【佳學基因檢測】免疫力基因檢測：CD3δ突變與免疫缺陷

免疫力大小基因檢測導讀：

Purpose of review 

The review describes advances in understanding the role of the CD3δ subunit in human T-cell development as deduced from a recently described human immunodeficiency. The review also compares CD3δ deficiency with other human CD3 subunit deficiencies and with corresponding animal models.

Recent findings 

In describing CD3δ deficiency in humans this review shows that patients with profound T-cell depletion, who present at 2-3 months with severe viral infection, lack CD3δ as a result of a mutation in the extracellular domain of this gene. The genetic aberration was discovered by comparing patients' and normal thymocytes, using mass gene screening with the microarray technique. In humans the absence of CD3δ results in a complete arrest in thymocyte development at the stage of double negative to double positive transition and the development of γδT-cell receptor-positive T cells is also impaired.

Summary 

Unlike patients with CD3γ or CD3ε deficiency who have a milder condition, patients with CD3δ deficiency present with severe lethal susceptibility to infections during early infancy. As expected, this profound immunodeficiency was cured with an allogenic bone marrow transplantation. In contrast to murine CD3δ^−/−, which retains a normal γδT-cell receptor-positive T-cell population and only partly affects the developmental transition of double positive to single positive thymocytes, CD3δ in humans appears to be more critically required for the development of both αβ and γδT-cell receptor-positive T-cell lineages. The studies also show for the first time that comparing relevant patients' with normal tissue using microarray technology can aid in the discovery of the genetic basis of inherited disorders.