Murine cytomegalovirus retinitis during MAIDS: Susceptibility correlates with elevated intraocular levels of interleukin-4 mRNA.

Published

Journal Article

PURPOSE: To determine if murine cytomegalovirus (MCMV)-infected eyes of mice with murine acquired immunodeficiency syndrome (MAIDS) that are destined to develop MCMV retinitis display elevated intraocular levels of interleukin-4 (IL-4) mRNA when compared with uninfected eyes of mice with MAIDS and unmanipulated, uninfected, eyes of normal healthy mice. METHODS: Groups of C57BL/6 mice with MAIDS and normal C57BL/6 mice were infected uniocularly with MCMV by subretinal MCMV injection. IL-4 levels in individual spleens collected five days later from groups of MAIDS mice and normal mice were assessed by quantitative ELISA. MCMV-infected eyes and uninfected contralateral eyes from another group of mice with MAIDS were also collected at five days postinfection and individually subjected to competitive RT-PCR assay and real-time RT-PCR assay for detection and quantification of IL-4 mRNA. Unmanipulated eyes from normal C57BL/6 mice served as controls. RESULTS: IL-4 mRNA was detected at a level of 9.7 +/- 3.4 pg mRNA per 1000 ng total RNA in 100% of MCMV-infected eyes of mice with MAIDS by competitive RT-PCR assay, but could not be detected in any of the uninfected eyes of MAIDS mice. In comparison, the more sensitive technique of real-time RT-PCR assay detected copies of IL-4 cDNA in both MCMV-infected eyes and uninfected eyes of MAIDS mice. MCMV-infected eyes showed a 16-fold increase in the number of IL-4 cDNA copies when compared with uninfected eyes. Neither technique detected IL-4 mRNA in unmanipulated eyes of normal mice. As expected, spleen cells from mice with MAIDS expressed significantly greater levels of IL-4 when compared with spleen cells from normal mice. CONCLUSIONS: MCMV-infected mice with MAIDS exhibited an expected preferential activation of Th2 cells as determined by increased levels of IL-4 in spleen cells when compared with spleen cells of normal mice. MCMV-infected eyes destined to develop retinitis during MAIDS also showed increased levels of detectable IL-4 mRNA when compared with uninfected eyes of mice with MAIDS. It is therefore possible that IL-4 synthesis by Th2 CD4+ T cells during retrovirus-induced immunosuppression serves to inhibit the perforin cytotoxic pathway that subsequently allows susceptibility to MCMV retinitis during MAIDS.

Full Text

Duke Authors

Cited Authors

  • Dix, R; Cousins, S

Published Date

  • March 2003

Published In

Volume / Issue

  • 26 / 3-4

Start / End Page

  • 211 - 217

PubMed ID

  • 12815549

Pubmed Central ID

  • 12815549

International Standard Serial Number (ISSN)

  • 0271-3683

Digital Object Identifier (DOI)

  • 10.1076/ceyr.26.3.211.14902

Language

  • eng

Conference Location

  • England