p55 and p75 tumor necrosis factor receptor double KO and systemic lupus erythematosis

Gene expresion comperison of p55/p75 double knock and it control B57B6 identified a number of inflammatory genes and cytokines genes play important roles in this study. TNFa has both pro-inflammatory and immunoregulatory functions. Whereas a protective role for TNF administration in SLE-prone (NZB x NZW)F1 mice has been established, it remains uncertain whether this effect segregates at the individual TNF receptors (TNFR). We generated SLE-prone New Zealand Mixed 2328 mice genetically deficient in TNF receptor 1, in TNF receptor 2, or in both receptors. Doubly-deficient mice developed accelerated pathological and clinical nephritis with elevated levels of circulating IgG anti-dsDNA autoantibodies and increased numbers of CD4+ T lymphocytes, especially activated memory (CD44highCD62Llow) CD4+ T cells. We show that these cells expressed a Th17 gene profile, were positive for IL-17 intracellular staining by FACS, and produced exogenous IL-17 in culture. In contrast, immunological, pathological, and clinical profiles of mice deficient in either TNF receptor alone did not differ from those in each other or from those in wild-type controls. Thus, total ablation of TNFa-mediated signaling was highly deleterious to the host in the NZM 2328 SLE model. These observations may have profound ramifications for the use of TNF- and TNF receptor-antagonists in human SLE and related autoimmune disorders, as well as demonstrate, for the first time, the association of the Th17 pathway with an animal model of SLE. CD4+CD44highCD62Llow/neg spleen cells were isolated from 5-month-old female p55/p75 double knockout (DKO) NZM 2328 mice or C57BL/6 mice by depleting CD19+ B cells with magnetic beads (Dynal Biotech) followed by flow cytometry sorting . Total RNA was extracted from each sorted cell preparation using RNA STAT-60 isolation reagents (Tel-Test Inc. Friendswood, TX). First strand cDNAs were prepared from 250-500 ng total RNA of each sample using First Strand cDNA Kit (Fermentas Inc. Hanover, MD). Template cDNAs were characterized in technical quadruplicates using two different RT2 Profiler PCR Arrays: the mouse Th1-Th2-Th3 array and the Th-17 pathway PCR Array for Autoimmunity & Inflammation (SuperArray Bioscience, Fredrick, MD).