ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03085.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03086.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

The role of protein kinase C (PKC) in TNFα‐induced activation of endothelial adhesion molecules ICAM‐1 and VCAM‐1 was analysed. Phorbol myristate acetate, which is known to activate PKC, was able lo mimic TNFα‐induced up‐regulation of ICAM‐1 and partly also VCAM‐1 expression. Similarly a PKC inhibitor, H7, but not another kinase inhibitor. HA1004, inhibited TNFα‐induced enhancement of ICAM‐1 expression at both the mRNA and the protein level. Moreover we were able to measure a transient PKC activation peak at 16 min after TNFα induction in endothelial cells analysed by phorbol‐dibutyrate binding. These results indicate that the TNFα‐induced effect on the regulation of endothelial adhesion molecule expression is at least partly

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03087.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03088.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Non‐specific antibody production usually accompanies the T‐cell‐regulated B‐cell response. In this papaer the Machanisms involved in non‐MHC‐restricted T‐cell interaction were studied. As previously shown for NK cells, activated B cells induce IFN‐α and TNFα production in non MHC‐restricted cytotoxic T lymphocytes (NrCTL). Using an in vitro model system, we demonstrate that direct cell cell interactions are required to induce these cytokines in NrCTL. Receptor ligand systems involed are leucocyte function antigen‐1/intercellular adhesion molecule‐1 (LFA‐1/ICAM‐1)(CDlla, CD18/CDM).Tn/LFA‐3(CD2, CD58), andtheclonoty‐pic T‐cell receptor (TCR) strueture NKTa of JT9/JTI0 with ils no!i‐MHC‐related target antigen TNKtar(4F2), Cytokine produclion can be induced by activating motiockmahmtibodics against CD2R, Antibodies againsi the elonotypic TCR (NKTa) or CD3 had no cylokine‐iiiduciiig effect on NrCTL cullured alone, but were able to retrieve the effect of blocking the target antigen on co‐cuhured B eells. We eould lurther demonstrate that the inhibition of the TCR/targel antigen interaction eould be overcome by elose cell cell contae! culture conditions. From these findings il i s concluded that the role of the TCR in non‐MHC‐reslricted cell cell interaction is to facilitate LFA‐l. lCAM‐1‐mediated elfectorlarget adhesion in a specific way rather than lo mediate direct activati

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03089.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

We investigated the relative role of C3bi‐CR3 interaetion in the binding and phagocytosis of EAC43 by mouse peritoneal macrophages. Anti‐Mac‐1 F(ab′)2markedly inhibited the binding and lymphokine‐induced phagocytosis of both EAC43b and EAC43bi, Fifty per cent inhibition of attachment and phagocytosis occurred at 1 μml of anti‐Mac‐1 F(ab′)2in the incubation media. On the other hand, ElgG binding and phagocytosis were not inhibited at all even at a concentration of 10 μ/ml. Depletion of divalent ealions from the incubalion media abolished EAC43b and EAC43bi rosettes but not ElgG rosettes or phagocytosis. These data suggested that both EAC43b and EAC43bi binding to macrophages were mediated via CR3.Because a drastic decrease of FAC43bi rosettes was observed in the case of EAC43bi cells prepared with smaller amounts of C3, a small eontamination of C3bi molecules on EAC43b, itself, cannot explain the efficient attachment of EAC43b, We propose that EAC43b on the macrophage surface can be quickly converted to EAC43bi, forming EAC43bi rosettes, and that those erythrocytes are vigorously ingested by lymphokine‐activated macrophages. In accordance with this hypothesis, we demonstrated that EAC43b was converted to E AC43bi in the medium in whicb macrophage

