Advanced Diagnostic Laboratories

C3a Level By RIA

Test Code

C3AR

Description

The complement system is part of our innate immune response. It is vital to our defense against invasive microorganisms. Complement activation can occur through the classical, lectin and alternative pathway, which then converge to a common terminal pathway. Activation of the complement pathway(s) results in the generation of biologically active peptides, also known as complement split products, and referred to as anaphylatoxins (C4a, C3a, C5a) which protect us from invasive microorganisms by enhancing inflammation, facilitating the clearance of immune complexes and apoptotic cells, enhancing cellular and antibody immune responses and altering vascular permeability, as well as smooth muscle contractility.

The anaphylatoxin C3a can be elevated above normal levels in many conditions associated with inflammation, including infection, asthma, sepsis, and renal diseases (IgA nephropathy, C3 glomerulonephritis) as well as immune complex diseases such as cold agglutinin-mediated autoimmune hemolytic anemia.

Collect

Plasma from a lavender top (K2-EDTA) tube is the only acceptable sample type. Mix sample thoroughly. Keep tubes cold on wet ice or with a cold pack after collection.

Patient Prep

Within 30 minutes of venipuncture, centrifuge the collection tube at 1600(±200) x g (rcf) at 4°C (± 2°C) for 15 (± 1) minutes. Transfer the cell-free plasma to a clean tube and immediately store samples at -20°C, or freeze at -60°C or below in an ultra-low freezer.

Preferred volume: 1 mL

Ambient temperature for centrifugation is acceptable provided that the time between collection and storage is minimized (approximately 30 minutes).

Pediatric Collection

Minimum volume: 0.5 mL plasma, frozen.

Unacceptable Conditions

Thawed specimen or specimens stored at room temperature prior to shipment.

Storage Transport Temp

Send frozen plasma Priority Overnight via FedEx and in a well-insulated container on dry ice.

Stability

-20°C - up to 2 weeks

-60°C or below in an ultra-low freezer - up to 2 years

Notes

Additional testing time may be needed for less than perfect samples or confirmatory/reflex testing.

Performed

Monday - Friday

Methodology

Radioimmunoassay (RIA)

Turnaround Time

21 Business days

Department

Complement Lab

Synonyms

C3 (C3a Level), C3a anaphylatoxin, C3 anaphylatoxin (C3a Level), Radio Immuno Assay (C3a Level), Complement (C3a Level), C3ades Arg Level (C3a Level), C3a des Arg Level, C3AL

Study Offerings

Not offered

Related Tests

C4AR, C3, C5AR