Arylsulfatase-A in umbilical cord blood: gestational age and mode of delivery do not influence enzyme activity.

The possibility of using umbilical cord blood for transplantation in several enzyme deficiencies has received increasing attention because of the availability of cord blood, the reduced incidence of post-transplantation complications, such as graft-versus-host disease and the possible accomplishment of good corrective results following transplantation, even in cases of greater HLA disparity. The use of hematopoietic stem cells from unrelated donors is even more highly recommended for the treatment of inherited enzyme deficiencies, because it might reduce the risk of the transplanted cells originating from a carrier of the defect, which might have an inadequate corrective ability. Our study was designed to elucidate whether the gestational age and mode of delivery influences the arylsulfatase-A activity in the umbilical cord blood. Enzyme activities proved to be similar in the four populations studied (full-term normal spontaneous vaginal delivery, full-term caesarean section, preterm normal spontaneous vaginal delivery and preterm caesarean section). Therefore, umbilical cord blood samples seem to be suitable for transplantation in metachromatic leukodystrophy, regardless of gestational age and mode of delivery. Moreover, our results are the first published data on normal values for arylsulfatase-A activity in human umbilical cord blood.

Natural killer cell cytotoxicity is deficient in newborns with sepsis and recurrent infections.

UNLABELLED: We investigated natural killer (NK) cell cytotoxicity in healthy preterm and full-term newborns in comparison to adults, to elucidate the possible role of delivery mode in influencing the NK activity and to evaluate the NK activity in severe neonatal pathological conditions such as bacterial sepsis and recurrent infections. NK cell cytotoxicity was investigated using a 4 h 51Cr release assay with K562 cells as targets expressed as percentage kill in the following study groups: full-term normal spontaneous vaginal delivery (n = 55), full-term caesarean section (n = 51), preterm normal spontaneous vaginal delivery (n = 34), preterm caesarean section (n = 28), bacterial sepsis (n = 15), recurrent neonatal infections (n = 8) and healthy adults aged between 22-42 years (n = 89). NK activity for the normal newborns was determined in paired cord and 2-4 day-old neonate blood. The NK cell cytotoxicity in healthy newborns was significantly lower than in adults (P < 0.01). Prematurity was associated with a significant decrease in NK cell activity compared to full-term neonates (P < 0.05). The mode of delivery did not influence the NK cytotoxicity. In sepsis and recurrent infections, a dramatic decrease in NK cell cytotoxicity was seen related to healthy newborns (P < 0.01). CONCLUSION: Natural killer cell cytotoxicity is deficient in both neonatal sepsis and recurrent infections.