, Eric Meffre and colleagues at Yale University evaluated B cell activation and tolerance development in healthy individuals and CVID patients with one or two mutated copies of
. The authors found that CVID patients with a single altered
allele maintained some residual B cell responsiveness that promoted development of autoantibodies, whereas individuals with 2 mutated copies of
have complete impairment of B cell responses, which likely prevents autoimmunity.
In the companion commentary, Antonia La Cava of the University of California Los Angeles suggests that targeting residual B cell activity in CVID patients that are heterozygous for TACI
mutations may provide clinical relief.