Janus kinase 3 (JAK3) deficiency: clinical, immunologic, and molecular analyses of 10 patients and outcomes of stem cell transplantation

• Published in: Blood Vol. 103; no. 6; pp. 2009 - 2018
• Main Authors: Roberts, Joseph L., Lengi, Andrea, Brown, Stephanie M., Chen, Min, Zhou, Yong-Jie, O’Shea, John J., Buckley, Rebecca H.
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 15.03.2004; The Americain Society of Hematology
• Subjects: B-Lymphocytes - cytology; B-Lymphocytes - immunology; B-Lymphocytes - metabolism; Biological and medical sciences; Cell Line, Transformed; Codon, Nonsense; DNA-Binding Proteins - metabolism; Female; Gene Deletion; Hematopoietic Stem Cell Transplantation; Humans; Immunodeficiencies; Immunodeficiencies. Immunoglobulinopathies; Immunopathology; Infant; Interleukin-2 - pharmacology; Janus Kinase 3; Killer Cells, Natural - immunology; Male; Medical sciences; Milk Proteins; Mutation, Missense; Phenotype; Phosphorylation - drug effects; Protein-Tyrosine Kinases - genetics; Protein-Tyrosine Kinases - metabolism; Reverse Transcriptase Polymerase Chain Reaction; Severe Combined Immunodeficiency - genetics; Severe Combined Immunodeficiency - immunology; Severe Combined Immunodeficiency - therapy; STAT5 Transcription Factor; Trans-Activators - metabolism; United States; Human; Immunopathology; Severe combined immunodeficiency; Enzyme; Transferases; Stem cell; Deficiency; Hematopoietic cell; Homograft; Treatment; Gene; Graft; Mutation; Protein-tyrosine kinase
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2003-06-2104

We found 10 individuals from 7 unrelated families among 170 severe combined immunodeficiency (SCID) patients who exhibited 9 different Janus kinase 3 (JAK3) mutations. These included 3 missense and 2 nonsense mutations, 1 insertion, and 3 deletions. With the exception of 1 individual with persistence of transplacentally transferred maternal lymphocytes, all infants presented with a T–B+NK– phenotype. The patient mutations all resulted in abnormal B-cell Janus kinase 3 (JAK3)–dependent interleukin-2 (IL-2)–induced signal transducer and activator of transcription-5 (STAT5) phosphorylation. Additional analyses of mutations permitting protein expression revealed the N-terminal JH7 (del58A) and JH6 (D169E) domain mutations each inhibited receptor binding and catalytic activity, whereas the G589S JH2 mutation abrogated kinase activity but did not affect γc association. Nine of the 10 patients are currently alive from between 4 years and 18 years following stem cell transplantation, with all exhibiting normal T-cell function. Reconstitution of antibody function was noted in only 3 patients. Natural killer (NK) function was severely depressed at presentation in the 4 patients studied, whereas after transplantation the only individuals with normal NK lytic activity were patients 1 and 5. Hence, bone marrow transplantation is an effective means for reconstitution of T-cell immunity in this defect but is less successful for restoration of B-cell and NK cell functions.