Study of the local graft versus host reaction in the rat. I. Evidences for a donor-related "rat effect".

The local graft versus host reaction (GVHR) observed in the hybrid F1 LBN rat was chosen to evaluate the immunologic effect induced by allogeneic transfusion of Brown Norway blood to the Lewis rat. Study of the kinetics of this GVHR with immunized as well as with nonimmunized cells shows an "individual rat effect" which is shown by a variability of the popliteal lymph node weight from one recipient to another. When spleen cells from different Lewis donors are pooled this effect disappears which indicates that it is related to the donor's rather than to the F1 recipient's cells. To even out variation between individual donors, cells from a number of donors should be pooled to allow better interpretation of experimental protocols using this GVHR.