PD1 is decreased in blood cells of control children with higher serum levels of 1,25 (OH) Vitamin D3
We next wanted to analyze the role of 25(OH) VitD3 on Programmed cell death protein 1 (PD-1) in the cohort of preschool children. PD-1 is a protein on the surface of immune competent T cells that down-regulates T cell inflammatory activity.22,23Considering VitD3 serum levels lower than 20 ng/ml as low, we found that high VitD3 associated with decreased PD1 mRNA levels in blood cells of control but not asthmatic children (Fig 2d, e). We also saw a trend towards PD1 mRNA induction in asthmatic children with higher serum VitD3 levels.