This Human CD55/DAF overexpression lysate was created in HEK293 Cells and intented for use as a Western blot (WB) positive control. Purification of CD55/DAF protein (Cat: 10101-H08H) from the overexpression lysate was verified.
A DNA sequence encoding the human CD55 precursor (NP_000565.1) (Met 1-Ser 353) was expressed, with a C-terminal polyhistidine tag.
The secreted recombinant human CD55 consists of 330 amino acids and has a predicted molecular mass of 36.5 kDa. In SDS-PAGE under reducing conditions, the apparent molecular mass of rhCD55 is approximately 55-60 kDa due to glycosylation.
Human CD55/DAF HEK293 Overexpression Lysate: 使用指南
Cell lysate was prepared by homogenization of the over-expressed cells in ice-cold modified RIPA Lysis Buffer with cocktail of protease inhibitors (Sigma). Cell debris was removed by centrifugation. Protein concentration was determined by Bradford assay (Bio-Rad protein assay, Microplate Standard assay). The cell lysate was boiled for 5 min in 1 x SDS loading buffer (50 mM Tris-HCl pH 6.8, 12.5% glycerol, 1% sodium dodecylsulfate, 0.01% bromophenol blue) containing 5% b-mercaptoethanol, and lyophilized.
1. Centrifuge the tube for a few seconds and ensure the pellet at the bottom of the tube.
2. Re-dissolve the pellet using 200μL pure water and boil for 2-5 min.
1 X Sample Buffer (1 X modified RIPA buffer+1 X SDS loading buffer).
稳定性 & 储存条件
Store at 4℃ for up to twelve months from date of receipt. After re-dissolution, aliquot and store at -80℃ for up to twelve months. Avoid repeated freeze-thaw cycles.
Western Blot (WB) Optimal dilutions/concentrations should be determined by the end user.
Human CD55/DAF HEK293 Overexpression Lysate: 别称
Human CR Overexpression Lysate; Human CROM Overexpression Lysate; Human DAF Overexpression Lysate; Human TC Overexpression Lysate
CD55, also well known as decay-accelerating factor (DAF), is a member of the RCA (regulators of complement activation) family characterized by four to 3 SCRs (short consensus repeats) in their plasma-exposed regions. It is a major regulator of the alternative and classical pathways of complement activation and is expressed on all serum-exposed cells. CD55 is physiologically acting as an inhibitor of the complement system, but is also broadly expressed in malignant tumours. DAF seems to exert different functions beyond its immunological role such as promotion of tumorigenesis, decrease of complement mediated tumor cell lysis, autocrine loops for cell rescue and evasion of apoptosis, neoangiogenesis, invasiveness, cell motility. It is commonly hijacked by invading pathogens, including many enteroviruses and uropathogenic Escherichia coli, to promote cellular attachment prior to infection. This 7-75 kDa glycoprotein CD55 containing four SCR modules is involved in the regulation of the complement cascade. It inhibits complement activation by suppressing the function of C3/C5 convertases, thereby limiting local generation or deposition of C3a/C5a and membrane attack complex (MAC or C5b-9) production. DAF has been identified as a ligand for an activation-associated, seven-transmembrane lymphocyte receptor, CD97, which is a receptor mediating attachment and infection of several viruses and bacteria. In addition, it has been shown that DAF regulates the interplay between complement and T cell immunity in vivo, and thus may be implicated in immune and tumor biology.
CD55 molecule, decay accelerating factor for complement (Cromer blood group)
Complement Activation Pathways
Lea S. (2002) Interactions of CD55 with non-complement ligands. Biochem Soc Trans. 30(Pt 6): 1014-9.
Mikesch JH, et al. (2006) The expression and action of decay-accelerating factor (CD55) in human malignancies and cancer therapy. Cell Oncol. 28(5-6): 223-32.
Wang Y, et al. (2010) Decay accelerating factor (CD55) protects neuronal cells from chemical hypoxia-induced injury. J Neuroinflammation. 7:24.