Prevalence of C-C chemokine receptor type 5 tropism among human immunodeficiency virus 1–infected patients in South Korea

Objective: The discovery of two main coreceptors for human immunodeficiency virus (HIV), C-C chemokine receptor type 5 (CCR5), and C-X-C chemokine receptor type 4 has led to a better understanding of the interaction between HIV envelope and host cells, and development of new therapeutic approaches. The purpose of this study was to estimate the prevalence of CCR5 tropism among HIV-1–infected Koreans and identify the predictors for CCR5 tropism. Methods: We enrolled 250 HIV-1–infected subjects from four medical centers of three different cities in South Korea between April 2013 and May 2014. Genotypic assay for identifying coreceptor tropism of HIV-1 was performed with HIV RNA or HIV DNA. Nested polymerase chain reaction and population-based sequencing for the V3 region (HXB2 position 6225-7758) of the envelope were performed with HIV RNA or proviral DNA. Proviral DNA was used if the viral load of the subject was below 2000 copies/mL. Genotypic tropism was determined by a web-based bioinformatics tool (http://coreceptor.bioinf.mpi-inf.mpg.de/). Results: Among 250 individuals enrolled, only 143 subjects could be analyzed for genotypic tropism assay with HIV RNA or proviral DNA. The prevalence of CCR5 tropism was 69.2% (N = 99). We could not identify any significant clinical or epidemiological predictors for CCR5 tropism among enrolled subjects. Conclusions: The prevalence of CCR5 tropism in HIV-1–infected Korean individuals was 69.2%. Since we cannot predict coreceptor tropism by clinical factors, tropism assay should be performed before treatment with the CCR5 antagonist.