Ex vivo comparison of microbicide efficacies for preventing HIV-1 genomic integration in intraepithelial vaginal cells.

Abstract

Vaginally applied microbicides hold promise as a strategy to prevent sexual HIV transmission. Several nonspecific microbicides, including the polyanion cellulose sulfate, have been evaluated in large-scale clinical trials but have failed to show significant efficacy. These findings have prompted a renewed search for preclinical testing systems that can predict negative outcomes of microbicide trials. Moreover, the pipeline of potential topical microbicides has been expanded to include antiretroviral agents, such as reverse transcriptase, fusion, and integrase inhibitors. Using a novel ex vivo model of vaginal HIV-1 infection, we compared the prophylactic potentials of two forms of the fusion inhibitor T-20, the CCR5 antagonist TAK-778, the integrase inhibitor 118-D-24, and cellulose sulfate (Ushercell). The T-20 peptide with free N- and C-terminal amino acids was the most efficacious compound, causing significantly greater inhibition of viral genomic integration in intraepithelial vaginal leukocytes, measured by an optimized real-time PCR assay, than the more water-soluble N-acetylated T-20 peptide (Fuzeon) (50% inhibitory concentration [IC50], 0.153 microM versus 51.2 microM [0.687 ng/ml versus 230 ng/ml]; P<0.0001). In contrast, no significant difference in IC50s was noted in peripheral blood cells (IC50, 13.58 microM versus 7.57 microM [61 ng/ml versus 34 ng/ml]; P=0.0614). Cellulose sulfate was the least effective of all the compounds tested (IC50, 1.8 microg/ml). These results highlight the merit of our model for screening the mucosal efficacies of novel microbicides and their formulations and potentially rank ordering candidates for clinical evaluation.

• Authors: M Juliana McElrath, Lamar Ballweber, Andrew Terker, Allison Kreger, Polachai Sakchalathorn, Barry Robinson, Michael Fialkow, Gretchen Lentz, Florian Hladik
• Journal: Antimicrobial agents and chemotherapy (Antimicrob Agents Chemother) Vol. 54 Issue 2 Pg. 763-72 (Feb 2010) ISSN: 1098-6596 [Electronic] United States
• PMID: 19949052 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Anti-HIV Agents
• Benzothiepins
• HIV Envelope Protein gp41
• HIV Integrase Inhibitors
• Peptide Fragments
• TAK 778
• Enfuvirtide

Topics

• Adult
• Anti-HIV Agents (pharmacology, therapeutic use)
• Benzothiepins (pharmacology, therapeutic use)
• Cells, Cultured
• Enfuvirtide
• Female
• Flow Cytometry
• Genotype
• HIV Envelope Protein gp41 (pharmacology, therapeutic use)
• HIV Infections (drug therapy, prevention & control)
• HIV Integrase Inhibitors (pharmacology, therapeutic use)
• HIV-1 (drug effects, genetics, physiology)
• Humans
• In Vitro Techniques
• Microscopy, Confocal
• Peptide Fragments (pharmacology, therapeutic use)
• Polymerase Chain Reaction
• Virus Integration (drug effects, genetics)