TACI mutations did not affect plasma BAFF concentrations (pg/ml)
measured by ELISA (A) or mature naive B cell expansion detected by
KREC analysis (B). Both were greater in CVID patients compared with
healthy controls. (C–F) CVID status, but not
TACI mutations, affected Treg frequency and function.
(C) Dot plots represent CD4+ gated
CD25hiFOXP3+ T cells of a healthy donor control and an
age-matched CVID patient with one TACI mutation. Scatter plots
reveal that decreased
CD4+CD25hiCD127loFOXP3+ Treg
frequency only correlated with CVID. yo, year-old. (D) Representative
histograms of Treg-mediated suppression of autologous and heterologous
CFSE-labeled Tresp cells on day 4.5 from a CVID patient and a healthy relative
both carrying a TACI mutation were compared with a healthy
control. Dashed lines display nonstimulated Tresp cells. The autologous and
heterologous suppressive activities of Tregs from healthy donor controls, healthy
carriers with a single TACI mutation, CVID patients with one or
two mutated TACI alleles, as well as CVID patients without
TACI mutations are summarized in E and
F, respectively. Statistical significance is indicated by an
unpaired Student’s t test.