Fig. 6

Expression of the human class I MHC antigens on HMC3 cells. a HMC3 were plated at the density 30,000 cells/cm² in T25 flasks, and grown for 3 days when cells were almost confluent. For the detection of class I MHC surface antigens, aliquots of 5 × 10⁵ cells in 100 μl were directly incubated with FITC-conjugated anti human HLA-ABC mouse Mab, BD Bioscience. This antibody is specific for human MHCI antigens, and does not cross react with rat MHCI antigens. Cells were analyzed by the 6-parameter (2 scatter and 4 fluorescence signals) Coulter Epics XL flow cytometer (Beckman-Coulter). Results from HMC3 cells at passage 8 are shown. Gating strategy: the analysis was obtained after gating according to morphological characteristics (not shown). Background histogram (white) indicates level of cell autofluorescence. A linear region was used for calculating percentage of positive cells. b Gel image of PCR products obtained at the end of a HLA Locus B specific amplification protocol. The 922 bp amplicons were separated by electrophoresis through 1.5% agarose gels containing 0.1 μg/ml ethidium bromide. Lines 2–3 amplification products from genomic DNA extracted by HMC3 (ATCC®CRL-3304) cells; lines 4–5 amplification products from a positive control, i.e., an anonymous human genomic DNA sample provided by ViiV Healthcare Ldt