The human immunodeficiency virus tat gene enhances replication of human herpesvirus-6.
Human herpesvirus-6 (HHV-6) can enhance the cytopathic effects of human immunodeficiency virus type 1 (HIV-1) in cells doubly infected by HIV-1 and HHV-6. HHV-6 enhances transcription of the HIV-1 long terminal repeat, and several HHV-6 trans-activator genes have been identified. Since HIV-1 and HHV-6 have similar cellular tropism, and since HIV-1 trans-activates other herpesviruses, a reciprocal interaction between the two viruses is possible. Interactions between HIV-1 and HHV-6 were analyzed in human umbilical cord blood (CB) lymphocytes and in a T-cell line by transfection and infection experiments. CB cells dually infected with HIV-1 and HHV-6 showed an increase in HHV-6 infectious titer, an increase in HHV-6-specific immediate early RNA, and an increase in HHV-6 protein synthesis. Similarly, T-lymphocyte cells transfected with the entire HIV-1 proviral genome displayed an increase in HHV-6. When T-cells were transfected with a plasmid containing the HIV-1 tat gene under control of the simian virus (SV40) promoter and infected with HHV-6, higher levels of HHV-6 proteins and infectious virus were detected. Therefore, the presence of HIV-1 gene products, such as tat, can lead to an activation of HHV-6 expression. Since HHV-6 is cytopathic, its activation by HIV-1 may accelerate the depletion of CD4+ T-cells in infected individuals.
Sieczkowski
L
L
Department of Neurology, University of Miami School of Medicine, Florida 33101, USA.
Chandran
B
B
Wood
C
C
D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers; D015756:Genes, tat; D015497:HIV-1 / Q000235:genetics*; D015654:Herpesvirus 6, Human / Q000502:physiology*; D006801:Humans; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics; D013601:T-Lymphocytes / Q000821:virology; D014775:Virus Activation / Q000235:genetics / Q000502:physiology; D014779:Virus Replication
D017931:DNA Primers; D012333:RNA, Messenger