5. Detection of HIV DNA and HPV genotypes in the CD14+ fraction of anal cytology samples from HIV-positive human subjects

Abstract

Background: HIV-seropositive patients have a higher prevalence of other viral infections, including HPV, even while on anti-retroviral therapy. Anal infection with high-risk HPV genotypes can lead to anal dysplasia, which can progress to anal cancer. HIV and HPV can be contracted via sexual transmission; however, the interaction between these two pathogens and effect on the immune system are poorly understood. Since CD14 cells have been implicated in disease progression in other HIV-associated diseases, the objective of this study was to characterise CD14 cells from anal cytology specimens. Methods: Anal cytology samples were obtained from 14 HIV-positive patients enrolled in an anal dysplasia study. Samples were sorted for CD14 subsets. Following DNA extraction, HIV DNA copy was assessed by real-time PCR with primers/probes for β-globin and HIV gag genes. HPV DNA was amplified and genotypes identified using Roche’s LINEAR ARRAY HPV genotyping kit. Results: HIV DNA was detected in samples from 8 patients. Of those, 5 patients also tested positive for HPV genotypes. All 6 patients who tested HIV DNA-negative also tested HPV-positive. Due to low numbers, difference in HPV status relative to HIV DNA status was not statistically significant. HPV genotypes closely corresponded between CD14+ and CD14– fractions. Conclusions: Both HIV DNA and HPV genotypes can be detected from a single anal cytology specimen. Further studies are necessary to elucidate the significance of HPV genotypes detected in CD14+ fractions as well as the consequence of HIV and HPV coinfection in anal epithelia.