Thank you for your question. We are not aware of any literature indicating that K562 cells do not express NKG2-D, however we will investigate it further based on your comment. We do not have any additional Western blot data available at this time for this mouse monoclonal, NKG2-D Antibody (5C6): sc-53501. However, we do have positive flow cytometry (FCM) data in CD8+ human peripheral blood leukocytes. We are also aware of a publication citing use of this antibody for immunoprecipitation and Western blot, please see PMID: 21816829 for details. In addition, there is another citation using this antibody specifically in K562 cells, please see PMID: 27057443 for details.