Tumor necrosis factor-alpha (TNF-a) is a key inflammatory and apoptotic mediator in urticaria. However, its role is still unclear in the apoptosis-inducing pathways in chronic spontaneous urticaria.
A group of people with chronic spontaneous urticaria and healthy people had their circulating concentrations of TNF-a, soluble TNF-a receptor types 1 and 2 and soluble Fas and Fas Ligand measured using enzyme-linked immunosorbent assay.
TNF-a and soluble TNF-a receptor types 1 and 2 concentrations were significantly higher in people with moderate-to-severe chronic spontaneous urticaria than healthy people. No significant differences were found between people with mild urticaria and healthy people. There were no differences observed in Fas and Fas Ligand concentrations in all participants.
In conclusion, chronic spontaneous urticaria is associated with the activation of the TNF-a/receptors signalling pathway marked by increased circulating concentrations of TNF-a and soluble TNF-a receptor types 1 and 2. In contrast, the circulating soluble Fas/Fas Ligand system is not up-regulated in chronic urticaria and does not seem to be an useful marker for the disease.