IL-4 is primarily produced by activated T cells, generated by the Th2 subset in mice. Additionally, mast cells, IL-2 stimulated murine T cell line 2.19, ConA stimulated human Th clone 2F1, murine thymoma EL-4 cells, and B cell line CH12 all have the capability to secrete IL-4.
IL-4 receptor (IL-4R) consists of 802 amino acid residues with a molecular weight of 140kDa. IL-4R is present on the surface of T cells, B cells, thymocytes, bone marrow cells, macrophages, and mast cells in mice, with a receptor number ranging from 100-2000 per cell.
IL-4 has entered phase II clinical trials as a tumor immune regulator and clinical trials for treating immunodeficiency disorders have commenced. Due to evidence both in vivo and in vitro showing IL-4's ability to inhibit the secretion of IL-1, IL-6, and TNF, while promoting IL-1ra production, the utilization of IL-4 may offer a new approach for treating septic shock.