A Novel Cysteine Sulfinic Acid Decarboxylase Knock-Out Mouse: Immune Function (II)

Taurine deficient mice lacking cysteine sulfinic acid decarboxylase (CSAD KO) were developed for investigating the various physiological roles of taurine including the development of the brain and eye as well as immune function. Due to severe abnormalities of immune function in a taurine deficient cat, the immune function including adoptive and innate immunity in taurine-deficient mice have been studied. Previously we demonstrated that B cell function in CSAD KO was reduced in both females and males. However, T cell function was significantly reduced only in females. In this study, we have examined innate immunity using macrophage activation with LPS or/and IFN-γ and polymorphonuclear leukocytes (PMN) activation with phorbol myristate acetate (PMA). Pro- and anti-inflammatory cytokines including IL-6, TNF-α and IL-10 as well as nitric oxide (NO) were determined using ELISA and Griess reagent, respectively. Peritoneal macrophages were activated with 1 μg/mL of lipopolysaccharide (LPS) and/or 50 U/mL of IFN-γ. In addition, superoxide anion was measured using peritoneal PMN activated with PMA in the presence and absence of superoxide dismutase. Superoxide anion production in activated PMN from CSAD KO homozygotes (HO) was not significantly different from wild-type (WT) with and without 25 mM taurine. IL-10 and TNF-α production in both female and male CSAD KO were not significantly different. IL-6 and NO were significantly lower only in females as previously observed in Con A-activated cellular proliferation of splenocytes. Cytokine production with 10 mM of taurine was not different, indicating the reduction of NO and IL-6 in females may be due to the absence of the CSAD gene, not due to low taurine concentrations.These data indicate that some measures of innate immunity were altered in female CSAD mice.