Use

Low numbers of natural killer (NK) cells are found in individuals who are susceptible to viral infections such as cytomegalovirus and varicella, highlighting the test’s role in assessing immune competence and surveillance against viral and malignant cells. Quest Diagnostics Nichols Institute performs this assay to measure NK cell levels including absolute lymphocytes, absolute NK cell counts, and percent NK cells as CD3–CD16+CD56+. Clinical interpretation supports evaluation of immune dysfunction or immune status monitoring.