KL-1 Peptide corresponds to aa 185-196 of Kit Ligand (KITLG, KL) also known as Stem Cell Factor (SCF). A soluble form (sKITLG) is produced by proteolytic processing of transmembrane KITLG at aa190. KL-1 peptide is used as a substrate for proteases such as furin. SCF stimulates the proliferation of mast cells, augments the proliferation of both myeloid and lymphoid hematopoietic progenitors in bone marrow culture, and mediates cell-cell adhesion. SCF acts synergistically with other cytokines such as interleukins.