Key genes related to these pathways (for example Cd8a for primary immunodeficiency and antibody production [59], Cd22, Cd79b, and Igj for the B cell receptor signaling pathway and antibody production [60,61,62], Cd8a for the T cell receptor signaling pathway and H2-Ob for Th17 cell differentiation [59], and Btla and H2-Ob for Th1 and Th2 cell differentiation and activation [63,64] were down-regulated in the infected Rag2-deficient mice. Here, JCHAIN is linked to inborn error of immunity.