Combination of whole blood culture and a rapid and sensitive cell assay for the determination of the cytopathogenicity of human immunodeficiency virus type-1 isolates.

It has been reported that in vitro biological properties of human immunodeficiency virus type 1 (HIV-1) isolates from patients are correlated with the prognosis of HIV-1 infection. A rapid assay was developed to study the phenotype of HIV-1 isolates. The P4 cell line is a HIV-1 infectible Hela CD4 cell carrying the bacterial LacZ gene under the control of the HIV-1 LTR (long terminal repeat). Conventional peripheral blood mononuclear cells (PBMCs) co-culture and heparinized whole blood (HWB) co-culture with normal PBMCs were used for HIV-1 isolated strains from 17 HIV-1-infected patients. The sensitivity of P4 cells was higher than that of MT-2 cells for detecting syncytia induced by HIV-1LAI (lymphadenopathy-associated virus). Like MT-2 cells, P4 cells enable the detection of syncytium inducing strains isolated in peripheral blood mononuclear cells (PBMCs) and HWB cultures. HIV-1 isolates with both culture methods from certain patients induced cytolysis without syncytium in P4 cells but had no cytopathic effect on MT-2 cells. The experiments are in favour of the direct effect of HIV-1 isolates of these patients in the lysis of P4 cells but its mechanism has not been elucidated. It was shown that the combination of whole blood culture for HIV-1 isolation and phenotype study with P4 cell assay is rapid and sensitive and could be used to monitor HIV-1-infected patients.