Mouse major histocompatibility class I gene expression begins at midsomite stage and is inducible in earlier-stage embryos by interferon

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 82; no. 8; pp. 2427 - 2431
• Main Authors: Ozato, K, Wan, Y.J, Orrison, B.M
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 01.04.1985; National Acad Sciences
• Subjects: Animals; Antibodies; ANTIGENE; ANTIGENOS; ANTIGENS; DESARROLLO EMBRIONARIO; DEVELOPPEMENT EMBRYONNAIRE; Embryo, Mammalian - immunology; Embryonic cells; EMBRYONIC DEVELOPMENT; Embryos; GENE EXPRESSION; Gene Expression Regulation - drug effects; Germ cells; Gestational Age; H-2 Antigens - genetics; HISTOCOMPATIBILIDAD; HISTOCOMPATIBILITE; HISTOCOMPATIBILITY; Histocompatibility antigens class I; IMMUNE RESPONSE; INTERFERON; Interferons - pharmacology; Messenger RNA; MHC class I genes; MICE; Mice, Inbred Strains; Pregnancy; RATON; REPONSE IMMUNITAIRE; RESPUESTA INMUNOLOGICA; RNA; RNA, Messenger - genetics; RNA, Messenger - metabolism; SOURIS
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.82.8.2427

To determine the timing of major histocompatibility complex class I gene expression during embryonic development, binding of anti-class I antibodies and appearance of class I gene transcripts were examined in mouse embryos from the egg-cylinder stage through day 16 of gestation. By using two series of monoclonal antibodies reactive with monomorphic and polymorphic determinants of class I antigens, it was found that cell-surface expression of the antigens becomes detectable at a low level only after midsomite stage on gestation day 10, at a time when embryos are developed beyond primordial organogenesis and have partial blood circulation. In agreement with the above finding, a low level of class I mRNA became detectable in day 9 and older embryos in blot hybridization. The level of class I transcripts in embryos at least to day 13 remained less than 1/50th that in adult spleen cells. Cells from head-fold stage embryos (gestation day 8), which otherwise do not have an appreciable amount of class I mRNA or surface antigens, begin to express a high level of antigens upon treatment with mouse α /β or γ interferon. This induction of class I antigen expression appears to be stage specific in that embryos in an earlier egg-cylinder stage (day 6) failed to express the antigens after interferon treatment. A possible role of interferons in activating class I genes during in vivo embryonic development is suggested.