In contrast, the Hspa13 cKO mice had a reduction in PBs, PCs, and antibodies induced in vitro by LPS and in vivo by sheep red cells (SRCs) or 4-hydroxy-3-nitrophenylacetyl (NP)-immunization, and there were reduced numbers of autoantibodies and levels of proteinuria in both pristane-induced lupus and lupus-prone MRL/lpr mouse models. This evidence concerns the gene HSPA13 and systemic lupus erythematosus.