Developmental changes in soluble CD40 ligand

Objectives To determine if soluble CD40 ligand (sCD40L;.formally CD154) levels van, with age and to identify age-dependent ranges in healthy pediatric and adult populations. Study design sCD40L was measured in 25 neonates. 74 children (3 months-15 years of age) and 20 adults using air enzyme-linked immunosorbent assay. For age group comparisons, Mann-Whitney tests were performed. Correlation coefficients assessed relationships between plasma and serum sCD40L. Results Plasma sCD40L levels were higher in neonates than in all other age groups, (P <.001). All grouped pediatric plasma levels were significantly higher than in adults (P <.0001). There were no significant differences in plasma sCD40L between pediatric age groups. Serum levels were significantly higher in neonates than in any other age group (P <.0001). Pediatric and adult serum sCD40L levels were not significantly different. Conclusions Plasma sCD40L levels are highest at birth and remain higher than those in adults throughout childhood. Reasons for such developmental changes remain to be investigated. Age-appropriate reference ranges should be used when sCD40L is being evaluated in pediatric disorders.