ABSTRACT
Four HHV-6 strains were initially isolated during attempts to observe HIV-1 replication in cultured primary lymphocytes from 48 patients with AIDS. HHV-6 DNA from each strain was extracted from primary cell cultures and amplified using specific primers in a nested polymerase chain reaction (PCR) assay. All HHV-6 strains were classified as B variants by submitting the PCR products to the digestion of two restriction enzymes (Hind III and Bgl II). Since in primary cultures, the appearance of HHV-6 cytopathic effect was followed by a progressive reduction of HIV-1 replication, we tried to reproduce the observed inhibition in vitro. Two HHV-6 strains, used throughout the experiments, showed their ability to suppress HIV-1 replication when the viruses co-infected CD4+T lymphocyte cultures. While the intrinsic mechanism of this finding still remains unclear, the inhibition of HIV-1 replication was observed only when a high multiplicity of infection (m.o.i.) of HHV-6 and a low m.o.i. of HIV-1 were used in dually infected cell cultures. By using a semiquantitative determination of HIV-1 cDNA by PCR, it appears that the inhibition begins in infected cell cultures and, once established, does not allow any further HIV-1 replication.
Subject(s)
Acquired Immunodeficiency Syndrome/virology , HIV-1/growth & development , Herpesviridae Infections/virology , Herpesvirus 6, Human/growth & development , Viral Interference , CD4-Positive T-Lymphocytes/virology , Cell Death , Cytopathogenic Effect, Viral , DNA, Viral/isolation & purification , HIV Core Protein p24/analysis , Herpesvirus 6, Human/classification , Herpesvirus 6, Human/genetics , Humans , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Virus ReplicationABSTRACT
We investigated by nested PCR the possible association of human herpesvirus 6 (HHV-6) and human papillomavirus (HPV) genomes in the cervixes of 109 women with normal and abnormal cytological smears. HPV DNA was detected in 8.33% of 24 women with normal cytologies and in 41.1% of 85 women with abnormal cytologies; the proportion of HPV DNA was directly related to the severity of the lesions. HHV-6 DNA was found in only one patient, who had a cytological pattern of koilocytosis. The HHV-6 genome was classified by restriction enzyme analysis as variant B. The study indicates that detection of the HHV-6 genome in the cervixes of women with a wide spectrum of gynecological complaints is a rare event and rules out the possible association between HHV-6 and HPV genomes in cervical cancer lesions.
