CD3 Mutation Causes New Type of Immunodeficiency
CD3-zeta mutation discovered in boy with T-cell immunodeficiency
WEDNESDAY, May 3 (HealthDay News) -- A recessive mutation in a subunit of the T-cell receptor-CD3 complex can cause a previously unrecognized type of immunodeficiency, according to a case report in the May 4 issue of the New England Journal of Medicine.
Frederic Rieux-Laucat, Ph.D., of Hopital Necker in Paris, France, and colleagues examined the case of a boy with severe primary immunodeficiency. At 4 months of age, the boy presented with erythroderma, protracted diarrhea and pulmonary abscesses, and had numerous infections over the next two years.
The researchers found that the patient's T-cell counts were very low and that the patient had a homozygous mutation in CD3-zeta, one of the four subunits of the T-cell receptor-CD3 complex. The germline homozygous Q70X mutation was found in about 90 percent of T cells, while the remaining 10 percent had a germline Q70X mutation plus one of three somatic mutations on the other allele that allowed the production of close to normal levels of T-cell receptor-CD3 complex. The boy was treated with a bone marrow transplant from the mother, which corrected the immunodeficiency.
"In summary, we describe a form of T-cell immunodeficiency related to a recessive mutation of the CD3-zeta gene," Rieux-Laucat and colleagues conclude. "This observation adds to the reported variability in deficiencies of the various CD3 subunits."