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Biomedical subjects

P Antonelli

Publications and source records attributed to P Antonelli.

31 records · Page 2Linked to original sources

Recognition by a murine monoclonal antibody of a unique epitope specific for the human alloantigen HLA-B8.

A cytotoxic murine monoclonal antibody recognizing a specific HLA alloantigen was produced from the spleen cells of a BALB/c immunized with partially purified class I glycoproteins from an HLA-A1,B8 homozygous B-lymphoblastoid cell line. The antibody, designated P8.1, was tested against cells from 521 unrelated donors. It reacted with each of the 83 donors known to be HLA-B8 positive and with no HLA-B8 negative donors (sensitivity, 100%; specificity, 100%). Immunoprecipitation with antibody P8.1 and polyacrylamide gel electrophoresis confirmed that the antigen recognized was a class I structure. Although most murine monoclonal anti-HLA antibodies previously described have recognized "public" or supertypic specificities, the identification of a monoclonal antibody specific for a "private" HLA alloantigen indicates first that the BALB/c mouse has the appropriate immune response repertoire for recognizing certain HLA allospecificities and second that HLA-B8 can be defined by a single unique epitope.

Animals↗

Specific HLA-DR4-associated histocompatibility molecules characterize patients with seropositive juvenile rheumatoid arthritis.

The structural and functional heterogeneity of HLA-DR4-associated specificities was investigated in patients with seropositive juvenile rheumatoid arthritis, a DR4-associated disease. Using a combination of HLA-D analysis by mixed lymphocyte culture and electrophoretic analysis of immunoprecipitated Ia molecules by two-dimensional polyacrylamide gels, we observed a surprisingly homogeneous pattern of HLA-D antigen expression. All patients expressed common structural products of the DR and DS loci, and 7/12 homozygous DR4 patients expressed a rare and subtle HLA-D heterozygous phenotype.

Arthritis, Juvenile↗

Electrophoretic analysis of human HLA-DR antigens from HLA-DR4 homozygous cell lines: correlation between beta-chain diversity and HLA-D.

Two-dimensional gel electrophoresis of immunoprecipitated human HLA-DR antigens from cells expressing the HLA-DR4 haplotype shows distinct clustering of beta-chain patterns. Six unique electrophoretic variants were observed among 17 HLA-DR4 homozygous cell lines (HCL) analyzed. These patterns correlate precisely with the HLA-D phenotype of the HCL donor as determined by reactivity in mixed lymphocyte culture. All DR4 HCL that belong to one of the well-defined HLA-D antigen groups (Dw4, Dw10, LD "40", LD "DYT", LD "KT2", or LD "TAS") have identical DR beta-chain patterns; DR4 HCL belonging to different HLA-D antigen groups do not. The concordance of the functional expression in mixed lymphocyte culture of a specific D phenotype with a distinct DR beta-chain pattern on gel analysis provides a direct structural basis for understanding the genetic control of HLA-D polymorphisms; HLA-D specificities as revealed by T-cell recognition in mixed lymphocyte culture thus might be accounted for by DR beta-chain polymorphisms. The extent of this beta-chain diversity within a single DR haplotype may aid in understanding variations in Ia-regulated functions, such as Ir gene control and certain disease susceptibilities.

B-Lymphocytes↗

Natural cytotoxicity of peripheral blood lymphocytes and regional lymph node cells in breast cancer in women.

Natural cytotoxicity was studied before surgery or other treatment in 83 women with primary, untreated breast cancer. Peripheral blood lymphocytes (PBL) and cytotoxicity of regional lymph node cell(s) (RLNC) were examined in a 4-hour 51Cr release assay against the target cell K-562. Results indicated that greater than one-third of breast cancer patients have more negative lymphocyte cytotoxic activity toward K-562 than do the other two-thirds. Similar results were observed for PBL of 25 patients found to have benign breast lesions. Of these patients, 23 had fibrocystic disease. The difference between these findings and findings with normal control lymphocytes studied in parallel was highly significant (P less than 0.001). The study of RLNC cytotoxicity in patients with breast cancer showed that 25% of the patients' RLNC had significant natural cytotoxic activity toward K-562. Incubation of RLNC with interferon in vitro before addition of labeled K-562 cells did not induce cytotoxicity in RLNC that did not have this activity initially.

Adult↗