Decreased expression of L-selectin on peripheral blood polymorphonuclear leukocytes in neonates with severe asphyxia

The expression of adherent leukocyte surface molecules, L-selectin (CD62L), and Mac-1 (CD11b/CD18) in peripheral blood polymorphonuclear leukocytes (PMNs) was studied in 48 neonates and 24 healthy adults using fluorescence flow cytometry. L-selectin expression was decreased significantly in neonates, especially those with severe asphyxia (n = 10) compared with adults. Mac-1 expression was significantly increased in neonates compared with adults, but did not differ between 24 normal neonates, 14 neonates with mild asphyxia, and 10 neonates with severe asphyxia. These results suggest that the magnitude of the decrease in L-selectin expression reflects the severity of asphyxia in neonates.