Impact of breastfeeding duration on T-lymphocyte subsets at 6 months of age.

<p><b>A,</b> Gating strategy for T-cell subset delineation. CD4+ and CD8+ T-cell subsets were defined within total CD3+ T cells, and subsequently dissected using CD45RO and CCR7 into naive, central memory, CD45RO+ effector memory (TemRO) and CD45RO- effector memory (TemRA) T cells. The reference depict density plots of total lymphocytes and were used to set the gates accordingly. <b>B,</b> Backtransformed CD4 and CD8 cell counts (cells/μL) at 6 months of age according to different breastfeeding duration categories (reference category is never). Categories of breastfed children contain both partial and exclusively breasted children. <b>C,</b> The estimated backtransformed regression line reflects CD4 and CD8 cell counts (cells/μL) at 6 months of age, per month increase in breastfeeding duration. *, P<0.05.