CD62L shedding assay

Also known as: CD62L; TLRs; IRAK4; UN93b

All requests for a CD62L shedding assay must be discussed with the laboratory's medical staff and/or Senior Clinical Scientist

This test detects functional defects in Interleukin-1 receptor associated kinases (IRAK)-4 and MyD88 in the Toll-like Receptor (TLR) pathways. IRAK-4 or MyD88 deficiency impairs neutrophil activation through ablation of TLR mediated microbial sensing, therefore patients are susceptible to recurrent serious bacterial and fungal infections.

This also detects patients with a defect in a protein in another TLR pathway, UNC93b. Patients with a deficiency in this protein suffer from Herpes simplex virus (HSV) encephalitis.

Patients with defects in all these proteins have abnormal shedding of CD62L from their neutrophils with stimulation with TLR ligands.

Patients suspected of a TLR problems fall into two groups:

1. Children under the age of 5 with recurrent bacterial infections and signs of low neutrophil/CRP levels.
2. Adults with a long history of recurrent infections characterised by low CRP – due to the recent application of test it is hypothesised that pre-existing undiagnosed IRAK-4 patients exist

Specimen requirements

A minimum of 1ml EDTA blood are required and must be received by the immunology laboratory within 6 hours of venepuncture and before 3pm. Samples must NOT have been refrigerated or centrifuged.

A healthy control sample is required for the assay. If the sample is being transported from another hospital please include a control sample (from an unrelated, healthy adult) as a transport control.

Cost

Price on application

Laboratory turnaround time

3 working days

Laboratory method

FACSCanto

Reference range/units

N/A

Associated tests

N/A

Sample stability

6 hours post venepuncture

Shipping and storage

• Samples must be received by the immunology laboratory within 8 hours of venepuncture and before 3pm.
• Samples must NOT have been refrigerated or centrifuged.
• A healthy control sample is required for the assay. If the sample is being transported from another hospital please include a control sample (from an unrelated, healthy adult) as a transport control.
• Local venepuncture may be arranged (please contact a senior member of staff).

UKAS Accreditation status

This test is currently not accredited due to changes in method.

Further information and contact details

For further information, email immunology.office@nhs.net