NOS2 and infection: RNS appear to be dispensable for the innate immune defenses of mice against B. burgdorferi as mice treated with NG- L-monomethyl arginine to suppress RNS production or iNOS-deficient C3H/HeJ mice showed similar degrees of arthritis and spirochetemia as their untreated or wild-type counterparts following infection with B. burgdorferi (Seiler et al., 1995; Brown and Reiner, 1999).