Background: Some long-term non-progressors (LTNPs) have decreasing CD4+ T cell counts and progress to AIDS. Exploring which subsets of CD4+ T cell decreasing and the determinants associated with the decay in these patients will improve disease progression surveillance and provide further understanding of HIV pathogenesis.
Methods: Twenty-five LTNPs infected with HIV by blood products were classified as decreased (DG) if their CD4+ cell count dropped to < 400 cells/μL during follow-up or as non-decreased (non-DG) if their CD4+ cell count was ≥400 cells/μL. Laboratory and clinical assessments were conducted at 6 consecutive visits to identify DG characteristics.
Results: The LTNPs were infected with HIV for 12 (IQR: 11.5-14) years, and 23 were classified as the B' subtype. Six individuals lost LTNP status 14.5 (IQR: 12.5-17.5) years after infection (DG), and the CD4+ T cell count decreased to 237 (IQR: 213-320) cells/μL at the latest visit. The naïve CD4+ T cell count decrease was greater than that of memory CD4+ T cells [- 128 (IQR: - 196, - 107) vs - 64 (IQR: - 182, - 25) cells/μL)]. Nineteen individuals retained LTNP status (non-DG). At enrolment, the viral load (VL) level (p = 0.03) and CD8+CD38+ percentage (p = 0.03) were higher in DG than non-DG individuals. During follow-up, viral load and CD8+CD38+ percentage were significantly increased and negatively associated with CD4+ cell count [(r = - 0.529, p = 0.008), (r = - 0.476, p = 0.019), respectively]. However, the CD8+CD28+ percentage and B cell count dropped in DG and were positively correlated with CD4+ T cell count [(r = 0.448, p = 0.028), (r = 0.785, p < 0.001)].
Conclusion: Immunological progression was mainly characterized by the decrease of naïve CD4+ T cell in LTNPs infected with HIV by blood products and it may be associated with high HIV RNA levels.
Keywords: Blood products; High HIV RNA levels; Immune activation; LTNPs; naïve CD4+ T cell count diminishing.