CISH and tuberculosis: However, a remaining unresolved issue is why animals that lack CISH globally across all of these cell types demonstrate a type 2 bias.18 Humans with single nucleotide polymorphisms conferring reduced function of CISH show increased susceptibility to hepatitis B virus (HBV), bacteremia, tuberculosis (TB), and malaria53–55—observations consistent with our finding that CISH-deficient mice have increased susceptibility to Salmonella infection—but to our knowledge have not been reported to have allergic predilections.