title: Suppression of lymphocyte proliferation by ovarian cavity fluid from the viviparous fish Neoditrema ransonnetii (Perciformes; Embiotocidae).
abstract: As the fetus expresses paternal major histocompatibility complex molecules, viviparous vertebrates require sophisticated mechanisms to modulate maternal immunology to ensure successful pregnancy. We anticipated that ovarian cavity fluid (OCF) is likely to feature significantly in the modulation of ovarian cavity immunology. Consequently, we examined the effects of OCF upon leukocyte function in Neoditrema ransonnetii. OCF did not affect phagocytosis or superoxide production by phagocytes. However, OCF suppressed lymphocyte proliferation induced by ConA almost completely. As OCF contained PGE(2) at high levels during late pregnancy, we also investigated the effect of PGE(2) upon lymphocyte expansion. PGE(2) exhibited negative effects upon lymphocyte mitogenesis in a dose-dependent manner (10-1000 ng/ml). PGE(2) significantly suppressed lymphocyte proliferation when present at levels equivalent to that seen in OCF (30.2 +/- 16.1 approximately 185.4 +/- 107.4 ng/ml). Data indicate that PGE(2) is one of the key modulatory molecules of the maternal immune system ensuring successful pregnancy in this viviparous species.
authors.affiliation: School of Marine Biosciences, Kitasato University, Ofunato, Iwate 022-0101, Japan. df06004z@st.kitasato-u.ac.jp
authors.forename: Erina
authors.initials: E
authors.lastname: Saito
authors.forename: Osamu
authors.initials: O
authors.lastname: Nakamura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamada
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Tsutsui
authors.forename: Tasuku
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D005260:Female; D008214:Lymphocytes / Q000502:physiology*; D010053:Ovary / Q000502:physiology*; D010473:Perciformes / Q000502:physiology*; D052286:Viviparity, Nonmammalian / Q000502:physiology*