Annals of Laboratory Medicine

Korean Society for Laboratory Medicine (대한진단검사의학회)
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Natural Killer Cell Assays: Clinical Applications and Future Directions

  • Minjeong Nam (Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine) ;
  • Wooseok Park (Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine) ;
  • Hyun-Young Kim (Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine) ;
  • Duck Cho (Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine)
  • Received : 2025.08.27
  • Accepted : 2025.12.19
  • Published : 2026.05.01
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Abstract

Natural killer (NK) cells play critical roles in immune surveillance and homeostasis maintenance through cytotoxicity and cytokine release. The ability of NK cells to eliminate target cells without the need for prior antigen recognition or antibody involvement has drawn considerable attention for translational and clinical applications. As clinical applications continue to broaden, interest in NK cell assays has been growing markedly. This review provides an in-depth discussion of current clinical applications of NK cell assays, including NK cell phenotype, frequency, and functional activity assessments. This review further highlights the diagnostic potential of these assays in terms of hemophagocytic lymphohistiocytosis and potential NK cell biomarker candidates in diverse pathological contexts, such as cancer, infection, autoimmune diseases, and other diseases. By integrating clinical insights with technological advancements, NK cell assays can serve as valuable tools for disease diagnosis, prognosis, and therapeutic monitoring.

Keywords

Acknowledgement

This research was supported by the National Research Foundation of Korea (NRF), funded by the Korea Government (MSIT) (Grant Nos. RS-2023-00242443, RS-2024-00345126, and RS-2025-00519514), a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health and Welfare, Korea (Grant No. KH129441), and the Future Medicine 2030 Project of the Samsung Medical Center (Grant No. SMO1250091).

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