Levels of major selenoproteins in T cells decrease during HIV infection and low molecular mass selenium compounds increase

Authors

Vadim Gladyshev, University of Nebraska-LincolnFollow
Thressa C. Stadtman, National Institutes of Health, Bethesda, MD
Dolph L. Hatfield, National Institutes of Health, Bethesda, MDFollow
Kuan-Teh Jeang, National Institutes of Health, Bethesda, MD

Date of this Version

February 1999

Comments

Published in Proc. Natl. Acad. Sci. USA Vol. 96, pp. 835–839, February 1999 Biochemistry. Permission to use.

Abstract

It has been observed previously that plasma selenium and glutathione levels are subnormal in HIV-infected individuals, and plasma glutathione peroxidase activity is decreased. Under these conditions the survival rate of AIDS patients is reduced significantly. In the present study, using ⁷⁵Se-labeled human Jurkat T cells, we show that the levels of four ⁷⁵Se-containing proteins are lower in HIV-infected cell populations than in uninfected cells. These major selenoproteins migrated as 57-, 26-, 21-, and 15-kDa species on SDS/PAGE gels. In our earlier studies, the 57-kDa protein was purified from T cells and identified as a subunit of thioredoxin reductase. The 26- and 21-kDa proteins were identified in immunoblot assays as the glutathione peroxidase (cGPX or GPX1) subunit and phospholipid hydroperoxide glutathione peroxidase (PHGPX or GPX4), respectively. We recently purified the 15-kDa protein and characterized it as a selenoprotein of unknown function. In contrast to selenoproteins, low molecular mass [⁷⁵Se]compounds accumulated during HIV infection and migrated as a diffuse band near the front of SDS/PAGE gels.