1. Assessment of CD40L expression and function for diagnosis of X-linked hyper-IgM syndrome (XL-HIGM).
Assessment of CD40L expression and function for diagnosis of X-linked hyper-IgM syndrome (XL-HIGM). The top left panel (panel 1) shows expression of CD40L (CD154) on activated CD4+ T cells after stimulation with PMA. A control for T cell activation, CD69, is included in the assay (not shown). Functional activity of the ligand is measured by binding to a soluble form of the receptor—CD40muIg (panel 2). The bottom panels show flow cytometric data for a male patient with XL-HIGM with lack of expression of CD40L on activation of CD4+ T cells (panel 3) and therefore, no binding to the soluble receptor (panel 4). The grey peak represents the unstimulated sample. The purple peak represents the specific antibody.
Roshini S. Abraham, and Geraldine Aubert Clin. Vaccine Immunol. 2016; doi: /CVI