Interleukin-2 receptor alpha (CD25) in serum/plasma
This test measures the level of CD25, a protein involved in immune cell signaling, often found in blood. It helps assess immune system activity and certain immune-related conditions.
["CD25 levels can indicate immune activation or autoimmune disorders."]
Key facts at a glance
- LOINC
- 29596-4
- Short code
- CD25-IHC
- Synonyms
- CD25 Ag Tiss Ql ImStn
- Category
- chemistry
- Sample
- serum
- Container
- Sterile container with 10% neutral buffered formalin for tissue fixation; paraffin-embedded tissue block preferred for archival IHC analysis
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- immune-stain
- CPT
- 88342
- SNOMED
- 395128002
- Specimen volume
- Tissue biopsy specimen of adequate size (minimum 0.5 cm) in formalin or as paraffin-embedded block; fresh frozen tissue acceptable for some protocols
- Stability
- Formalin-fixed tissue: Indefinitely at room temperature in 10% neutral buffered formalin; paraffin block: Indefinitely at room temperature; cut sections: Stable for 1-2 weeks at 2-8°C before mounting for staining
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 48–96 hours
- Order
- routine
What Is CD25 Used For?
CD25 is primarily measured to evaluate immune responses, particularly in conditions where immune cells become overly active. It may be used in diagnosing or monitoring autoimmune diseases, infections, or certain cancers that involve immune dysregulation.
How Is the Test Performed?
A blood sample is drawn, typically from a vein in your arm. The sample is then processed to separate serum or plasma, which is tested for CD25 levels using an immunoassay method. This test does not require fasting.
When Might You Need This Test?
Your healthcare provider may order this test if you have symptoms of an overactive immune system, such as chronic inflammation, unexplained fevers, or signs of autoimmune diseases. It may also be used in research or clinical trials involving immune monitoring.
What Do Results Mean?
Results are not typically provided as absolute numbers in this format, but they are compared to reference ranges for your age and health status. Elevated levels may suggest immune activation, while lower levels might indicate suppressed immune function or certain genetic conditions.
Reference range
Presence or absence of CD25 antigen (IL-2 receptor alpha chain) staining reported. Positive staining indicates CD25 expression on lymphocytes in tissue. Interpretation is pathologist-dependent based on staining pattern, intensity, and percentage of positive cells.N/A
No special patient preparation required prior to surgical tissue collection. Fasting is not required. Inform the laboratory of any recent immunosuppressive therapy or immunomodulatory treatments.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
CD25 (IL-2 receptor alpha)
Frequently asked questions
Why might my doctor order this test?
What are common reference ranges for CD25?
Can I eat or drink before 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.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy