Biological and biochemical characteristics of serum fraction effluent from xenografts and inhibiting leukocyte migration.

Serum effluent from the hyperacutely rejected rabbit-to-dog liver graft strongly inhibits migration of peripheral blood leukocytes. Fractionation of this serum on DEAE-Sephadex A-50 revealed the most active fraction to be that containing IgG. This finding supports our view that immune complexes formed during the hyperacute rejection of xenografts are mainly responsible for the inhibition of migration of peripheral blood leukocytes.