CD40 & CD40 Ligand

Immunology

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Description

CD40 ligand (CD40L/CD154) is a membrane glycoprotein on activated T cells that induces B cell proliferation and immunoglobulin secretion via CD40 on the surface of B cells [1]. Defects in CD40 or CD40 ligand can reduce the class switching of immunoglobulins from IgM to IgG, IgA, IgD or IgE. There are several distinct forms of hyper IgM syndrome. It is an X-linked immunodeficiency that causes reduced or absent expression of CD40L. This disease is characterized by elevated concentrations of serum IgM and decreased amounts of all other isotypes [2]. Clinically patients present with recurrent infections, particularly with opportunistic agents such as Pneumocystis carinii.

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Indications

X-linked hyper IgM syndromes.

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Sample Type

10-20mL Heparinised (unpreserved) whole blood - (Collection vials available from Immunology). Please sent a control sample collected at the same time as the patient sample. Samples must be urgently transported to the laboratory. Requests from outside Sheffield: Please discuss transport requirements prior to requesting this test.

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Reference Range

See report for interpretation.

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Turnaround Time

Within 3 days

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Testing Frequency

Discuss with Immunology prior to requesting test.

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References

Durandy A, Peron S, Fischer A. Hyper IgM syndromes. Curr Opin Rheum. 2006. 18:369-376.
Grewal IS, Flavell RA. The role of CD40 ligand in costimulation and T-cell activation. Immunol Rev. 1996. 153:85-106. [Ref 1]
Allen RC, et al. CD40 ligand gene defects responsible for X-linked hyper-IgM syndrome. Science. 1993. 259:990-993. [Ref 2]

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Please note: the above information is subject to change and we endeavour to keep this website up to date wherever necessary.