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M Tongio

Publications and source records attributed to M Tongio.

4 recordsLinked to original sources
PubMed1994

An optimized method for routine HLA-B27 screening using flow cytometry.

Flow cytometry and monoclonal antibodies are promising tools for HLA-antigen detection. Previous approaches have been hampered by the lack of a carefully standardized system for calibration and sample analysis. A new system for HLA-B27 screening was developed using a FACScan flow cytometer, software for automated calibration and analysis, calibration beads, and the anti-HLA-B27-FITC/anti-Leu4-PE (CD3) monoclonal antibodies. The median fluorescence channel result for the HLA-B27-FITC signal of CD3+ T lymphocytes is compared to a decision marker. Values lower than this threshold are read as HLA-B27 negative and those above are recommended for retesting with the classic microcytotoxicity assay on the presumption of HLA-B27 positivity. The anti-HLA-B27 antibody reacts with all six HLA-B27 subtypes and shows a weaker binding to HLA-B7. The screening test results were compared with those from the microcytotoxicity assay for HLA-typing in studies involving several European centers. The observed sensitivity was 100% (95% Cl:98.6-100) and the specificity was 97.4% (95% Cl: 96.4-98.3). Other performance studies verified the reproducibility and reliability of results obtained with the screening system.

Anticoagulants↗
PubMed1994

[T-lymphocyte population in the normal human cornea].

T-lymphocytes of the normal human cornea (10 donors) were studied from corneal fragments cultured in IL-2 medium. Their phenotypic repertoire was performed by FACS analysis using the following monoclonal antibodies: CD3, CD19, CD4, CD29, CD18, CD16, CD56, CD25, TCR alpha/beta, TCR alpha/delta. Functional analysis was done by proliferation assays (PLT). T cell growth was more often obtained from peripheral (n = 7/10) than central corneal parts (n = 3/10). Most of the cultured cells carried the CD8 marker, were activated (HLA-DR+) and had a cytotoxic function (CD 18+). All their T cell-receptors were alpha/beta type. No NK cells could be detected. No specific proliferation was observed when tested on a panel of HLA typed presenting cells. This study demonstrated activated T-lymphocytes in the normal human cornea. These activated, cytotoxic CD8+ lymphocytes could participate in the particular immunological characteristics of the eye.

CD8 Antigens↗