Bovine IL-4 ELISA Kit

Interleukin-4, abbreviated IL-4, is a cytokine that is expressed in a variety of tissues including
lymphocytes and leukocytes, is a key regulator in humoral and adaptive immunity and has many
biological roles, including the stimulation of activated B-cell and T-cell proliferation, and the
differentiation of CD4+ T-cells into Th2 cells. IL-4 induces differentiation of naive helper T cells
(Th0cells) to Th2 cells. Upon activation by IL-4, Th2 cells su b sequently produce additional IL-4. The 

cell that initially produces IL-4, thus inducing Th0 differentiation, has not been identified, but
recent studies suggest that basophils may be the effector cell. It is closely related and has functions
similar to Interleukin 13.Like IL-13, Interleukin 4 (IL-4) is critical for responses to parasitic
helminthes. IL-4 up-regulates MHC class II production and decreases the production of Th1 cells,

macrophages, IFN-gamma, and dendritic cell IL-12. Tissue macrophages play an important role in
chronic inflammation and wound repair. The presence of IL-4 in extravascular tissues promotes
alternative activation of macrophages into M2 cells and inhibits classical activation of macrophages
into M1 cells. An increase in repair macrophages (M2) is coupled with secretion of IL-10 and TGF-β
that result in a diminution of pathological inflammation. This cytokine was co-discovered by
Maureen Howard and William Paul and by Dr. Ellen Vitetta and her research group in 1982. The
nucleotide sequence for human IL-4 was isolated four years later confirming its similarity to a mouse
protein called B-cell stimulatory factor-1 (BCSF-1).