Predominance of CCR5 tropism in non-b HIV-1 subtypes circulating in Kisii County, Kenya
Introduction: The chemokine receptors CCR5 and CXCR4 are considered as the main receptors during HIV infection, replication, transmission and subsequent AIDS progression. CCR5 antagonists are drugs designed to inhibit viral entry by binding to these chemokine receptors. However, characterisation of HIV-1 co-receptor usage before rolling out of CCR5/CXCR4 antagonists has not yet been done in the country.
Objective: To determine the HIV-1 co receptor usage among HIV-1 infected individuals and predict possible use CCR5 antagonistic drugs.
Design: A cross sectional study Setting: Comprehensive HIV care clinics of Kisii Teaching & Referral Hospital, Kenya.
Methods: A total of seventy-two (72) blood samples were obtained from both drug naïve (32) and experienced (40) study participants. Viral DNA was extracted using QIAamp MinElute Virus kit and partial HIV-1 V3 region was amplified and directly sequenced. Coreceptor usage predicted using insilico Geno2pheno (coreceptor) with a false positive rate of 15%.
Results: Sixty-one individuals (77.8%) were infected with HIV-1 subtype A1, twelve (18.1%) HIV-1 subtype D and four (4.1%) were HIV-1 subtype C. CCR5-using variants were found in 52 (72.2%) while 20(27.8%) participants were infected with CXCR4–using variants. There was no significant difference in co-receptor usage a cross gender, HIV subtypes, disease staging or impact of treatment or CD 4 counts that was observed.
Conclusions and recommendation: The detected high level of circulating R5 strains suggests the likelihood of a successful implementation and use of CCR5 antagonists in Kenya where HIV-1 A1 is the most predominant.