Gene therapy to induce cellular resistance to HIV-1 infection: lessons from clinical trials

Strategies for promoting adherence to antiretroviral therapy: a review of the literature

The success of antiretroviral therapy (ART) for HIV infection, though widespread and resounding, has been limited by inadequate adherence to its unforgiving regimens, especially over the long term. This article summarizes the literature on behavioral interventions to promote ART adherence and highlights some of the most recent and innovative research on patient education and case management, modified directly observed therapy, contingency management, interventions emphasizing social support, and novel technologies to promote awareness. Research in the area of adherence in pediatric HIV infection and in resource-constrained international settings also is considered. Although adherence interventions have been successful in experimental trials, they may not be feasible or adaptable given the constraints of real-world clinics and community-based settings. Implementation and dissemination of adherence interventions needs increased attention as ART adherence research moves beyond its first decade. We conclude with suggestions for incorporating research findings into clinical practice.

Expression of a modified form of CD4 results in the release of an anti-HIV factor derived from the Env sequence

We have studied the inhibitory effect of a CD4 chimera (CD4epsilon15) on HIV replication. This chimera is retained in the endoplasmic reticulum and traps the HIV envelope precursor gp160, preventing its maturation. Retroviral expression of the chimera strongly inhibited HIV replication even when it is expressed by only a minority of the T cell population. This protective effect on bystander nontransduced cells is mediated by a soluble factor that we identified as a fragment of HIV gp120 envelope protein and accordingly, we named this factor Env-derived antiviral factor (EDAF). Biochemical and immunoreactivity data show that EDAF is comprised of the gp120 C3-C5 regions and indeed, a recombinant protein bearing this sequence reproduces the anti-HIV properties of EDAF. Surprisingly, three tryptic peptides derived from EDAF are homologous but not identical with the corresponding sequences of the HIV isolate used to generate EDAF. We propose that EDAF results from an alternative intracellular processing of the Env protein provoked by its association to CD4epsilon15 and the selection of the best fitted Env protein sequences contained within the HIV isolate. The presence of EDAF improves the therapeutic potential of the CD4epsilon15 gene and it opens new possibilities for antiviral treatment and vaccine development.