Human cytomegalovirus infection in a retinoblastoma cell line in vitro

• Published in: Graefe's archive for clinical and experimental ophthalmology 1998-12, Vol.236 (12), p.945-949
• Main Authors: KUMANO, Y, LAYCOCK, K. A, HOOK, K. K, PEPOSE, J. S, STUART, P. M
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blotting, Western; Cytomegalovirus - physiology; Flow Cytometry; Follow-Up Studies; Galactosides - biosynthesis; Galactosides - genetics; Genes, Immediate-Early - genetics; Genes, Viral - genetics; Humans; Immunoenzyme Techniques; Lac Operon - physiology; Medical sciences; Ophthalmology; Retinal Neoplasms - metabolism; Retinal Neoplasms - pathology; Retinal Neoplasms - virology; Retinoblastoma - metabolism; Retinoblastoma - pathology; Retinoblastoma - virology; RNA, Viral - analysis; Tumor Cells, Cultured - virology; Tumors and pseudotumors of the eye, orbit, eyelid, lacrimal apparatus; Viral Proteins - analysis
• ISSN: 0721-832X; 1435-702X
• DOI: 10.1007/s004170050185

The focus of these studies was to determine whether the Y79 human retinoblastoma cell line could function as a good in vitro model system for studying human cytomegalovirus (HCMV) infection. Y79 cells were exposed to an HCMV mutant carrying a LacZ gene, and the resulting beta-galactosidase expression in infected cells was assessed by flow cytometry. The extent to which the three classes of viral gene products immediate early, early, and late proteins - were expressed was analyzed by immunohistochemical staining and Western blotting. Infected Y79 cells were also co-cultivated on human foreskin fibroblast (SF cell) cultures to recover virus. Infection of Y79 cells with the virus resulted in beta-galactosidase expression as detected by flow-cytometric analysis. Immunohistochemical staining revealed that a portion of Y79 cells expressed antigens reactive to monoclonal antibodies against immediate early, early, and late HCMV proteins. The 43-kDa early gene product was also detected by Western blotting. Infected Y79 cells co-cultivated on SF cell cultures yielded infectious foci, which turned blue following X-gal staining, demonstrating productive HCMV infection in the Y79 cells. These results demonstrate that while HCMV can productively infect Y79 cultures, it does so in a highly inefficient manner, leading these authors to conclude that this cell line does not provide a particularly good model system to study HCMV infection.