Human placenta constitutively produces interleukin-8 during pregnancy and enhances its production in intrauterine infection

• Published in: Biology of reproduction Vol. 47; no. 2; pp. 220 - 226
• Main Authors: SHIMOYA, K, MATSUZAKI, N, TANIGUCHI, T, KAMEDA, T, KOYAMA, M, NEKI, R, FAJI, S, TANIZAWA, O
• Format: Journal Article
• Language: English
• Published: Madison, WI Society for the Study of Reproduction 01.08.1992
• Subjects: Biological and medical sciences; Blotting, Northern; Cells, Cultured; Chorioamnionitis - metabolism; Early stages. Segmentation. Gastrulation. Neurulation; Embryology: invertebrates and vertebrates. Teratology; Enzyme-Linked Immunosorbent Assay; Female; Fundamental and applied biological sciences. Psychology; Humans; Immunohistochemistry; Interleukin-8 - genetics; Interleukin-8 - metabolism; Placenta - chemistry; Placenta - cytology; Placenta - metabolism; Pregnancy - metabolism; RNA, Messenger - analysis; RNA, Messenger - genetics; Trophoblasts - metabolism; Pregnancy; Human; Immunohistochemistry; Chorioamnionitis; Placenta; Fetal membrane; Cytokine; Biosynthesis; Interleukin 8
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1095/biolreprod47.2.220

Interleukin-8 (IL-8) exerts unique chemotactic and activating activity on neutrophils. To address the significance of IL-8 in the fetoplacental unit during pregnancy, we cultured human placental explants that had been obtained by vaginal delivery, Caesarean section, or artificial abortion and then measured the IL-8 titer in the culture supernatants by enzyme immunoassay (EIA). Chorionic tissue from the first trimester produced a significant amount of IL-8 (2.2 +/- 0.4 ng/ml/10 mg, n = 5), while placentae in the second trimester (8.3 +/- 1.6 ng/ml/10 mg, n = 7) or at term (9.2 +/- 0.7 ng/ml/10 mg, n = 29) produced significantly higher amounts of IL-8. The presence or absence of labor did not affect the amount of placental IL-8 production. However, placentae with chorioamnionitis (25.2 +/- 1.6 ng/ml/10 mg, n = 9) showed significantly higher IL-8 production than those without chorioamnionitis (p less than 0.0001). Northern blot analysis of IL-8 mRNA expression demonstrated a constant level during pregnancy with or without chorioamnionitis, indicating the possibility that the major site of regulation of IL-8 synthesis in the placenta is posttranscriptional. Immunohistochemical analysis of first and third trimester placental tissues with rabbit anti-IL-8 antibody revealed the IL-8 producing cells to be trophoblasts and macrophage-like cells. IL-8 produced by the placental cells might contribute to potentiation of the immunocompetence of placental cells against bacteria invading the fetoplacental unit.