Double-negative T cells are non-ALPS-specific markers of immune dysregulation found in patients with aplastic anemia.

摘要

We read with interest the recent article by Dowdell and colleagues exploring somatic FAS gene mutations among patients with autoimmune lymphoproliferative syndrome (ALPS), a syndrome characterized by defective CD95 (Fas) cell surface-mediated apoptosis. In assigning the diagnosis of ALPS, demonstration of a population of peripherally expanded CD4~-/CD8~-, double-negative T lymphocytes (DNTs; > 1.5% of normal lymphocytes) that express alpha/beta T-cell receptors (alpha-beta TCRs), is widely considered a key laboratory criteria.As indicated by the authors, the pathogenic nature of DNT cells remains a matter of debate. Indeed, patients with rare autoimmune diseases, including systemic lupus erythematosus (SLE) and immune thrombocytopenic purpura (ITP), have demonstrated mild elevations, suggesting that DNTs may perhaps be more common among immune disorders.