Evidence for a suppression of apoptosis in early postnatal life.
BACKGROUND
In fetal life the rates of proliferation and apoptosis are high. We studied if the rate of apoptosis decreases after birth, by measuring the soluble (s) forms of Fas-Fas ligand and Tumor necrosis factor receptor 1 (TNFR1)-TNF-alpha which attenuate apoptosis.


METHODS
Blood was drawn from the umbilical cord and from a peripheral vein on day 1 and 4 of life in 35 infants and sFas, sFas ligand, sTNFR1 and sTNF-alpha were determined by enzyme immunoassays. Data were analyzed by paired t-test and Pearson's correlation analysis.


RESULTS
sFas and sTNF increased significantly from birth to day 4 of life (p=0.033 and p<0.0001 respectively), while sTNFR1 increased significantly from birth to day 1 of life (p<0.0001) followed by a significant decrease on day 4 of life (p<0.0001). The levels of sFas and sTNF-alpha on day 1 correlated with those on day 4 (r=0.677, p<0.0002 and r=0.525, p<0.007 respectively). sFAS ligand was not detectable in any specimen.


CONCLUSIONS
The increasing concentrations of the soluble molecules, sFas, sTNF-alpha and sTNFR1 might indicate that apoptosis may be downregulated in early postnatal life.
Malamitsi-Puchner
A
A
Neonatal Division, Second Department of Obstetrics and Gynecology, University of Athens, Soultani 19, Aretaieion Hospital, GR-10682 Athens, Greece.
Sarandakou
A
A
Tziotis
J
J
Trikka
P
P
Creatsas
G
G
D017209:Apoptosis / Q000502:physiology*; D015536:Down-Regulation / Q000502:physiology*; D053222:Fas Ligand Protein; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006801:Humans; D007231:Infant, Newborn / Q000097:blood / Q000502:physiology*; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood; D011247:Pregnancy; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D019014:fas Receptor / Q000097:blood
C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D019014:fas Receptor