Product Description
This Rat PD-L1 overexpression lysate was created in HEK293 Cells and intented for use as a Western blot (WB) positive control. Purification of PD-L1 protein (Cat: 80450-R08H) from the overexpression lysate was verified.
Expression Host
HEK293 Cells
Sequence Information
A DNA sequence encoding the rat CD274 (NP_001178883.1)(Met1-Thr238) was expressed with a polyhistidine tag at the C-terminus.
Molecule Mass
The recombinant rat CD274 comprises 232 amino acids and predicts a molecular mass of 26.5 kDa. The apparent molecular mass of the recombinant protein is approximately 50.7 kDa in SDS-PAGE under reducing conditions.
Preparation Method
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.
Lysis Buffer
Modified RIPA Lysis Buffer: 50 mM Tris-HCl pH 7.4, 150 mM NaCl, 1mM EDTA, 1% Triton X-100, 0.1% SDS, 1% Sodium deoxycholate, 1mM PMSF.
Recommend Usage
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.
Sample Buffer
1 X Sample Buffer (1 X modified RIPA buffer+1 X SDS loading buffer).
Stability & Storage
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.
Application
Western Blot (WB)
Optimal dilutions/concentrations should be determined by the end user.
References
Iwai Y, et al. (2002) Involvement of PD-L1 on tumor cells in the escape from host immune system and tumor immunotherapy by PD-L1 blockade. Proc Natl Acad Sci U S A. 99(19): 12293-7. Ghebeh H, et al. (2006) The B7-H1 (PD-L1) T lymphocyte-inhibitory molecule is expressed in breast cancer patients with infiltrating ductal carcinoma: correlation with important high-risk prognostic factors. Neoplasia. 8(3): 190-8. Salih HR, et al. (2006) The role of leukemia-derived B7-H1 (PD-L1) in tumor-T-cell interactions in humans. Exp Hematol. 34(7): 888-94. Wilcox RA, et al. (2009) B7-H1 (PD-L1, CD274) suppresses host immunity in T-cell lymphoproliferative disorders. Blood. 114(10): 2149-58. Ruggiero A, et al. (2009) Crystal structure of PD-L1, a ribosome inactivating protein from Phytolacca dioica L. leaves with the property to induce DNA cleavage. Biopolymers. 91(12): 1135-42.