Case Report: A Case of HIV Seroconversion in a High-Risk Individual after 35 Years of Resistance with a CCR5Δ32 Heterozygous Genotype.

Numerous studies have examined the factors contributing to the variation in disease progression among people living with HIV-1, identifying a range of genetic, immunologic and virologic factors that interact in a complex, multifactorial dynamic. However, investigating individual susceptibility to HIV-1 infection adds an additional layer of complexity. In this observational report, we focus on the case of a man (Case-2021) who previously remained HIV-1 negative despite 35 years of self-reported high-risk sexual behavior with other men while enrolled in the MACS/WIHS Combined Cohort Study (MWCCS). To understand why this individual stayed free of HIV-1 infection for so long and what led to his eventual seroconversion, we examined the available genetic, immunologic, and virologic laboratory data before and two weeks after his diagnosis of HIV-1 infection and initiation of antiretroviral therapy (ART). In addition, we looked into two other high-risk men from same group (HR-10) who have sex with men (MSM) enrolled in the MWCCS who seroconverted later in their enrollment. Furthermore, we performed similar laboratory tests to assess the effect of seasonal variations on blood biomarkers from the same clinical visit as Case-2021, including one individual who already was living with HIV-1 and another who has remained seronegative throughout their enrollment in the MWCCS. In conclusion, this Case-2021 observational report suggests that resistance to HIV-1 infection is likely multifactorial, involving high risk sexual behavior, HIV-1 variants, the genomic structure of the CCR5 receptor on CD4+ T cells, and age-related immune changes. Further study is needed to investigate both the genomic protective factors of CCR5 against HIV-1 infection and these age-related immune changes.