Serum Levels of Collectins Are Sustained During Pregnancy: Surfactant Protein D Levels Are Dysregulated Prior to Missed Abortion.

About 15% of pregnant women undergo missed abortion (MA), wherein women do not experience cramping and vaginal bleeding. Dysregulation of the immune molecules and steroid hormones contribute to early pregnancy loss. Collectins- surfactant protein A (SP-A), surfactant protein D (SP-D), and mannose-binding lectin (MBL) are a group of innate immune molecules regulated by the steroid hormones. Reduced levels of SP-A and SP-D during the early gestation exhibited a significant association with the severe early onset preeclampsia. In order to determine the serum profile of collectins throughout the normal pregnancy and explore their predictive potential during the 8-12 weeks of gestation for MA, we examined a prospective cohort of pregnant women (n = 221). The serum levels of SP-A and SP-D were significantly downregulated in the normal pregnant women in all the three trimesters (n = 30) compared with the non-pregnant women (n = 20) and were not significantly different across the three trimesters. Fourteen of the women from the cohort underwent MA during the 14-20 weeks of gestation and exhibited a significant downregulation in the serum levels of SP-D during 8-12 weeks of gestation. A significant inhibition of the HTR-8/SVneo cell proliferation and migration in the presence of a recombinant fragment of human SP-D suggested the relevance of SP-D in placental development. We report here that the serum levels of SP-A, SP-D, and MBL are consistently maintained during pregnancy in the Indian cohort. Dysregulated serum levels of SP-D and P4/E2 ratio during the early first trimester may predict occurrence of MA.

Differential levels of surfactant protein A, surfactant protein D, and progesterone to estradiol ratio in maternal serum before and after the onset of severe early-onset preeclampsia.

PROBLEM: Preeclampsia (PE), a multifactorial disorder characterized by impaired placental development, elevated inflammatory response and dysregulated placental steroidogenesis. PE may be preventable if predicted early on. METHOD OF STUDY: The study evaluated the potential of immunomodulatory collectins, surfactant protein A (SP-A), surfactant protein D (SP-D), and mannose binding lectin (MBL), to predict PE before the disease onset, in a prospective study cohort of healthy pregnant women (n = 922). In addition, a cross-sectional study was conducted to determine the serum and placental profile of collectins in PE women after the disease onset (early-onset PE [EOPE], n = 33; late-onset PE [LOPE], n = 24); and controls [n = 75]. The serum profiles of estradiol (E2) and progesterone (P4) were evaluated to determine their correlation with collectins. RESULTS: In the prospective cohort, significantly decreased serum levels of SP-A, SP-D, P4/E2 ratio were observed in women who subsequently developed severe EOPE. Interestingly, after the disease onset, there was a significant increase in serum and placental levels of collectins in women with severe EOPE, whereas women with LOPE had significantly decreased levels of collectins. Serum P4/E2 ratio was significantly altered in severe EOPE and positively correlated with serum levels of SP-A and SP-D. CONCLUSION: Collectins are differentially expressed in the serum during progression of PE. Decreased serum levels of SP-A, SP-D, P4/E2 ratio and increased E2 during 10-20 weeks of gestation are novel plausible risk factors for early prediction of EOPE in Indian women.