Lymphocyte stimulation assay utilizing newborn heel skin puncture blood samples

A micromethod for the study of lymphocyte stimulation using small volumes of blood obtained by heel skin or fingertip puncture is described. Heel skin puncture samples from 15 full term newborns and venous blood samples from 6 newborns gave very similar results. A study of paired venous blood and fingertip puncture samples from 5 normal adults and 2 children with severe combined immunodeficiency (SCID) showed no significant differences between lymphocyte responses of samples taken from these sites. The responses of adults were significantly lower than those of the full term newborns, while the responses of the SCID patients were markedly depressed. Lymphocyte stimulation studies using blood samples obtained by heel skin or finger puncture provide a useful method for detection of defects in cellular immunity in young infants.