The characterisation of hyalocytes: the origin, phenotype, and turnover

• Published in: British journal of ophthalmology 2005-04, Vol.89 (4), p.513-517
• Main Authors: Qiao, H, Hisatomi, T, Sonoda, K-H, Kura, S, Sassa, Y, Kinoshita, S, Nakamura, T, Sakamoto, T, Ishibashi, T
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; bone marrow; bone marrow cells; Bone Marrow Cells - cytology; Bone Marrow Transplantation; Brain; Cell Differentiation; Cell Division; chimeric mice; Diabetic retinopathy; EGFP; enhanced green fluorescent protein; Eye and associated structures. Visual pathways and centers. Vision; FACS; Female; Flow cytometry; flow cytometry analysis; Fundamental and applied biological sciences. Psychology; Genotype & phenotype; GFAP; glial fibrillary acidic protein; Green Fluorescent Proteins - metabolism; hyalocyte; ILM; Immunophenotyping; inner limiting membrane; Laboratory Science - Extended Reports; Macrophages - immunology; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Electron; Microscopy, Electron, Scanning; Monocytes - immunology; Morphology; PBS; phosphate buffered saline; Physiology; propidium iodide; Rats; Rodents; scanning electron microscopy; SEM; Studies; TEM; Transgenic animals; transmission electron microscopy; transplantation; Transplantation Chimera; Vertebrates: nervous system and sense organs; Vitreous Body - immunology; Vitreous Body - ultrastructure
• ISSN: 0007-1161; 1468-2079
• DOI: 10.1136/bjo.2004.050658

Aim: To determine the characterisation of hyalocytes: the origin, phenotype, and turnover in the rodent. Methods: To characterise the ultrastructure and distribution of hyalocytes, transmission and scanning electron microscopy was performed in rat eyes. Immunophenotypical analysis was performed by either anti-ED1 or ED2 antibodies. To examine the origin of the hyalocytes, the chimeric mice were created and were used to transplant the bone marrow (BM) cells from enhanced green fluorescent protein (EGFP) transgenic mice. The turnover of hyalocytes was examined at 0, 4, 6, 7, and 12 months after BM transplantation. Results: Hyalocytes were distributed especially in the vitreous cortex and had an irregular shape with a spherical granule. Immunophenotypical studies demonstrated that most of the hyalocytes in rat eyes expressed ED2 but not ED1. In the chimeric mice, the hyalocytes were GFP negative right after BM transplantation. Interestingly, more than 60% of hyalocytes were replaced within 4 months and approximately 90% within 7 months after BM transplantation. Conclusions: The rodent hyalocytes were shown to express tissue macrophage marker, were derived from BM, and totally replaced within 7 months. These data provide the characterisation of hyalocytes in physiological conditions, especially their origin, distribution, and turnover, and may contribute to the better understanding of the pathogenesis of vitreoretinal disease.