摘要:

AbstractA fine specificity analysis of influenza hemagglutinin‐specific IAk‐restricted T cell clones using natural virus variants of the H3N2 subtype, monoclonal antibody‐selected variants and a synthetic peptide corresponding to a variable region of the HA1polypeptide has provided insight on the structural basis for T cell recognition. A glycine to argine substitution at HA1135 abrogates recognition by a panel of T cell clones which, according to their reactivity for natural virus variants, have different antigenic specificities: three clones recognize a synthetic peptide (HA1residues 118–138) but fail to recognize the monoclonal antibody‐selected mutant (Gly135/Arg). There is no correlation, however, between differences in T cell specificity for the natural virus variants and HA1amino acid sequences in this region. Two further clones have a reduced proliferative response to mutant recognize a completely different spectrum of natural variants, and only one of these clones recognizes the synthetic peptide. We speculate that influenza hemagglutinin employs a common strategy during antigenic drift to evade antibody recognitionandeffective processing/presentation to subtype‐specific T

ISSN:0014-2980    

DOI:10.1002/eji.1830170122

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe expression of Pgp‐1 (Ly24) by subpopulations of thymocytes was investigated and a subpopulation of Lyt‐2−/L3T4−/J11d−thymocytes was identified which contained significant numbers (80%) of Pgp‐1+cells. Among freshly isolated lymph node T cells but not cortisone‐resistant thymocytes, Pgp‐1 expression was heterogeneous. Stimulation of T lymphocytes with either concanavalin A or the combination of phorbol myristate acetate plus calcium ionophore resulted in increased Pgp‐1 expression which was found to be regulated independently of DNA synthesis and interleukin 2 receptor expression. T cells in the cerebrospinal fluid exudate of mice infected with lymphocytic choriomeningitis virus were also f

ISSN:0014-2980    

DOI:10.1002/eji.1830170123

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractMice simultaneously expressing the mutationsnudeand X‐linked immune deficiency (xid) were previously shown to have pro‐B cells and/or early pre‐B cells while lacking Cμ+and surface Ig+cells. We now report that thymus grafts restore both T cells and B cells innude‐xidmice. By the use of Thy‐1 and Igh allogeneic donors it was shown that both the T and B cells were host derived. The B cells had a functional phenotype typical ofxidmice. It is concluded that the maturation ofxidB cells past the pro‐B or early pre‐B stage is T

ISSN:0014-2980    

DOI:10.1002/eji.1830170124

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractIndomethacin was tested for its ability to augment the cytotoxic capacity of cultured bone marrow‐derived macrophages (MΦ) against P815 and YAC‐1 tumor cells. MΦ were obtained from the bone marrow of C57BL/6 mice precultured for 10–14 days and were virtually 100 percent pure. By addition of indomethacin these cells were activated to kill tumor cells in a 4‐h and 18‐h Cr‐release assay. Since indomethacin is a potent inhibitor of the cyclooxygenase system, MΦ were treated with prostaglandin E2. This treatment partially reversed indomethacin‐induced cytotoxicity. Addition of other cyclooxygenase inhibitors such as acetyl‐salicylic‐acid, diclofenac or carprofen also induced cytotoxicity in bone marrow‐derived MΦ. In all experiments we failed to detect any production of interferon. Addition of anti‐interferon did not alter the cytolytic capacities demonstrating that endogenously induced interferon was not relevant in this mechanism. Our data show that cyclooxygenase inhibitors induce cytolytic activity of murine MΦ not only against a MΦ target but also against YAC‐1 cells usually considered to be tar

ISSN:0014-2980    

DOI:10.1002/eji.1830170125

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe capacity of small, soluble immune complexes (SIC) to rearrange into larger aggregates, through additional antibody‐antigen bridge formation, on a receptor‐bearing cell surface has previously been shown to play an important role in enhancing the uptake and ingestion of SIC by macrophages and has been implicated in the efficient clearance of SICin vivo. In this report, we extend the study to investigate the role of SIC aggregation in triggering a respiratory burst in macrophages. SIC were found to be more efficient trigger signals than nonaggregating, antigen‐free IgG oligomers of similar average size in that they induced a more rapid respiratory burst response that was between 2‐ and 6‐fold greater in magnitude. The implications of these findings are

ISSN:0014-2980    

DOI:10.1002/eji.1830170126

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractInterferon‐γ induces surface expression of interleukin 2 (IL 2) receptors on human monocytes and the monocytic cell line U937. Freshly prepared peripheral blood monocytes and U937 cells were found to lack detectable IL2 mRNA, but exposure of these cells to interferon‐γ induced IL2 receptor message at 6 h of culture. At least two IL2 receptor transcripts were detected (3.5 and 1.5 kb) in both monocytes and U937 cells, similar in size to IL2 receptor transcripts in activated T cells. These results show that interferon‐γ induces expression of the monocyte IL2 recep

ISSN:0014-2980    

DOI:10.1002/eji.1830170127

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

ISSN:0014-2980    

DOI:10.1002/eji.1830170128

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY

ISSN:0014-2980    

DOI:10.1002/eji.1830170101

出版商:WILEY‐VCH Verlag GmbH    

年代:1987

数据来源: WILEY