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03090.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Specific stimulation of the antibody response to protein iintigcns by IgG antibodies was studied in vivo‐The response to TNP‐coupled keyhole limpet haemocyanin (KLH‐TNP) was enhanced by a TNP‐spcciftc IgG monoclonal antibody, 7B4, as measured both in ELISA (enzyme‐linked immunosorbent assay) and by ELISPOT (enzyme‐linked immunospot) method. Enhancement was seen when using both high and low doses of antigen and antibody. The antibody response to TNP‐coupled bovine serum albumin (BSA‐TNP), bul not to TNP‐couplcd ovalbumin (OA‐TNP), tetanus toxoid (TT‐TNP) or diphtheria toxoid (DT‐TNP). was also etficiently augmented by 7B4, Enhancement was seen when using both high and low coupling ratio of TNP to KLH, The fact that IgG‐mediiited enhancement is seen under many ditVerent experimental conditions suggests that it is a physiologically relevant phenomenon. In order lo enhance the response to KLH‐TNP and BSA‐TNP, 7B4 had lo be injected while antigen was circulating in blood. This supports that igG‐mediated stimulation acts by concentrating circulatin

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03091.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

TMA (thermostable macromolecular antigens) are major mycobactcrial complexes present in all mycobticteria. We have purified A36, the TMA complex ofM. paratuberculosis, the etiological agent of paratuberculosis (Johne's disease), and shown by the immune electron microscopy approach its presentation at the cell surface. The immunodominance of the A36 complex in Johne's disease was suggested by comparative ELISA analysis of infected bovine sera, using either A36 orM. paratuberculosistotal soluble sonicate as antigens. The cross‐reactivity of TMA complexes from diifcrcnt tnycobacteria was evaluated by immunocn/ymometri c measurements. Percentage of shared epifopes was high tor the coupleM. paratuberculosis‐ M. avium. and somewhat lower for the coupleM. paratuberculosis and M. bovisImmunological kinship betweenM. paratuberculosisand M. leprae was suggested by the finding that oul of eleven anti‐M. lepraemonoclonals, four cross‐reacted with A36 proteins. The specificiiy missing al the level of the whole A36 complex was sought at the level of its protein components. Comparative immunoblot analysis of electrophoresed A36 proteins indicated three of them to contain epitopes not shared byM. bovisproteins, and one of them to contain epitopes specific wilh respect loM. avium, M. bovis and M. phlei.The latter component, a 34‐kDa protein, could be an ideal reagent for a serological tesi for, Johne's disease, being immunodominant in infected cattle and endowed with species‐specif

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03092.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Purified populations and clones of human γδ T cells were examined for their ability to interact with extracellular matrix (ECM) components. The stimulation of these cells with phorbol ester induced cellular adhesion for ECM, The adhesion structures for fibronectin and collagen were shown to be members of the CD29 integrin family. The expression patterns of β1, β2 and β3, integrin‐s by these cells were examined. The receptor expression and utilization patterns suggest that αβ, γδ T cells and B cells have similar repertoires of adhesion

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03093.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Changes in the intracellular calcium ion concentration ([Ca2+]i) of monocytes. granulocytes. and NK eells have been studied following either (1) independent cross‐linking of Fcγ receptors (FcγR) I, H, or III, with F(abγ')2fragments of monoclonal antibodies: or (2) linking ofa selected FcγR to a tumour cell target with bispecilic F(ab'γ)2antibodies. Upon cross‐linking each FcγR with antibody an increase in the ([Ca2+]i), was observed, although all receptors apart from FcγRIII on NK cells required additional cross‐linking with an anti‐mouse Fab', These results indicale that each type of receptor can transduce signals to the cell independently, Bispecific antibodies (anti‐FcyR X anti‐target) linking cytotoxic FcyR‐bearing effector cells to tumour target cells also mediated increases in ([Ca2+]i) for all FcγR tested except for FcγRIII on granulocytes. The failure to transduce a signal via ihis receptor may be related to the GPI link, which is in contrast to the transmembrane link of Fcγ RIII on NK cells. Significant lysis of tumour cell targets occurred when bispecific antibodies recruited NK cells or monocytes. bul not granulocytes, via FcγR. Chelation of intracellular Ca2+iin the effector cells redueed the observed lysis, suggesting a role for Ca2+iin the pathways

ISSN:0300-9475    

DOI:10.1111/j.1365-3083.1992.tb03094.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY