IFN-γ/IL-6 and related cytokines in chronic spontaneous urticaria: evaluation of their pathogenetic role and changes during omalizumab therapy.

BACKGROUND

Recent studies highlight that high levels of cytokines may precede the onset of many systemic autoimmune disorders and may also be related to chronic spontaneous urticaria (CSU) activity.

METHODS

Eight patients with CSU candidate to omalizumab therapy were enrolled. Four healthy controls were included with the purpose of comparing baseline cytokine levels. We evaluated serum levels of IFN-γ, IL-2, 4, 6, 8, and 10, TNF-α, and GM-CSF. For the patient group, venous blood samples were drawn at T0, T1 (1 week after first drug administration), T2 (after 3 months), T3 (after 6 months), and in case of relapse. Cytokine levels were measured using the human cytokines 8-plex kit. Disease activity and effect of therapy were calculated by means of Urticaria Activity Score 7.

RESULTS

Higher levels of IL-6 and IFN-γ were found in patients with CSU compared to those observed in the control group. Moreover, a common trend between these cytokines and the clinical history of disease could be hypothesized, with a decrease in levels of IFN-γ and IL-6 following remission of CSU with omalizumab treatment. Levels of other tested cytokines were similar between patients and healthy subjects.

CONCLUSION

IFN-γ and IL-6 are proinflammatory cytokines that are strongly related to autoimmunity. Despite being limited by the small sample size, our data offer new insight into a better understanding of the pathogenesis of CSU and support the need for further investigations.