Placental expression of cytokeratin 18 and serum levels of tissue polypeptide antigen in women with pregnancy-induced hypertension

Objective. We hypothesized that placental cytokeratin (CK) 18 expression an d serum levels of tissue polypeptide antigen (TPA), a surrogate marker for CK 18, are increased among women with pregnancy-induced hypertension (PIH). Methods. Serum levels of TPA were measured in 46 women with PIH and 46 cont rols, matched for gestational age and parity, using an immunoradiometric as say. Immunohistochemical detection of CK 18 was assessed in placental speci mens of 24 women with PIH and 20 controls. Results were cor related to clinical data. Results. Cytokeratin 18 expressi on was found in the syncytiotrophoblast of 7 of 20 (35%) and 18 of 24 (75%) placental specimens of controls and women with PIH, respectively (p = 0.00 8). Median serum levels of TPA in controls and women with PIH were 93.0 U/L (range: 12.5-281.6) and 154.2 Un (range: 37.3-496.6), respectively (p = 0.0 01). Serum levels of TPA significantly influenced the odds of presenting wi th PIH, as well as the odds of developing severe disease (p = 0.003, and p = 0.001, respectively). TPA values were significantly higher among women wi th severe PIH compared with women with mild PIH and controls, independent o f gestational age (p = 0.004). Among women with severe PIH. serum TPA was i nversely correlated with fetal birth weight (r = -0.3:p = 0.001). Conclusion. Cytokeratin 18 is overexpressed in the syncytiotrophoblast of w omen with PIH. Serum levels of TPA are elevated among women with PIH and co rrelate with disease severity and low fetal birth weight.