Quantitative analysis of syncytium-inducing and non-syncytium-inducing virus in patients infected with human...

Area of Science:

• Virology
• Immunology
• Infectious Diseases

Background:

• Human Immunodeficiency Virus type 1 (HIV-1) infection leads to progressive immunosuppression.
• HIV-1 exhibits diverse biological properties, including syncytium-inducing (SI) and non-syncytium-inducing (non-SI) phenotypes.
• The clinical implications of different HIV-1 tropisms, particularly in advanced immunosuppression, require further elucidation.

Purpose of the Study:

• To compare CD4+ cell counts and viral loads between patients infected with SI HIV-1 and non-SI HIV-1.
• To investigate the correlation between virus titer and CD4+ cell count in patients with SI and non-SI HIV-1.

Main Methods:

• Cross-sectional study of 75 HIV-1-infected patients with moderate to advanced immunosuppression.
• Quantification of HIV-1 viral load using infectious units per 10(6) CD4+ lymphocytes.
• Determination of SI HIV-1 titers using a quantitative MT-2 cell assay.

Main Results:

• Patients with SI HIV-1 had significantly lower CD4+ cell counts (145 vs. 278 cells/µL) compared to non-SI HIV-1 patients.
• Viral titers were approximately 10-fold higher in patients with SI HIV-1 (398 vs. 39 infectious units/10(6) CD4+ lymphocytes).
• A significant inverse correlation was observed between SI virus titer and CD4+ cell count (r = -0.67) in patients with SI HIV-1.

Conclusions:

• Syncytium-inducing HIV-1 strains are associated with more severe immunosuppression and higher viral loads.
• The tropism of HIV-1, specifically the presence of SI variants, is a critical factor influencing disease progression and CD4+ cell depletion.
• Identifying SI HIV-1 may have prognostic value and inform therapeutic strategies in advanced HIV-1 infection.