Graft vs Host reaction can be reduced by?

Ans. (a) Irradiation(Ref: Wintrobes 13th/704-705)Irradiation with a dose of 2,500 cGy at the center of the irradiation field, with a minimum dose of 1,500 cGy at any point in the field inhibits proliferation of donor lymphocytes but has no significant adverse effect on red cell, platelet, or granulocyte function.It should be noted that though the other options are also effectice in reducing the leukocytes but they do not completely deplete the lymphocytes and so can cause GVHD.