Human platelets involvement in immune modulation of graft rejection in mice

A cell lysate consisting of human thrombocytes is able after a unique i.p. application in mice to prolonge significantly the survival time of skin allografts. A linear relation is existing between the dosis and the effect within a defined dosis area (100 to 300 x 10(6) Gpt). The correlation was proved by the application of cell lysates from 12 single donors (r = 0.575, P less than 0.05) as well as by the application of 5 differently diluted preparations produced from a concentrated total pool (r = 0.577). The fact is discussed that the protective clinical transplant effects occurring by pre-operatively administered blood transfusions may be due to the same principle of action.