Characteristics of experimental autoimmune hypophysitis in rats: major antigens are growth hormone, thyrotropin, and luteinizing hormone in this model.
We produced experimental autoimmune hypophysitis (EAH) in rats and investigated its characteristics. Female Lewis rats were immunized by two injections with homologous pituitary homogenate and complete Freund's adjuvant. Blood was collected serially from the rats, and serum antibodies to pituitary antigens were examined. The rats were sacrificed 2 or 4 weeks after the final immunization, and histological examinations of the endocrine organs were carried out. Histological examination revealed slight, focal infiltration of mononuclear cells in the pituitary gland only in the rats immunized with the pituitary homogenate. Infiltration of mononuclear cells was not observed in the thyroid gland, pancreas, adrenal gland, or ovary. In the serological examination, antibodies to both cytosolic antigens and cytoplasmic particle antigens from the pituitary gland were detected by enzyme-linked immunosorbent assay (ELISA), and these antibody levels increased with time. Western blotting using the serum antibodies identified an immunoreactive protein of approximately 21.5 kDa among these antigens, and we confirmed that this protein was rat growth hormone (GH). Furthermore, antibodies to GH, thyrotropin (TSH), and luteinizing hormone (LH) were detected by ELISA. Antibodies to follicule stimulating hormone, prolactin, or adrenocorticotropin were not detected. These data suggest that several antigens from the pituitary gland are involved in EAH in rats, and that GH, TSH, and LH are major antigens among the pituitary antigens in this model.
Watanabe
K
K
Department of Laboratory Medicine, Osaka University Graduate School of Medicine, Suita, Japan.
Tada
H
H
Shimaoka
Y
Y
Hidaka
Y
Y
Tatsumi
K
K
Izumi
Y
Y
Amino
N
N
D000818:Animals; D001324:Autoantigens / Q000276:immunology*; D001327:Autoimmune Diseases / Q000276:immunology*; D004195:Disease Models, Animal; D005260:Female; D013006:Growth Hormone / Q000276:immunology; D007986:Luteinizing Hormone / Q000276:immunology; D010900:Pituitary Diseases / Q000276:immunology*; D010902:Pituitary Gland / Q000473:pathology; D010908:Pituitary Hormones, Anterior / Q000276:immunology*; D049590:Postpartum Period / Q000276:immunology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology*; D051381:Rats; D011917:Rats, Inbred Lew; D013972:Thyrotropin / Q000276:immunology
D001324:Autoantigens; D010908:Pituitary Hormones, Anterior; D007986:Luteinizing Hormone; D013972:Thyrotropin; D013006:Growth Hormone