Cytokines: Monitors of disease severity for the clinic

Background: Cytokines communicate between the cells of the immune system and its targets to maintain homeostasis after injury or pathogenic events. They are involved in almost any pathological situation imaginable. Objective: To verify the importance of cytokines as biomarkers in current preclinical (aetiopathogenic, development of new therapies) and clinical studies (diagnosis, disease severity, prognosis and response to therapy). Method/results: A Medline search with the query 'cytokine' AND 'biomarker' AND a variable for a variety of biomedical fields, followed by deeper-level searches, demonstrated the immense popularity of cytokines as biomarkers in almost any biomedical field. Conclusion: As cytokines are not disease-specific they do not serve as single diagnostic biomarkers. The strength of the cytokines resides in monitoring disease severity, prognosis and response to treatment.