Recombinant Mouse IL-4 (carrier-free)

IL-4 is a member of the short four-helix bundle family of cytokines. IL-4 is produced by Th2 cells in response to antigen receptor engagement. Dendritic cells can prime naïve CD4+ T cell; nevertheless, it has been described that DC-mediated priming is insufficient for the development of Th2 cell-dependent immunity. Basophils have been identified as a source or IL-4 in the initial naïve CD4+ T cell priming. These cells coexpress MHC class II and IL-4 message following helminth infection. Therefore, murine basophils could present antigens to naïve T cells, thus promoting Th2 cell differentiation during allergic and anti-parasitic immune responses. In addition, it was previously known that upon cross-linkage of the high affinity receptor for immunoglobulin E, IL-4 is produced by NK cells, mast cells, and basophils. Cells of hematopoietic stem cell origin express the type I receptor for IL-4 (IL-4Ra,gc), and cells of non-hematopoietic stem cell origin express type II receptor (IL-4Ra, IL-13Ra1). Type I receptor complexes are active in regulating Th2 development. In contrast, the type II receptor complex is active in regulating cells that mediate airway hypersensitivity and mucus secretion.