Human secretory immunoglobulins. VI. Association of free secretory piece with serum IgA in vitro.

  • 1 August 1971
    • journal article
    • Vol. 21  (2) , 323-32
Abstract
In vitro complexing of native free secretory piece (SP) was relatively specific for serum IgA, but only a minor proportion of the molecules combined. Two types of aggregate with the molecular size of polymer IgA were formed. One was indistinguishable from native secretory IgA; it contained disulphide-linked SP and exhibited a closely packed quaternary structure with inaccessible I determinant. This determinant was exposed in the other type which apparently represented relatively loose complexes stabilized solely by noncovalent forces.