Primary T-cell immunodeficiency with functional revertant somatic mosaicism in CD247.
نویسندگان
چکیده
To the Editor: T lymphocytes detect antigens with the T-cell receptor (TCR) composed of a variable heterodimer (either ab or gd), 2 invariant heterodimers (CD3gε and CD3dε), and an invariant homodimer (CD247 or zz). Because of the crucial role of TCR signaling in thymic selection, mutations in TCR, CD3, or CD247 selectively impair T-cell development, albeit to different degrees: deficiency of CD3d or CD3ε, but not of CD3g or CD247, causes severe T-cell lymphopenia. Their clinical outcome is also disparate, because CD3g deficiency does not require urgent transplantation. Thus, TCR immunodeficiencies display a range of phenotypes and careful differential diagnosis is essential for appropriate therapy. We describe an infant born to consanguineous parents with early-onset chronic cytomegalovirus infection, severe immunodeficiency, and extremely low surface TCR levels. Her immunologic characterization at age 11 months is summarized in Table E1 in this article’s Online Repository at www.jacionline.
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عنوان ژورنال:
- The Journal of allergy and clinical immunology
دوره 139 1 شماره
صفحات -
تاریخ انتشار 2017