Abstract
BACKGROUND: Children show various degrees of vulnerability regarding HIV infection and disease progression. This disparity presents challenges for the follow-up of infected children. Here we investigated reasons behind this variability focusing on some host-related HIV genes. METHODS: We screened 570 Cameroonian children and adolescents, aged 1 to 19 years old. Among them, 137 were followed over 4 years, from 2010 to 2015. Upon signing a proxy consent, children and adolescents were classified according to their age, CD4 count, viral load and clinical symptoms as long-term non-progressors (LTNP), slow progressors (SP) and rapid progressors (RP). Their blood was collected every 6 months and used for biological and host genetic polymorphism analyses. Five genes were genotyped: Trim5α (R136Q), CCR5 promoter 59029G, CCR2-64I, SDF 3'A and CCR5-Δ32. Exposed non-infected (HEU) and unexposed HIV negative children (HNEU) were recruited as control groups. RESULTS: Among the 5 genes studied, the protective allele of Trim5α (R136Q) was present in all LTNP and in 72.34% and 2.56% of SP and RP, respectively (p<0.0001). The CCR5 promoter 59029G/G was also more present in LTNP and SP than in RP (p=0.02; p=0.04). The protective CCR2-64I homozygous genotype was almost absent in all groups, only the heterozygous genotype was present with a significant difference between RP vs SP (p=0.0001), and SP vs LTNP (p=0.0002). The CCR2-∆32 was completely absent either as homozygous or heterozygous genotype. It was a monomorphic allele. SDF 3'A was almost present as homozygous wild-type genotype in our study population and was associated neither to disease acquisition nor to disease progression. CONCLUSION: Among the 5 genes described in the study, Trim 5α (R136Q), CCR5 promoter 59029G and CCR2V64I alleles were associated to the progression of HIV infection in children and adolescents.