Dominant interfering CARD11 variants disrupt JNK signaling to promote GATA3 expression in T cells

Several “primary atopic disorders” are linked to monogenic defects that attenuate TCR signaling, favoring T helper 2 (TH2) cell differentiation. Patients with CARD11-associated atopy with dominant interference of NF-?B signaling (CADINS) disease suffer from severe atopy, caused by germline loss-of-function/dominant interfering (LOF/DI) CARD11 variants. The CARD11 scaffold enables TCR-induced activation of NF-?B, mTORC1, and JNK signaling, yet the function of CARD11-dependent JNK signaling in T cells remains nebulous. Here we show that CARD11 is critical for TCR-induced activation of JNK1 and JNK2, as well as canonical JUN/FOS AP-1 family members. Patient-derived CARD11 DI variants attenuated wild-type CARD11 JNK signaling, mirroring effects on NF-?B. Transcriptome profiling revealed JNK inhibition upregulated TCR-induced expression of GATA3 and NFATC1, key transcription factors for TH2 cell development. Further, impaired CARD11-JNK signaling was linked to enhanced GATA3 expression in CADINS patient T cells. Our findings reveal a novel intrinsic mechanism connecting impaired CARD11-dependent JNK signaling to enhanced GATA3/NFAT2 induction and TH2 cell differentiation in CADINS patients. Overall design: RNA-seq profiling of wild-type and CARD11 KO Jurkat T cells stimulated for 2 hours with PMA and ionomycin in the absence or presence of inhibitors of JNK signaling (JNK inhibitor IX, JNK2 (MAPK9)-specific inhibitor; JNK-IN-8, JNK1/2 (MAPK8/9) inhibitor).