Tolerization of BWF1 lupus mice with pConsensus peptide results in a distinct gene signature in WBC, CD4+ and CD8+T cells: Role of Foxp3 and IFI202b in suppression of SLE (50.22)

Abstract

Abstract Systemic lupus erythematosus (SLE) is an autoimmune disease associated with autoantibodies, including IgG anti-DNA and immune complexes. Following tolerization with an artificial peptide (pCONSENSUS, pCons) that is based on anti-DNA IgG sequences containing MHC class I and class II T cell determinants, NZB/NZW F1 female (BWF1) mice develop CD4+CD25+ regulatory T cells and CD8+ Foxp3+ inhibitory T cells, both of which suppress anti-DNA Ig production. In this study, we analyzed 45,000 murine genes using Affymetrix Gene Chip 430, 2.0 arrays, in a comparison of total white blood cells (WBC), CD4, and CD8 spleen cell subsets from tolerized vs. non-tolerized mice. Results showed 448, 174 and 60 genes that were differentially expressed by at least two-fold in the two groups of mice. From the CD8+T cell arrays, we confirmed up regulation of several genes in cells from tolerized mice using real-time PCR. Increased expression (more than two-fold) in the CD8+Tcells from tolerized mice was repeatedly found for six genes: IFI202B, Bcl2, Foxp3, Trp-53, CCR7 and IFNar1. Silencing with siRNA of IFI202b and bcl2 abrogated the suppressive capacity of the tolerized CD8+T cells. In contrast, silencing of IFNar1 and CCR7 had no effect on the ability of the CD8+T cells to suppress autoantibody production. Further silencing of combination of multiple genes affected other genes in addition to silenced gene/genes in tolerized CD8+T cells. These data indicate the roles of IFI202b, Foxp3, bcl2, and further demonstrate that silencing of one gene or combinations may affect other genes and or their functions.