A nested PCR for the detection of CMV in blood mononuclear cells from HIV infected patients.

Abstract

The Human Cytomegalovirus, a member of the Herpesvirus family, is a relatively non-pathogenic virus except in those individuals whose immune systems have not fully developed (newborns) or are immunosuppressed (transplant patients) or immunodeficient (individuals with AIDS). A rapid test to detect the virus in clinical samples is needed in order to assess the status of an HCMV infection and to monitor the virus in an individual over time. Faced with the alternative detection systems such as viral culture, immunofluorescence assays and DNA probing the polymerase chain reaction is an attractive choice because of its rapidity and unrivalled sensitivity. Nested polymerase chain reaction for HCMV was used in the present work in order to determine how useful it is in the detection of the virus in peripheral blood samples. Two nested assays were evaluated and optimized using blood samples from HIV-1 seronegative blood donors, HIV-1 seropositive asymptomatic individuals and individuals with AIDS. The results show that the assay is rapid, sensitive and specific. Furthermore, the virus was readily detectable by PCR in individuals with AIDS while it is infrequently found in the other two groups. Finally, the PCR results were positive at 14 and 7 months, respectively, in two individuals with AIDS prior to the development of overt HCMV mediated disease suggesting that PCR is a useful monitoring tool in individuals at high risk for HCMV disease. PCR has many applications in basic and applied research and potentially in the detection of infectious diseases. The results here suggest that its use may help to predict who may and may not develop the potentially sight and life-threatening diseases caused by HCMV.