LIF is a pleiotrophic factor produced by multiple cell types, including T cells, myelomonocytic lineages, fibroblasts, liver, heart and melanoma. LIF promotes long-term maintenance of embryonic stem cells by suppressing spontaneous differentiation. Other activities include the stimulation of acute phase protein synthesis by hepatocytes, stimulation of differentiation of cholinergic nerves, and suppression of adipogenesis by inhibiting the lipoprotein lipase in adipocytes. While human LIF is active on mouse cells and is widely used in the maintenance of murine ESC to prevent spontaneous differentiation, mouse LIF is not active on human cells due to its inability to bind to the human LIF receptor. Recombinant Murine LIF is a 19.9 kDa protein containing 180 amino acids residues, including three disulfide bonds.
Greater than 98% by SDS-PAGE gel and HPLC analyses.
生物活性:
PeproTech's Murine LIF is fully biologically active when compared to standards. The ED50 as determined by the M1 cell differentiation assay is ≤ 0.05 ng/ml, corresponding to a specific activity of ≥ 2 x 107 units/mg.
交叉反应:
Mouse
重组人与小鼠LIF的主要应用: 培养小鼠胚胎干细胞必需的细胞因子优势:1. 生物活性高:≥2 x 107 units/mg (通过抑制M1细胞分化检测);2. 纯度较高:>98%;3. 规格齐全:有大包装提供,可定制分装;4. 内毒素极低:尤其是Animal Free的LIF,<0.1 ng/μg of protein (<1EU/μg);5. 产品性状:冻干粉 (稳定性好,保质期长)。背景介绍LIF的英文全称为Leukemia Inhibitory Factor,中文译为白血病抑制因子,是一种具有多种功能的细胞因子,LIF是IL-6家族成员,与IL-6R共用信号转导亚单位gp130。LIF最重要的应用是通过抑制自发分化来维持小鼠胚胎干细胞的未分化状态。mES(小鼠胚胎干)细胞的维持培养液 (有饲养层培养)以配制500ml mES培养液为例,按下表配制,配制后,4℃可储存2周。