Complement C4a
Also known as: Complement C4a des-Arginine
Use
Activation of the complement system plays an important role in our natural ability to ward off infection and in the pathogenesis of infection and inflammation.1-6 Anaphylatoxins produced as the result of complement activation play a role in a number of infectious and inflammatory conditions including sepsis, ischemia-reperfusion injury, immune complex diseases, and hypersensitivity diseases like asthma.1 Anaphylatoxins are also thought to be important in the pathogenesis of allergy, autoimmunity, neurodegenerative diseases, and cancer.2,3
Special Instructions
Futhan preservative must be added to samples immediately after collection, and collection kits containing this preservative are available as LabCorp N° 78946. Blood must be drawn directly into tubes containing EDTA at a final concentration of at least 10 mM, with additional Futhan to reduce in vitro complement activation. To avoid delays, separate frozen specimens should be submitted for each test requested.
Limitations
Results are intended for research purposes only by the assay's manufacturer, and performance characteristics have not been established. The test results should not be relied upon as a diagnostic procedure without further confirmation from a medically established diagnostic product. Elevation in C4a levels is not indicative of any specific disease and can occur in any inflammatory condition. Improper collection or storage of samples can result in erroneously elevated results due to in vitro activation.
Methodology
Immunoassay (RIA)
Biomarkers
LOINC Codes
- 4501-3
- 4501-3
Result Turnaround Time
4-7 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Lavender-top (EDTA) tube
Collection Instructions
Collect EDTA whole blood sample into a chilled lavender-top tube. Immediately add Futhan preservative as directed in the Futhan collection kit. Recap lavender tube and invert several times to mix well. Centrifuge the whole blood specimen to separate the plasma. Transfer the plasma into the plastic screw-cap tube that is included in the collection kit. The specimen must be submitted in this transfer tube labeled 'Futhan Added.' Freeze immediately and maintain frozen until tested.
Patient Preparation
No radioactive isotopes administered within 48 hours prior to venipuncture.
Storage Instructions
Freeze
Causes for Rejection
No Futhan label added; non-Futhan label applied to tube; non-EDTA plasma; gross lipemia; gross hemolysis; turbid samples received
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 6 hours |
| Refrigerated | 5 days |
| Frozen | 14 days |
Other tests from different labs that may be relevant