Tissue Polypeptide Specific Antigen and Soluble Fas During Normal Pregnancy and Early Life

Background: Intrauterine fetal development is characterized by increased rates of proliferation and apoptosis, while both these processes may be attenuated post-natally.

Aim: Tissue polypeptide specific antigen and sFas serum concentrations were determined during pregnancy and post-natally, in order to evaluate their alterations during these crucial periods.

Materials And Methods: Forty-seven healthy pregnant women, their full-term newborns and 35 healthy adults (controls) were included in the study. Markers were measured: (a) in maternal serum (MS), during the 1st, 2nd, 3rd trimester and at the 1st stage of labor; (b) in the umbilical cord (UC), during the 2nd stage of labor; (c) in neonatal serum in the 1st (IN) and 5th (5N) day after birth; and (d) in controls.

Results: The serum TPS concentrations in MS increased significantly with gestational age, being higher in the 3rd trimester and labor, than those in controls (p < 0.001). TPS values were significantly lower in the UC, compared to those in MS (p < 0.001), while they were markedly elevated in IN, compared to MS and UC (p < 0.001), and subsequently decreased in 5N (p < 0.001), remaining higher, than those in the controls (p < 0.001). Serum sFas concentrations in the MS depended significantly on gestational age (p < 0.001), being significantly lower in the first trimester, than those in the second (p < 0.003), the third (p < 0.03), in labor and controls (p < 0.005). sFas concentrations in the UC were significantly lower than in MS and controls (p < 0.001), while they increased significantly in 5N samples (p < 0.01).

Conclusion: Our results demonstrate: (a) a higher apoptosis rate in the first trimester of pregnancy, possibly affecting maternal immuno-tolerance, followed by a down-regulation during the post-natal period; (b) a progressively increased proliferation from the first trimester to parturition, reflecting the fetal and placental growth and development, that seems to be thereafter moderated.