Interleukin 5 (IL-5) is a hematopoietic growth factor that is expressed in type 2 T helper (Th2) cells, mast cells, and eosinophils. IL-5 acts through the IL-5 receptor (IL-5R), stimulates B cell growth, and mediates eosinophil activation. Human and mouse IL-5 show cross-reactivity.
Bioactivity Assay:TF-1 cell proliferation; ED50 =0.25 ng/mL; Bioactivity =4.0 x 10^6 units/mg