Human immunoglobulin D in colostrum, saliva and amniotic fluid.

An antiserum raised to a partially purified preparation of secretory IgA isolated from human colostrum was shown to contain antibodies directed against human IgD. The inferred presence of IgD in the human colostrum was confirmed and also its association with antibody activity, as demonstrated by the presence of anti-E. coli antibodies. IgD was also shown to be present in whole saliva, parotid saliva and amniotic fluid, but could not be detected in jejunal juice.