B. Effect of USP44 on USP7 levels. HEK293T cells were transfected with MYC-FOXP3. Cells also received combinations of FLAG-USP7 and varying doses of pLVX-USP44 encoding plasmids. FOXP3 was immunoprecipitated using anti-MYC, and immunoblots were analyzed using anti-FLAG, anti-USP44 or anti-MYC antibodies. 