Common variable immunodeficiency at the end of a prospering decade: towards novel gene defects and beyond

Purpose of review Patients with a primary antibody deficiency of unknown cause are usually allotted the diagnosis of common variable immunodeficiency (CVID), thus creating a genetically, immunologically, and clinically highly heterogeneous study population, that focuses the attention of many clinicians and researchers worldwide. The purpose of this review is to highlight the most important publications of the past year with an emphasis on novel findings in genetics and the immunophenotype of CVID. Recent findings New gene defects associated with a CVID phenotype have been described in BAFF-R, CD81, and CD20 in single consanguineous families. The CD21(low) B-cell subpopulation in CVID has been intensively characterized by us and other groups and is now better understood leaving their true nature and origin however still obscure. Further immunophenotypic analysis of T and B cells in large CVID patient cohorts revealed subgroups with signs of severely disturbed cellular immunity. Several studies investigated the status of regulatory T cells in CVID and found them to be reduced in numbers and impaired in function. Previous findings of impaired TLR function in CVID were confirmed and further extended. Summary Within the past decade, basic and clinical research on CVID has been boosted up by the discovery of the first gene defects and the systematic immunological classification by phenotypic and functional studies. The challenge for the next 10 years is not only the continuation of this ongoing work but also the translation of this acquired knowledge into the clinic and new therapeutic strategies.