IgG2 deficiency in ataxia-telangiectasia.

Abstract

ATAXIA-telangiectasia is a genetically linked multisystem degenerative disease with abnormalities in both humoral and cellular immune responses. IgA deficiency is common in this disorder1; IgE deficiency occurs,2 as does low IgG.3 , 4 We previously found that three patients with ataxia-telangiectasia had IgG2 deficiency.5 This investigation concerns IgG-subclass determinations in serum samples from 22 patients with ataxia-telangiectasia, 10 of whom had IgA deficiency.An imbalanced IgG-subclass pattern was noted. Very low or borderline-low serum IgG2 values were found in all 22 patients, serum IgG4 was undetectable in 19 of the 22, and the IgG1 levels were significantly increased (P<0.001 by Student's . . .