Prolongation of skin allografts after oral application of ALS in rats

THE potency of anti-lymphocytic serum (ALS) in prolonging skin allografts has been well investigated. Four different routes of administration are being used: intravenous¹, intraperitoneal², intramuscular ³ and subcutaneous⁴. Every route has its own advantages and disadvantages from the immunological and clinical point of view and these have been discussed elsewhere^5,6. Oral application of ALS was never tried because it was assumed that intact proteins like gamma globulins are enzymatically metabolised before they pass through the intestinal wall. But we shall demonstrate, that even oral application of ALS can prolong the survival time of skin allografts.