title: Characterization of equine hyalocytes: their immunohistochemical properties, morphologies and distribution.
abstract: In horse, the characterizations of hyalocytes under the steady state are still unclear. Therefore, we investigated characterizations of hyalocytes in normal equine eyes by their immunohistochemical phenotype, histomorphology and distribution. Thirty-one eyes from 18 horses, divided into 4 groups (G) by age, were used: early (G1) and late gestation (G2) fetuses, 1- to 3-year-old (G3) and 8- to 24-year-old (G4) horses. Equine hyalocytes were histologically classified into 4 types, and they immunohistochemically expressed MHC II and CD163. Hyalocytes were detected on and/or around ciliary processes and pars plana in G2, G3 and G4, but were not located on retina and optic papilla. A significant increase in distribution was found between G2 and both G3 and G4, and the largest distribution was found at ciliary processes in these groups. Equine hyalocytes were characterized as residential ocular macrophage and MHC II antigen-bearing cell, accompanied by a pleomorphic appearance and located in the contiguous ciliary body. Our data provided characterizations of hyalocytes in normal equine eyes and may well contribute to improving the understanding of pathogenesis of equine ocular disease.
authors.affiliation: Department of Veterinary Pathology, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan.
authors.forename: Yuto
authors.initials: Y
authors.lastname: Sano
authors.forename: Kazuya
authors.initials: K
authors.lastname: Matsuda
authors.forename: Minoru
authors.initials: M
authors.lastname: Okamoto
authors.forename: Kazushige
authors.initials: K
authors.lastname: Takehana
authors.forename: Kazuko
authors.initials: K
authors.lastname: Hirayama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Taniyama
mesh_terms: D000367:Age Factors; D000818:Animals; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000662:veterinary; D006736:Horses / Q000033:anatomy & histology* / Q000196:embryology; D008285:Major Histocompatibility Complex / Q000276:immunology; D008297:Male; D014822:Vitreous Body / Q000166:cytology* / Q000648:ultrastructure