Quality control of HIV cultures in a clinical retrovirology laboratory

The culture of primary HIV isolates requires fresh phytohemagglutinin (PHA) stimulated peripheral blood mononuclear cells (PBMC) from seronegative donors. The variation inherent in donor cells, obtained from many different individuals, might affect the likelihood of virus isolation. We developed a quality control (QC) procedure which could determine quantitatively the susceptibility of random donor cells to HIV infection. The QC reagents consisted of cells and supernatants infected with a syncytium-inducing clinical isolate of HIV. Six 5-fold dilutions of QC cells (starting at 1000 cells) and supernatant (starting at a 1:200 dilution) were cultured in parallel with 1 x 10(6) 2-3-day-old PHA stimulated donor cells. After 7 or 14 days the resulting culture supernatant was tested for syncytia formation with MT-2 cells. A total of 127 sequential donors were tested over an 11 month period. All but one donor PBMC preparation was capable of being infected by the QC reagents (and this particular donor was permissive for several other primary isolates). The standard variation observed among all cultures was about one 5-fold dilution. The coefficient of variation ranged from 10.7 to 17.3%. These results suggest that the mononuclear cells from most, if not all, individuals are permissive for HIV to approximately the same level. Other quality control measures used in the laboratory are described.