Immunodeficient nonobese diabetic-severe combined immunodeficiency-IL-2 receptor γ<sup>null</sup> mice were injected with human peripheral blood mononuclear cells, and subsequently injected with the CD39/CD73 antagonist αβ-methylene-ADP (APCP) (50 mg kg<sup>-1</sup> ) or saline for 7 days, or the AR antagonist caffeine (10 mg kg<sup>-1</sup> ) or saline for 14 days.