helper factor(s) capable of augmenting the generation of plaque‐forming cells (PFC) in pokeweed mitogen (PWM)‐stimulated normal peripheral blood mononuclear cells (PBMC). This helper factor behaves like a polyclonal B‐cell activator, in that it triggers the formation of IgM, IgG. and IgA PFC. However, SF has little or no effect on the proliferation of PWM‐activaled PBMC. Furthermore, SF was capable of replacing T cells for PWM‐induced differentiation but not proliferation of enriched human blood B lymphocytes. No helper factor or T‐ccll‐replacing activity was found in SF from patients with traumatic synovilis. Fractionation of SF containing helper activity on staphylococcal protein A column indicated that the activity is induced by biologically active molecules distinct from materials that preferentially hind to protein A such as IgG immune complexes. We conclude that the present activity has striking similarities to the recently described B‐cell differentiation factor that is produced by specifically activated T‐

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01031.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

HLA class II determinants were analysed for their role in monoeyte‐T‐cell infractions in the prolifeniuve response to purified protein derivative (PPD). Allogeneic cell combinations of monocytes and T cells were tested with a range of suboptimal PPD concentrations. For each cell combination tested, a summary measure to characterize the antigen‐induced response curve was calculated by means of regression analysis of the response in the dose of PPD added, thus obviating a further need to correct for mixed lymphocyte reactivity. In 200 distinct monocyte‐T‐cell combinations. HLA‐DR appeared io be the major restricting clement. Additionally, a marginal influence of HLA‐MB or ‐MT matching was observed and no evidence of HLA‐SB‐restricted responses. Remarkably, the HLA‐MB1 specificity was significantly associated with low responsiveness in DR sharing monocyte‐T‐cell combinations, indicating a modulating role of MB1 in DR‐

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01032.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The effect of 5′‐methylthioadenosine (MTA) on human natural killer (NK) cell activity was examined and compared with the effect of 3‐deazaadenosine (c3‐ado) and periodate‐oxidized adenosine (ado‐ox). MTA inhibited NK cell activity in concentrations above 30 μM, but in concentrations below 10 μM a slight enhancing effect was often observed. C3‐ado and ado‐ox were 10 and 3 times more potent, respectively, as inhibitory agents and did not increase NK cell activity in low concentrations. The inhibitory effect of c3‐ado was unaffected by preincubation of the cells but was enhanced by the addition of μ‐homocysteine. In concentrations that caused inhibition of NK cell activity all three agents caused a fall in the methylation index (AdoMet/AdoHcy) but no or an inconsistent effect on the level of cyclic AMP. An increase in the level of AdoHcy was observed already after 1 μ of incubation but was more pronounced after 4 μ of preincubation with the adenosine derivatives. The inhibition of cytotoxicity was mainly on their initiation of lysis, with a smaller effect on target cell binding Antibody‐dependent cellular cytotoxicity and lectin‐dependent cellular cytotoxicity appeared to be less sensitive to inhibition by c3‐ado. Our results show that several adenosinc analogues inhibit NK‐cell‐mediated cytotoxicity in parallel with a decreased methylation index. The results suggest that a methylation step is critical in lymphocyte‐mediated cytotoxicity and that NK cell activity is more sensitive to inhibition of this step than antibo

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01033.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

An in vitro system is described which supports the primary induction of T cells able to help in the induction of delayed‐type hypersensitivity. This system is used to demonstrate that hapten‐Ficoll conjugates induce potent hapten‐specific T cells with this function. These type‐II ‘thymus‐independent’ antigens are thus able to induce specific regulatory T cells. These helper T cells are similar to those induced by classical thymus‐dependent antigens in that they are specific for antigen rather than idiotype and act by a l

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01034.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

After 3–5 days of in vitro culture, peritoneal cells from untreated Oil mice produce autoantibodies specific for autoantigens in the membranes of mouse crythrocytes. The autoantigens are exposed in vitro by treating mouse erythrocytes with the proteolytic enzyme bromclain. Limiting‐dilution cell culture techniques were used to determine the frequency of the autoreactive B cells. Cells were cultured in Terasaki trays at 10–200 cells/well. Autoantibody production was assayed with an in situ plaque‐forming cell (RFC) assay. On average, one autoantibody precursor cell was detected for every 150–200 peritoneal cells cultured. This precursor frequency was increased to 1 in 50 by the addition of lipopolysaccharide (LPS) and dextran sulphate (DS) to the culture medium The addition of a culture supernatant from an EL‐4 lmphoma subline also induced a high proportion of the peritoneal cells to secrete autoantibodies However, it was not possible to determine thefrequency of PFC accurately because at limning numbers of peritoneal cells the effects of EL4 affected more than one limiting variable. Significant cell division was observed in cultures to which LPS/DS had been added, in contrast to untreated cultures to which EL4 supernatant was added. The results show that high numbers of autoreactive B cells committed to self antigens are present in the peritoneal cavity and that these cells under the influence of appropriate cytokines can differentiate in vitro, even without proliferation, into autoantibody secretors. The cell type or types releasing the cytokines remain to be

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1984.tb01035.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY