Cytokine Release from Stimulated PBMC after-HSCT: Results of a Post-Transplant Zinc Oral Supplementation Trial (ZENITH).

Introduction: the immune system may take months to recover after hematopoietic stem cell transplantation (HSCT). One important factor involved in the immune reconstitution is the recovery of the thymic production of a new T-cell repertoire, the other is the homeostatic peripheral expansion of mature lymhpocytes (HPE). It is known that HPE affect in a negative way the killing functions of the mature lymphocytes and their ability in secreting cytokines. On the other hand, the production of recent thymic emigrants (RTEs) by the thymus confers a broader spectrum against pathogens, but it needs a longer time. Zinc is fundamental for immune cells: several studies demonstrated that Zinc causes regrowth of thymic epithelial cells (TECs) in adults, improving the production of RTEs. Many studies showed the ability of Zinc to improve the in vitro cytokine release from immune cells, and others demonstrated its anti-apoptotic role on mature lymphocytes. As described elsewhere, we performed a clinical trial with the aim of investigating a potential therapeutic role of Zinc after HSCT (ZENITH trial). Here we illustrate the results of the cytokine release assays performed on the peripheral blood mononucleated cells (PBMC) isolated from the patients participating to the ZENITH trial.