Poly (I:C) does not enhance alloimmunization to mHEL RBCs in the absence of a spleen. Splenectomized and nonsplenectomized mice were treated intraperitoneally with poly (I:C) or control PBS injections. Following treatment, mice were transfused with leukoreduced mHEL RBCs. Two weeks after transfusion, anti-HEL responses were measured using an anti-HEL IgG ELISA. This experiment was performed 3 times with similar results.