CD46 Genetic Variability and HIV-1 Infection Susceptibility.

Area of Science:

• Immunogenetics
• Virology
• Molecular Biology

Background:

• CD46 acts as a receptor for complement protein C3, crucial for adaptive immunity.
• CD46 genetic variations are linked to infectious and autoimmune disease susceptibility.
• HIV-1 utilizes CD46 to evade complement-mediated attacks, a strategy seen in other viral families.

Purpose of the Study:

• To investigate the association between CD46 gene variants and HIV-1 acquisition.
• To analyze the role of CD46 in susceptibility to HIV-1 infection via intravenous drug use and sexual transmission.

Main Methods:

• Genotyping of the rs2796265 single nucleotide polymorphism (SNP) in the CD46 gene.
• Utilizing allele-specific real-time PCR for genotyping.
• Performing a meta-analysis on European ancestry cohorts of HIV-1 infected and exposed but seronegative individuals.

Main Results:

• A meta-analysis revealed that the minor CD46 genotype (CC) was associated with significantly increased resistance to HIV-1 infection (OR = 0.2, p = 0.004).
• This protective genotype correlates with reduced CD46 expression levels.
• Alterations in the ratio of CD46 mRNA splicing isoforms were observed in individuals with the protective genotype.

Conclusions:

• The CD46 rs2796265 polymorphism, specifically the minor CC genotype, confers resistance to HIV-1 infection.
• This resistance is mechanistically linked to reduced CD46 expression and altered mRNA splicing.
• Findings highlight CD46 as a potential target for therapeutic or preventative strategies against HIV-1.