Several models of xenogeneic graft habe been developped but generally they use NSG or NOG (NOD SCID Gamma-/-) mice and not only SCID.
Personnally, I'm using NSG mice and I inject 30 millions of PBMCs intravenous in Sterile PBS. The mice develop graft versus host disease. I attached a reference talking about it.
Article Human peripheral blood leucocyte non‐obese diabetic‐severe c...