Partial Interferon-gamma Receptor Deficiency in Patients with Disseminated Tuberculosis. |
Jung Hye Hwang, Won Jung Koh, Shin Hye Lee, Eun Joo Kim, Eun Hae Kang, Gee Young Suh, Man Pyo Chung, Hojoong Kim, O Jung Kwon |
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. wjkoh@smc.samsung.co.kr |
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Abstract |
BACKGROUND Interferon-gamma (IFN-gamma) is essential in the immune response to mycobacterial infections, and a complete or partial deficiency in the IFN-gamma receptor 1 (IFNgammaR1) or the IFN-gamma receptor 2 (IFNgammaR2) have been reported to confer susceptibility to a disseminated infection with nontuberculous mycobacteria. However, similar mutations in the IFN-gamma receptor have not been specifically examined in the patients with clinical tuberculosis. METHODS: This study searched for mutations in the IFN-gamma receptor gene that resulted in a partial IFN-gamma receptor deficiency in six patients with disseminated tuberculosis. The previously identified IFNgammaR1 and IFNgammaR2 coding regions were sequenced after amplification. RESULTS: There was no partial IFNgammaR1 deficiency including a homozygous recessive missense mutation causing an amino-acid substitution in the extracellular domain of the receptor (I87T) and a hotspot for small deletions (818delT, 818del4, 818insA) found in any of the patients. In addition, a partial IFNgammaR2 deficiency of the homozygous missense mutation (R114C) was not found in any of the patients. CONCLUSION: Genetic defects causing a partial IFN-gamma receptor deficiency were not identified in our patients with disseminated tuberculosis. |
Key Words:
Tuberculosis, Genetic predisposition to disease, Interferon receptors, Point mutation |
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