Homogeneous immunoglobulins in sera of rhesus monkeys after lethal irradiation and bone marrow transplantation.

The immunoglobulin pattern in the sera of lethally irradiated and bone marrow transplanted Rhesus monkeys was studied during the reconstitution of their immune system. All of the irradiated monkeys which survived longer than 30 days, and in which reconstitution of their immune system took place, also developed homogeneous immunoglobulins (HI) in their sera. These homogeneous, sometimes multiple, immunoglobulins were transient. However, they persisted frequently in the sera for several months. In two monkeys which were additionally immunized with a complex antigen (normal human serum), clear-cut M-components appeared in the serum about 10 days later. These HI of IgG class did not precipitate the antigen in immunodiffusion techniques; however, when passing the serum through an immunoadsorbent prepared from normal human serum, only the HI were specifically retained on the column and afterwards isolated by elution.