Diminished actin polymerization of neonatal neutrophils determined by a microvolume whole blood method.
To investigate the actin response to chemotactic stimulation of neonatal neutrophils, we developed a new procedure to measure neutrophil F-actin content directly in microvolume whole blood (100 microliters sample each test). Using this procedure, we compared neutrophil actin response to N-formyl-methyonyl-leucyl-phenylalanine (FMLP) between groups of normal neonate and adult volunteers. Relative F-actin content (FMLP/control ratio) of neonatal neutrophils is significantly lower than those of adult volunteers' neutrophils both at 30 sec (1.94 +/- 0.34 vs. 2.25 +/- 0.31; n = 16, p < 0.05, t test) and 60 sec (2.23 +/- 0.19 vs. 2.40 +/- 0.27; n = 16, p < 0.05, t test) after FMLP stimulation. These results provide new evidence of impairment of neutrophil actin response in the neonate, which may partially explain the observed chemotactic defect in neonatal neutrophils.
Chen
W Y
WY
Department of Pediatrics, Kaohsiung Medical College, R.O.C.
Lei
H Y
HY
Lu
C C
CC
D000199:Actins / Q000378:metabolism*; D000328:Adult; D002634:Chemotaxis, Leukocyte; D005434:Flow Cytometry; D006801:Humans; D007231:Infant, Newborn; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism
D000199:Actins; D011108:Polymers; D009240:N-Formylmethionine Leucyl-Phenylalanine