Absolute CD8+ T-Cell Count (Per Microliter)
This test measures the number of CD8+ T-cells in your blood, a type of immune cell that helps fight infections and cancer. CD8+ T-cells are part of your adaptive immune system and play a role in targeting and destroying infected or abnormal cells.
["CD8+ T-cells help protect your body by identifying and attacking harmful cells, so this count can indicate immune health or response to treatments."]
Key facts at a glance
- LOINC
- 17204-9
- Short code
- CD87
- Synonyms
- CD87 Cells NFr Bld
- Category
- chemistry
- Sample
- whole-blood
- Container
- EDTA (lavender-top) tube for flow cytometry
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–999 years
- Method
- Flow cytometry using fluorescently labeled monoclonal antibodies targeting CD87 (urokinase plasminogen activator receptor, uPAR)
- CPT
- 86356
- SNOMED
- 27070000
- Specimen volume
- 3-5 mL whole blood; minimum 1 mL for pediatric samples
- Stability
- Process within 24 hours of collection at room temperature (18-25°C); do not refrigerate as this may affect cell viability and marker expression
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 24–72 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may order this test if you have symptoms of immune disorders, such as frequent infections, unexplained fatigue, or if you’re undergoing treatment for conditions like HIV, cancer, or autoimmune diseases. It can also be used to monitor immune function before or after certain therapies.
What to Expect Before the Test
No special preparation is usually needed. You may have a small needle inserted into a vein in your arm to draw blood. This is typically done in a clinic or lab setting and takes about 5–10 minutes. Avoid strenuous activity or eating/drinking for 2–3 hours before the test if instructed.
What Happens During the Test
A healthcare professional will collect a blood sample from a vein in your arm. The blood will be sent to a lab, where it is analyzed to count your CD8+ T-cells. The results are usually available within 1–3 business days.
What the Results Mean
Results are reported as a count of CD8+ T-cells per microliter (µL) of blood. Lower-than-expected counts may suggest immune suppression, while higher-than-expected counts could indicate certain immune conditions or responses to treatments. Your provider will interpret the results in the context of your overall health.
Reference range
Reference values vary by laboratory; results typically reported as percentage of cells expressing CD87 or as cells per unit volume. Generally reported qualitatively or semi-quantitatively in clinical contexts.N/A
No special patient preparation required. Samples should be collected by standard venipuncture or capillary puncture techniques.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: CD8+ T-Cell Counts in Health and Disease
Short name
CD8+ T-Cell Count
Frequently asked questions
How often should I get this test?
What do abnormal results mean?
Can lifestyle changes affect this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy