Mixed lymphocyte reaction

• mix irradiated MHC^b APCs with MHC^a T cells, which we expect to respond to foreign MHC

• add ³H-thymidine and see if helper T cells proliferate in the presence of this foreign MHC. this tests for viability of MHC class II

• then, add ⁵¹Cr-labeled target cells and observe whether T cells kill these target cells. this tests for viability of MHC class I

• this test can be used, for example, to see if donor is going to attack the recipient and cause graft-versus-host disease (GVHD)

• when a bone marrow transplant is performed, we want the donor cells not to be stimulated in either of these reactions. if we can meet this criteria, then we will lower the chance of GVHD

• note that when we are treating leukemia, we might desire a graft-versus-tumor effect. this is because we don’t want any of the recipient’s cancerous marrow to proliferate. on the other hand, when we are fixing SCID kids with BMT, all we want to do is to make sure they produce normal T and B cells, and we don’t need this graft-versus-tumor effect

Category: Pathology Notes