Serum and blister fluid levels of cytokines and chemokines in pemphigus and bullous pemphigoid

Bullous pemphigoid and pemphigus constitute two major autoimmune blistering diseases (AIBD) with complicated disease pathomechanisms involving a multitude of cytokines and immunological pathways. The purpose of our literature review of the cytokines and chemokines involved in these AIBDs was to allow for a meta-analysis of studies detailing differential cytokine and chemokine changes in these conditions. Elucidation of inflammatory pathways could lead to more targeted therapies, several of which specific monoclonal antibodies already exist and are used safely for other autoimmune diseases. A systematic review of the Pubmed/Medline database was performed for articles characterizing cytokines/chemokines involved in BP and pemphigus. Further, a meta-analysis was carried out using standardized methods, including assessment for heterogeneity. The results of our analysis demonstrated numerous inflammatory alterations in these AIBDs. Significant alterations included serum levels of IL-5, IL-6, IL-8, IL-17, CCL-17, and CCL-26 in patients with BP, and increased blister fluids levels of IL-5, IL-6, IL-8, CCL11, and TNF-alpha. Blister fluid levels of IL-1 alpha are decreased in BP. In pemphigus, we identified significantly increased serum levels of IL-10, IL-17, and CCL17. We have additionally summarized all studies excluded from meta-analysis to provide a comprehensive summary of cytokine/chemokine alterations in these two conditions.