IL-3 (Interleukin-3) is a cytokine that regulates haemopoiesis, the formation of blood cells in the body. IL-3, also called multi-CSF (multi-lineage colony stimulating factor), is produced by T cells and mast cells, after activation with mitogens or antigens. The molecular weight of IL-3, a protein of 140 amino acids, ranges from 14 to 36 kDa. It stimulates eosinophils and B cell differentiation while it inhibits LAK (Lymphokine-Activated Killer) cell activity. IL-3 shares several biological activities with GM-CSF. IL-3 is capable of inducing the growth and differentiation of multi-potential haematopoetic stem cells, neutrophils, eosinophils, megakaryocytes, macrophages, lymphoid and erythroid cells (Ref.1). IL-3R (IL-3 receptor) is composed of two polypeptide chains, an Alpha subunit of 60-70kDa and a Beta subunit of 130-140kDa. Both subunits contain the extracellular conserved motifs found [...]