Deficiency of serum "pregnancy-associated" alpha 2-glycoprotein alpha 2-PAG): association with disease.

The serum concentrations of "pregnancy-associated" alpha 2-glycoprotein (alpha 2-PAG) were measured in 129 healthy women and 141 healthy men to establish a normal range, using a sensitive enzyme linked immunosorbent assay. In the normal population 2.8% of men and 5.4% of women had low serum alpha 2-PAG concentrations. Low concentrations occur, however, much more commonly in patients, particularly male patients, with certain diseases, including dermatitis herpetiformis (three of 12 or 25%) and urticaria (two of five or 40%). One female patient with absolute deficiency was also identified. In view of the recently confirmed association of alpha 2-PAG with IgA and the fact that alpha 2-PAG seems to have immunosuppressive properties, it seems likely that deficiency of alpha 2-PAG could result in the subject becoming sensitised to various dietary antigens. Interestingly, none of the 24 patients with IgA deficiency showed concomitant deficiency of alpha 2-PAG.