Current HIV Research - Volume 7, Issue 2, 2009

We focus on the role of Vpr in inducing DNA double-strand breaks (DSBs) in the host cell. Based on the summarized findings of Vpr-induced DSBs and the finding of Vpr in the plasma of HIV-1-positive patients, we discuss the roles of Vpr in viral infection, especially viral infection of resting macrophages. We also describe the possible involvement of Vpr in non-AIDS-defining cancers, which represent an emerging crisis in HIV Read More

The human immunodeficiency virus-1 (HIV-1) Vpr protein plays multiple roles in HIV-1 replication. In early infection, Vpr provides help in the nuclear localization of pre-integration complex. Subsequently, Vpr induces cell cycle arrest of infected cells at G2/M phase. Cell cycle arrest facilitates higher rate of viral gene transcription. Vpr is also capable of activating transcription of viral and heterologous genes. Vpr induces apopto Read More

HIV viral protein r (Vpr) exerts a variety of cellular effects, including modulation of transcription and cytokine production, apoptosis, and cell cycle arrest. Vpr induces these affects by mechanisms that include inhibition of NFkappaB activation, inducing mitochondrial injury, and promoting proteasomal degradation of cellular factor(s) leading to cell cycle arrest. Murine models have provided invaluable contributions to our u Read More

The replication of human immunodeficiency virus type 1 (HIV-1) in non-dividing cells, such as terminally differentiated macrophages, critically depends on the import of the viral pre-integration complex (PIC) into the nucleus. Vpr, one of the accessory gene products of HIV-1, plays a key regulatory role in PIC nuclear import in macrophages, although its role in the PIC entry mechanism remains to be clarified. Here, we su Read More

Viral protein R (Vpr) is a 14kD, 96 amino acid accessory protein of the HIV virion that has been demonstrated to have important functions in the viral replication cycle including, among others, the induction of cell cycle arrest and apoptosis in rapidly proliferating cells, which results in immune dysfunction in infected individuals. Several investigators have studied the potential use of the apoptosis inducing and cell cycle arrest eff Read More

The HIV-1 Vpr protein is a viral accessory protein that plays a number of important roles during HIV infection. The activities of Vpr are numerous and include the induction of apoptosis, the modulation of cell cycle arrest, as well as control of viral transcription. Study of HIV clones lacking Vpr in vitro and analysis of HIV variants isolated from longterm nonprogressors in vivo highlight the importance of Vpr for viral replication as w Read More

Pre-mRNA splicing is a critical step in gene expression for metazoans. Several viral proteins regulate the splicing of pre-mRNAs through complex interactions with the host cell RNA splicing machinery. Here, we focus on a novel function of HIV-1 Vpr, which selectively inhibits cellular and viral pre-mRNA splicing via interactions with components of the spliceosome complex. This review discusses our current knowledge of how R Read More

HIV-1 exploits the cellular machinery to replicate in the host cells by targeting a wide range of host factors at different stages of its life cycle. HIV-1 also induces detrimental effects in the infected and uninfected bystander cells resulting in dysregulation including interference in immune effector functions. The latter is specifically linked to the immune evasion strategies of the virus. In addition to the essential roles of structural pro Read More

Human immunodeficiency virus type 1 (HIV-1) is engaged in dynamic and antagonistic interactions with host cells. Once infected by HIV-1, host cells initiate various antiviral strategies, such as innate antiviral defense mechanisms, to counteract viral invasion. In contrast, the virus has different strategies to suppress these host responses to infection. The final balance between these interactions determines the outcome of the vi Read More

Vpr, incorporated into the HIV-1 virion, shows multiple activities including nuclear transport of the preintegration complex to the nucleus, activation of the transcription, cell cycle arrest at the G2/M transition and induction of apoptosis. Vpr controls many host cell functions through a variety of biological activities and by interaction with cellular biochemical pathways. Nuclear import of Vpr may be due to its interaction with nucle Read More

Placental cytokine balance may be critical for the control of mother-to-child transmission (MTCT) of HIV. We assessed whether the type and duration of antiretrovirals used for prevention of HIV-1-MTCT modified the inflammatory cytokine profile. We investigated the levels of cytokine expression in the placentas of 61 HIV-1-infected women who received zidovudine (ZDV) plus single dose nevirapine (SD-NVP) or ZDV onl Read More

Some deficient genetic polymorphisms of the innate immune system have been correlated to a higher susceptibility to different infections, especially in immunocompromised patients. The possible association between an increased incidence of pneumococcal bacteremia in HIV-infected patients, and deficient polymorphisms of the mannose-binding lectin (MBL), MBL-associated serine protease 2 (MASP-2), and toll-like rec Read More

To study the prevalence of Delayed HIV Diagnosis (DHD) and its associated risk factors, to evaluate the effect of DHD on virological and immunological responses to HAART and to estimate the impact of DHD on all-causes mortality. Prospective cohort of 2, 564 HIV-positive HAART-naive subjects attending 19 hospitals in Spain, 2004-2006. Estimations were made by logistic regression and survival analyses by Cox re Read More

To explore the hypotheses that HIV-1 infected patients receiving suppressive antiretroviral therapy believe that they cannot transmit their virus, that this translates to increasing rates of unprotected anal intercourse and new infections, and that sexual practice may be influenced by the HIV-1 serostatus of one's sexual partner. We developed a Bernoulli model for HIV-1 transmission amongst a cross-sectional cohort of 119 HIV- Read More

The study goal is to identify predictors of HIV infection late detection in an European city with increased immigration, and determine the effects of HAART era in HIV infection detection. We used Barcelona city AIDS registry (1987-2006). Late testers were those diagnosed of AIDS defining illness within less than 3 months from time of testing positive for HIV infection. Independent variables were: date of birth, sex, country of origin Read More

Nucleoside Reverse Transcriptase Inhibitors (NRTIs) used for the treatment of HIV-1 inhibit the replication of mitochondrial DNA (mtDNA), which may contribute to severe mitochondrial toxicity including lipodystrophy, through the inhibition of polymerase gamma (POLG). Polymorphisms of POLG could explain the variation in mitochondrial toxicity in HIV-1-infected patients. We explored the relationship between selected poly Read More