C2

Immunology

Description

C2 is a component of the classical Complement activation pathway. It is cleaved by activated C1s into two fragments, C2a and C2b. C2a combines with C4b to form C3 and C5 convertase. Genetic deficiency of C2 is the most common complement deficiency and is nearly always caused by a 28bp deletion in the C2 gene [2]. C2 deficiency is associated with SLE, glomerulonephritis, and vasculitis [1]. Approximately 25% of C2 homozygote deficient patients are suspceptible to severe infections. Reductions in C2 can also arise due to consumption following classical complement pathway activation [3].

Indications

Immune complex disease / complement consumption / complement deficiency.

Sample Type

2mL Serum (Gel 5mL Yellow tube). Transport fresh or freeze if sample is not sent on the day of venesection. Requests from outside Sheffield: Transport at ambient temperature via Royal Mail or Courier (frozen samples can thaw in transit).

Reference Range

10-30 mg/L.Reference range established in house and PRU collaboration.

Turnaround Time

Within 3 weeks

Testing Frequency

1 - 4 Weeks

External Notes

Discuss with Clinical Scientist/ Medical Staff.

References

PRU Handbook of Clinical Immunochemistry. 9th Ed. 2007. [Ref 1]Sjoholm AG, et al. Complement deficiency and disease: an update. Mol Immunology. 2006. 43(1-2):78-85. [Ref 2]Alper CA, et al. Immunoglobulin deficiencies and susceptibility to infection among homozygotes and heterozygotes for C2 deficiency. J Clin Imm. 2003. 23:297-305. [Ref 2]

Your contact for this test

Clare Del-Duca BSc (Hons) Biomedical Science, MSc Pathological Science

Laboratory Manager - Immunology and Protein Reference Unit

C2