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HelpOrder Code QNKS Natural Killer (NK)/Natural Killer T-Cell Subsets, Quantitative, Blood
Useful For
Quantitation of the major natural killer (NK)-cell subsets relative to total NK cells (NK cell subsets) or total lymphocytes (NK T cells)
Assessment in the following clinical contexts: HIV, primary immune deficiencies with NK cell defects, NK-cell lymphocytosis, solid-organ transplantation, immune reconstitution following bone marrow or hematopoietic cell transplantation
This test is not useful for diagnosis or classification of NK cell malignancies.
This test should not be used for assessing NK cell cytotoxic function.
Reporting Name
Quantitative NK/NKT SubsetsSpecimen Type
WB Sodium HeparinSpecimen Minimum Volume
0.2 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| WB Sodium Heparin | Ambient | 30 hours | GREEN TOP/HEP |
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | OK |
Reference Values
The appropriate age-related reference values will be provided on the report. Pediatric reference values are not available for patients younger than 7 years and therefore, interpretation will be based on the 7- to 17-year old ranges with appropriate cautionary statements in the interpretation.
Method Description
The absolute quantitation of natural killer (NK) subsets is performed as a 2-tube assay with BD Trucount tubes. Tube 1 provides the isotype control for CD56 and CD16 markers. A combination of antibodies directed against the following surface markers are used to identify the 4 major NK subsets as well as natural killer T cells. Whole blood is stained with the surface marker antibodies in the dark for 20 minutes, followed by red blood cells lysis for 10 minutes in BD FACS Lysing solution. Samples are analyzed on a BD FACS Canto II flow cytometer and data analysis is performed in FACS DIVA 8.0 software.(Unpublished Mayo method)
Day(s) Performed
Monday through Friday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
86356 x3
86359
86357
Method Name
Flow Cytometry
Ordering Guidance
This assay does not measure cell-surface or intracellular proteins on natural killer or natural killer T-cell subsets.
A minimum CD45 lymph count (as measured by flow cytometry in the laboratory) is required to report this test. If that requirement is not met (eg, patients with severe lymphopenia), the test will be canceled and an alternate test will be suggested (TBBS / Quantitative Lymphocyte Subsets: T, B, and Natural Killer [NK] Cells, Blood).
Shipping Instructions
Send specimen Monday through Thursday only. Specimen must arrive within 24 hours of collection and by 10 a.m. Central time on Friday.
Collect and package specimen as close to shipping time as possible. Ship specimen overnight.
Necessary Information
The ordering healthcare professional's name and phone number are required.
Specimen Required
Container/Tube: Green top (sodium heparin)
Specimen Volume: 3 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Additional Information: For serial monitoring, it is recommended that specimens are collected at the same time of day.