Biologic Features of HIV-1 That Correlate with Virulence in the Host

Abstract

Individuals infected with the human immunodeficiency virus type 1 (HIV-1) may be asymptomatic or have AIDS-related complex or the acquired immuno deficiency syndrome (AIDS). Little is known about the factors that influence progression of infection to AIDS. In this study of isolates of HIV-1 obtained at intervals during the infection of four individuals, the development of disease was found to be correlated with the emergence of HIV-1 variants that were more cytopathic in vitro as the disease progressed and that replicated more efficiently in a wide variety of different human cells. The biologic properties of HIV-1 in vitro thus appear to reflect its virulence in the host. Further studies of such sequentially isolated viruses may lead to the identification of viral genes that govern pathogenesis.

Persistent infection of MT-4 cells by human immunodeficiency virus type 1 becomes increasingly likely with in vitro serial passage of wild-type but not nef mutant virus

“…Several studies have strongly implicated the viral envelope as a key determinant of cytopathogenicity (Sodroski et al, 1986;Cheng-Mayer et al, 1988;Kowalski et al, 1991). Generally, there are two mechanisms for the killing of cells in HIV-1 infection: the killing of single cells or syncytium formation.…”

Differential HIV-1 replication in neonatal and adult blood mononuclear cells is influenced at the level of HIV-1 gene expression

“…Most infected infants become symptomatic within the first few months of life, however, a subset of infants remains asymptomatic with immune abnormalities for years (2)(3)(4). In contrast to X4 viruses associated with AIDS progression in adults (5,6), rapidly progressing infected infants generally harbor R5 viruses associated with a high viral load (7,8). In contrast to HIV-1-infected adults where initial infection results in an acute retroviral syndrome with a high level of viremia followed by a set point (5,6), infected infants have a higher level of viremia than infected adults that is sustained over a long period (3,4).…”

“…In contrast to X4 viruses associated with AIDS progression in adults (5,6), rapidly progressing infected infants generally harbor R5 viruses associated with a high viral load (7,8). In contrast to HIV-1-infected adults where initial infection results in an acute retroviral syndrome with a high level of viremia followed by a set point (5,6), infected infants have a higher level of viremia than infected adults that is sustained over a long period (3,4). The pathogenesis of pediatric AIDS is not clearly understood but may be partially explained by relative immaturity of the immune system in early infancy.…”

HIV/AIDS: 30 Years of progress and future challenges

“…Early studies revealed differences among HIV isolates to replicate in macrophages versus T-cell lines that correlated with their cytopathology (e.g. syncytium formation) [13,14]. Generally, HIV isolates that grew in macrophages were nonsyncytium-inducing (NSI) and those in T-cell lines were syncytium-inducing (SI) viruses.…”