Production and assay of dog, pig and goat heterologous anti-rabbit lymphocyte serum.

A series of skin allografts were carried out in rabbits receiving daily injections of heterologous antilymphocyte serum prepared in four goats, three dogs and three pigs. The most satisfactory prolongation of graft survival was obtained with goat anti-rabbit ALS, although only two of the goats utilized produced an effective anti-serum. A significant overall correlation was established between graft survival time and rosette inhibition titre, but not cytotoxicity or lymphagglutination titre. However, although ineffective sera were poor rosette inhibitors and immunosuppressive sera good inhibitors, a high titre was not always associated with a strong immunosuppressive activity, at least when mixing results obtained with goat and pig ALS.