The metabolism of different immunoglobulin classes in irradiated mice. V. Contribution of the gut to serum IgA levels in normal and irradiated mice.

Abstract

It was demonstrated in earlier publications that the acute and selective fall in serum IgA levels in irradiated mice was due to a specific failure to renew the plasma pool of this immunoglobulin. In the present work, it is shown that irradiation causes some reduction in the rate of biosynthesis of IgA, but that this phenomenon only partly accounts for the observed disturbance in the metabolism of IgA. This conclusion is based both on direct measurements on the rate of biosynthesis in vitro of IgA by the isolated small bowel wall of irradiated and normal C3H mice, and on immunohistological studies and plasma cell counts on the gut, spleen and lymph nodes of these animals.