Association between lymphocyte and monocyte subsets and cognition in children with HIV.

BACKGROUND: This study assesses the relationships between lymphocyte and monocyte subsets and intelligence quotient (IQ) scores in antiretroviral therapy (ART)-naive, HIV-infected Thai children without advanced HIV disease. FINDINGS: Sixty-seven ART-naive Thai children with CD4 between 15-24% underwent cognitive testing by Weschler intelligence scale and had 13 cell subsets performed by flow cytometry including naive, memory and activated subsets of CD4+ and CD8+ T cells, activated and perivascular monocytes and B cells. Regression modelling with log10 cell count and cell percentage transformation was performed.Median age (IQR) was 9 (7-10) years, 33% were male, CDC stages N:A:B were 1:67:31%, median CD4% and count (IQR) were 21 (18-24)%, 597 (424-801) cells/mm3 and HIV RNA (IQR) was 4.6 (4.1-4.9) log10 copies/ml. Most (82%) lived at home, 45% had a biological parent as their primary caregiver, and 26 (49%) had low family income. The mean (SD) scores were 75 (13) for full scale IQ (FIQ), 73 (12) for verbal IQ (VIQ) and 80 (14) for performance IQ (PIQ). Adjusted multivariate regression analysis showed significant negative associations between B cell counts and FIQ, VIQ and PIQ (p < 0.01 for all); similar associations were found for B cell percentages (p < 0.05 for all). CONCLUSIONS: High B cell counts and percentages were strongly associated with poorer FIQ, VIQ and PIQ scores. Prospective, long-term assessment of cell subsets and determination of relevant B cell subpopulations could help further elucidate associations between lymphocyte subsets and neurocognitive development.

Characteristics of lymphocyte subsets in HIV-infected, long-term nonprogressor, and healthy Asian children through 12 years of age.

BACKGROUND: There are limited data on the immune profiles of HIV-positive children compared with healthy controls, and no such data for Asian children. OBJECTIVES: To immunophenotype HIV-positive Asian children, including long-term nonprogressors (LTNPs), compared with age-matched healthy controls. METHODS: We used flow cytometry to analyze 13 lymphocyte and monocyte subsets from 222 untreated, HIV-positive children with 15% to 24% CD4(+) T cells and no AIDS-related illnesses and 142 healthy children (controls). Data were compared among age categories. Profiles from LTNPs (n = 50), defined as children ≥8 years old with CD4(+) T-cell counts ≥350 cells/mm(3), were compared with data from age-matched non-LTNPs (n = 17) and controls (n = 53). RESULTS: Compared with controls, HIV-positive children had lower values (cell count per mm(3) and percent distribution) for T(H) cells and higher values for cytotoxic T cells, with reductions in populations of naive T(H) and cytotoxic T cells, B cells, and natural killer (NK) cells. HIV-positive children had high values for activated T(H) and cytotoxic T cells. Compared with non-LTNPs, LTNPs had higher values of T(H) and cytotoxic T cells, naive and memory T-cell subsets, and B and NK cells. Surprisingly, counts of activated T(H) and cytotoxic T cells were also higher among LTNPs. LNTPs were more frequently male. CONCLUSION: Untreated, HIV-infected Asian children have immune profiles that differ from those of controls, characterized by low values for T(H) cells, naive T cells, B cells, and NK cells but high values for cytotoxic, activated T(H), and cytotoxic T cells. The higher values for activated T cells observed in LTNPs require confirmation in longitudinal studies.

Soluble CD163 and monocyte populations in response to antiretroviral therapy and in relationship with neuropsychological testing among HIV-infected children.

BACKGROUND: Monocytes play a central role in HIV neuropathogenesis, but there are limited data on monocyte subsets and markers of monocyte activation in perinatally HIV-infected children. OBJECTIVE: To determine the relationship between monocyte subsets, the sCD163 monocyte activation marker, and neuropsychological performance among perinatally HIV-infected children initiating antiretroviral therapy (ART). METHODS: ART-naïve children from the PREDICT study were categorised into two groups: those on ART for ≥24 weeks (ART group, n =201) and those untreated (no ART group, n =79). This analysis used data from the baseline and week 144 including sCD163 and frequencies of activated monocytes (CD14+/CD16+/HLA-DR+), perivascular monocytes (CD14+/CD16+/CD163+ and CD14low/CD16+/CD163+), and neuropsychological testing scores: Verbal and Performance Intelligence Quotient (VIQ and PIQ), Beery Visuomotor Integration (VMI) and Children's Color Trails 2 (CT2). RESULTS: Baseline demographic and HIV disease parameters were similar between groups. The median age was 6 years, CD4 was 20% (620 cells/mm3), and HIV RNA was 4.8 log10. By week 144, the ART vs the no ART group had significantly higher CD4 (938 vs 552 cells/mm3) and lower HIV RNA (1.6 vs 4.38 log10 copies/mL, P <0.05). sCD163 declined in the ART vs no ART group (median changes -2533 vs -159 ng/mL, P <0.0001). Frequencies of all monocyte subsets declined in the treated but not the untreated group (P <0.05). Higher CD14+/CD16+/HLA-DR+ percentage was associated with higher VIQ, Beery VMI and CT2 scores. Higher percentages of CD14+/CD16+/CD163+ and CD14low/CD16+/CD163+ were associated with higher CT2 and VIQ, respectively. CONCLUSION: ART significantly reduced sCD163 levels and frequencies of activated and perivascular monocytes. Higher frequencies of these cells correlated with better neuropsychological performance suggesting a protective role of monocyte-macrophage immune activation in perinatal HIV infection in terms of neuropsychological function.