Immunoglobulins A, G, and M in serum and in some secretions of monkeys (Macaca fascicularis syn. irus).

The purpose of this investigation was to study the distribution and levels of the following immunoglobulins, IgA, IgG, and IgM ,in sera and in some secretions of monkeys (M. fascicularis). IgG, IgA, and IgM were isolated from monkey serum and secretory IgA was separated from monkey milk by combined gel filtration and ion-exchange chromatography. These pure preparations served as standards to quantitate immunoglobulins in sera and secretions by single radial immunodiffusion. Antisera were raised in the rabbit against the pure immunoglobulins and also against the whole secretions to identify the immunoglobulins in immunoelectrophoresis. In common with humans, the major immunoglobulin in serum and amniotic fluid is IgG and the IgG/IgA ratio is greater than unity. In secretions IgA is the dominant immunoglobulin and the IgG/IgA ratio is less than 1. In general, the levels of immunoglobulins in the sera and secretions of monkeys paralleled the levels found in humans. No age-related increase in immunoglobulin levels was detected in the sera of monkeys.