CD40 ligand (CD40L)

Diagnostic Use

X linked hyper-IgM (XHIM) syndrome is a primary immunodeficiency caused by mutations in the tumour necrosis factor superfamily 5 gene, TNFSF5, also known as the CD40 ligand (CD40L) or CD154 gene. Patients often present with recurrent infections, and confirmation of a diagnosis of XHIM enables appropriate therapeutic interventions, including replacement immunoglobulin, antibiotics, and bone marrow transplantation.

Department

Immunology

Delphic Registration Code

LIGA

Laboratory Handling

Registration

Phone lab and send direct to immunology or after hours place into immunology bin at room temperature

Turnaround Time

1 week

Specimen Type

• Whole Blood

Specimen Requirements

Tube/Container Type:

Preferred

• Lithium Heparin - Non-gel (Green Cap)

Preferred Sample Volume (ml)

1

No of Samples Required

2

Paediatric Specimen Requirements

Tube/Container Type:

Preferred

• Lithium Heparin - Non-gel (Green Cap)

Preferred Sample Volume (ml)

0.5

Additional Specimen Information

Laboratory MUST be contacted before sample is taken (03) 364 0413. 1 week's notice is required.

Patient sample: 1 mL Heparin from pt + healthy unrelated ctrl

Paediatric sample: 0.5 mL Heparin from pt + healthy unrelated ctrl

Aliquot Instructions

Sample Type

• Whole Blood

Minimum Volume (ml)

1

Transport to Lab

Ambient (8 - 24 degrees Celsius)

Additional Referral/Aliquot Information

Ambient temperature within 24h.

Reference Intervals

– Normal expression
– Weak expression
– Absent expression

Test Method

Whole blood is incubated overnight with PMA (phorbol 12-myristate 13-acetate) and PHA (phytohaemagglutinin-L) to stimulate lymphocytes, which are then stained with the appropriate antibodies and the red blood cells lysed. Flow cytometry is used to determine whether CD40L is expressed on the activated lymphocytes.

Non-Funded Test Cost

$419.71 (Exclusive of GST)

Billing Code

8782

Additional Costing Information

Lymphocytes are also checked for CD25 levels to ensure adequate stimulation following incubation with PMA and PHA.

Contact Information

Enquiry Form