Transmitted drug resistance mutations and subtype diversity amongst HIV-1 sero-positive voluntary blood donors in Accra, Ghana

Abstract

Background: Detection of HIV-1 transmitted drug resistance (TDR) and subtype diversity (SD) are public health strategies to assess current HIV-1 regimen and ensure effective therapeutic outcomes of antiretroviral therapy (ART) among HIV-1 patients. Globally, limited data exist on TDR and SD among blood donors. In this study, drug resistance mutations (DRMs) and SD amongst HIV-1 sero-positive blood donors in Accra, Ghana were characterized.

Methods: Purposive sampling method was used to collect 81 HIV sero-positive blood samples from the Southern Area Blood Center and confirmed by INNO-LIA as HIV-1 and/or HIV-2. Viral RNA was only extracted from plasma samples confirmed as HIV-1 positive. Complementary DNA (cDNA) was synthesized using the RNA as a template and subsequently amplified by nested PCR with specific primers. The expected products were verified, purified and sequenced. Neighbour-joining tree with the Kimura's 2-parameter distances was generated with the RT sequences using Molecular Evolutionary Genetic Analysis version 6.0 (MEGA 6.0).

Results: Out of the 81 plasma samples, 60 (74%) were confirmed as HIV-1 sero-positive by INNO-LIA HIVI/II Score kit with no HIV-2 and dual HIV-1/2 infections. The remaining samples, 21 (26%) were confirmed as HIV sero-negative. Of the 60 confirmed positive samples, (32) 53% and (28) 47% were successfully amplified in the RT and PR genes respectively. Nucleotide sequencing of amplified samples revealed the presence of major drug resistance mutations in two (2) samples; E138A in one sample and another with K65R. HIV-1 Subtypes including subtypes A, B, CRF02_AG and CRF09_cpx were found.

Conclusion: This study found major drug resistance mutations, E138A and K65R in the RT gene that confer high level resistance to most NNRTIs and NRTI respectively. CRF02_AG was most predominant, the recorded percentage of subtype B and the evolutionary relationship inferred by phylogenetic analysis may suggest possible subtype importation. However, a more prospective and detailed analysis is needed to establish this phenomenon. The data obtained would inform the selection of drugs for ART initiation to maximize therapeutic options in drug-naïve HIV-1 patients in Ghana.

Keywords: Blood donors; HIV-1; Subtype diversity; Transmitted drug resistance.

Fig. 1

Percentage occurrence of HIV-1 subtypes in sequenced PR and RT genes. Figure 1 shows HIV-1 Subtype patterns in the PR and RT genes. PR and RT sequences were submitted online to the Stanford University HIV Drug Resistance Database (HIVdb). One (8%) was subtype A, 2 (17%) were subtype B and 9 (75%) were CRF02_AG. Of the 20 RT sequences, 2 (10%) were subtype A, 8 (40%) were subtype B, 9 (45%) were CRF02_AG and 1 (5%) was CRF09_cpx. Key: PR Protease, RT Reverse Transcriptase, CRF Circulating Recombinant Form

Fig. 2

Phylogenetic analysis of RT sequences of HIV-1 in the study. Figure 2 shows the phylogenetic analysis of RT sequences using Neighbor-joining tree with the Kimura’s 2-parameter distances generated with Molecular Evolutionary Genetic Analysis tool version 6.0 (MEGA6). Study samples were labelled with coloured squares (red, green, blue and black squares indicating different subtypes) and references labelled with accession numbers. Study sequences clustered around reference sequences from Nigeria, Cameroon, Kingdom of Saudi Arabia, Democratic Republic of Congo, United States of America, Peru, Uruguay and Britain. Key: CRF Circulating Recombinant Form