Within and between race differences in lymphocyte, CD4+, CD8+ and neutrophil levels in HIV-uninfected children with or without HIV exposure in Europe and Uganda.
BACKGROUND
Racial immuno-haematological differences have been reported in children but to date have not been well quantified.


OBJECTIVE
To investigate differences in haemato-immunological markers over age between children born and living in Europe and Uganda.


METHODS
HIV-uninfected children living in Uganda (n = 1633) with cross-sectional data. Black (n = 604) and white children (n = 1355) living in Europe, both with prospective data. The children born in Europe were HIV-uninfected but born to HIV-infected mothers and were included in the European Collaborative Study (ECS).


METHODS
Patterns and levels of total lymphocyte (TLC), CD4+, CD8+ counts and CD4% were visualised by smoothers (a line representing the weighted average of all measurements over age by study group). Differences between groups were quantified using age-standardised Z-scores for individual TLC, CD4+ and CD8+ counts in uni- and multivariate regression models.


RESULTS
In infancy, TLC, CD4+ and CD8+ counts were lower in Ugandan than black European children; neutrophil counts were similar. Thereafter, only neutrophil counts were lower in Ugandan children. To assess within-race differences, we compared Z-scores of ECS children born to Ugandan mothers with those of Ugandan children. Levels of all four markers were lower in Ugandan children at all ages. In Ugandan children, CD4+ counts were 0.5985 Z-score (p < 0.001) and neutrophil counts 0.3872 Z-score (p < 0.001) lower than in European children born to Ugandan mothers.


CONCLUSIONS
There are differences in levels of haemato-immunological markers in children with comparable genetic backgrounds, suggesting that environmental factors such as nutrition and exposure to micro-organisms might have important effects on the developing immune system.
Bunders
Madeleine
M
Centre for Paediatric Epidemiology, Institute of Child Health, University College, London, UK.
Lugada
Eric
E
Mermin
Jonathan
J
Downing
Robert
R
Were
Willy
W
Thorne
Claire
C
Newell
Marie-Louise
ML
D000375:Aging / Q000276:immunology; D044383:Black People; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005060:Europe; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1; D006801:Humans; D007231:Infant, Newborn; D007958:Leukocyte Count; D008231:Lymphopenia / Q000276:immunology; D008297:Male; D009504:Neutrophils / Q000276:immunology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D011446:Prospective Studies; D012727:Sex Characteristics; D014454:Uganda; D044465:White People