Rapid CommunicationSuccessful clinical treatment and functional immunological normalization of human MALT1 deficiency following hematopoietic stem cell transplantation

•The CARMA1-BCL10-MALT1 (CBM) complex regulates many immune responses.•Disabling mutations in MALT1 cause a novel human combined immunodeficiency.•Hematopoietic stem cell transplantation can be curative for human MALT1 deficiency.

MALT1 mutations impair normal NF-κB activation and paracaspase activity to cause a novel combined immunodeficiency. The clinical and immunological phenotype of MALT1 deficiency can be successfully treated with hematopoietic stem cell transplantation following reduced intensity conditioning.