Our report indicates decreasedpercentage of CD16+CD69+NKG2D+ NK cells, low IFN-γlevels in the supernatant of NK cell cultures, decreased NKcell proliferation and reduced NK cell cytotoxic activityin DLBCL patients compared to the healthy donors in theabsence plasma-derived exosome of DLBCL patients.This could become the foundation of new therapeuticagent developments to target the NK cell activation andNK cell cytotoxicity. The gene discussed is KLRK1; the disease is diffuse large B-cell lymphoma.