Supplier: STEMCELL Technologies

Stem cell factor (SCF) is an early-acting cytokine that plays a pivotal role in the regulation of embryonic and adult hematopoiesis. SCF promotes cell survival, proliferation, differentiation, adhesion, and functional activation of cells at multiple levels of the hematopoietic hierarchy. Together with other cytokines such as thrombopoietin and Flt3/Flk-2 Ligand, SCF is commonly used to promote expansion of primitive hematopoietic stem cells and multi-potent progenitor cells in culture (Martin et al.; Kent et al.). In synergy with various growth factors, including IL-2, IL-3, IL-6, IL-7, G-CSF, and erythropoietin, SCF increases proliferation and differentiation of myeloid and erythroid progenitor cells and a subset of lymphoid progenitor cells (Broudy). SCF is also a primary growth and activation factor for mast cells and eosinophils. SCF exists in two biologically active splice forms: a soluble and a transmembrane isoform. Upon binding to its receptor (c-Kit tyrosine kinase receptor; CD117), it activates PI3K, JAK/STAT, and MAPK pathways. SCF and signaling from c-Kit have also been reported to play an important role in pigmentation, fertility, vasculogenesis, motility of the gut via c-Kit positive interstitial cells of Cajal, and in the migration of neuronal stem and progenitor cells to sites of injury in the brain.

Supplier: STEMCELL Technologies

Macrophage colony-stimulating factor (M-CSF) is a homodimeric glycoprotein growth factor that regulates proliferation and differentiation of myeloid hematopoietic progenitors to mononuclear phagocytic cell lineages, including monocytes, macrophages, and osteoclasts. M-CSF is a crucial factor for the development of tissue-resident macrophages in most tissues (Ginhoux andamp; Jung). It is required for the maturation and activation of monocytes and macrophages, and regulates inflammatory responses in conjunction with other stimuli such as IFN-γ, LPS, and IL-4 (Murray et al.). M-CSF is also required for bone resorption by osteoclasts, and is involved in the development and regulation of placenta, mammary gland, and brain. M-CSF is produced by monocytes, fibroblasts, osteoclasts, stromal cells, endothelial cells, and tumor cells (Chockalingam andamp; Ghosh). M-CSF exerts its biological effects by signaling through a receptor tyrosine kinase (CSF-1R or M-CSF-R) encoded by the c-fms proto-oncogene (Hamilton). CSF-1R shares similar structural features with other growth factor receptors, including the stem cell factor (SCF) receptor, platelet-derived growth factor receptor (PDGF-R), and Flt3/Flk-2 receptor tyrosine kinase. Stimulation of the CSF-1R upon binding to M-CSF activates MAPK, PI3K, and PLCγ signaling pathways (Chockalingam andamp; Ghosh). Human and mouse M-CSF sequences are highly conserved both at nucleotide and amino acid levels (80% homology; DeLamarter et al.). This product is animal component-free.

Supplier: STEMCELL Technologies

Flt3/Flk-2 (Fms-like tyrosine kinase 3/fetal liver kinase-2) Ligand is a hematopoietic cytokine that plays an important role as a co-stimulatory factor in the proliferation, differentiation, and survival of hematopoietic stem and progenitor cells and the development of the immune system (Hannum et al.). Flt3/Flk-2 Ligand, together with stem cell factor and thrombopoietin, is commonly used to promote expansion of primitive CD34+ hematopoietic cells in culture. In combination with myeloid cytokines such as GM-CSF, G-CSF, or M-CSF, Flt3/Flk-2 Ligand enhances the growth and numbers of clonogenic myeloid progenitor cells. In synergy with the interleukins IL-3, IL-4, IL-7, IL-11, IL-12, IL-15, and GM-CSF and TNF-α, Flt3/Flk-2 Ligand regulates the development of various lymphoid progenitor cells, including dendritic cell, B cell, T cell, and NK cell progenitors. In contrast, Flt3/Flk-2 Ligand has no significant effect on erythropoiesis or megakaryopoiesis (Drexler and Quentmeier; Wodnar-Filipowicz). Flt3/Flk-2 Ligand exists as membrane-bound and soluble isoforms. Both isoforms are biologically active and signal through the class III tyrosine kinase receptor (Flt3/Flk-2, CD135; Rosnet et al.). Flt3/Flk-2 Ligand is produced by a variety of cell types, including uncommitted and committed hematopoietic cells and stromal fibroblasts, whereas expression of the Flt3/Flk-2 receptor is restricted to CD34+ hematopoietic stem and progenitor cells. Flt3/Flk-2 receptor is also expressed on leukemic cells and outside the hematopoietic system in the brain, placenta, and testis (Drexler and Quentmeier; Hannum et al.). This product is animal component-free.