兔單克隆抗體[28-8] to PD-L1RabbitMonoclonal Rabbit IgG Clone #015UnconjugatedThis antibody was obtained from a rabbit immunized with purified, recombinant Human PD-L1 / B7-H1 / CD274 (rh PD-L1 / B7-H1 / CD274; Catalog#10084-H08H; NP_054862.1; Met 1-Thr 239).適用于: IHC-P, WB, Flow Cyt, ICC/IF

Immunohistochemistry (Formalin/PFA-fixed paraffin-embedded sections) - Anti-PD-L1 antibody [28-8] (ab205921)

IHC image of ab205921 staining PD-L1 in human tonsil formalin fixed paraffin embedded tissue sections*, performed on a Leica BOND RX (Polymer Refine kit). The section was pre-treated using heat mediated antigen retrieval with EDTA buffer (pH9, epitope retrieval solution 2) for 30 mins at 98°C. The section was then incubated with ab205921, 5μg/ml working concentration, for 60 mins at room temperature and detected using an HRP conjugated compact polymer system for 8 minutes at room temperature. DAB was used as the chromogen for 10 minutes at room temperature. The section was then counterstained with hematoxylin, blued, dehydrated, cleared and mounted with DPX.
For other IHC staining systems (automated and non-automated) customers should optimize variable parameters such as antigen retrieval conditions, primary antibody concentration and antibody incubation times.
*Tissue obtained from the Human Research Tissue Bank, supported by the NIHR Cambridge Biomedical Research Centre

Programmed death-1 ligand-1 (PD-L1, CD274, B7-H1) has been identified as the ligand for the immunoinhibitory receptor programmed death-1(PD1/PDCD1) and has been demonstrated to play a role in the regulation of immune responses and peripheral tolerance. PD-L1/B7-H1 is a member of the growing B7 family of immune molecules and this protein contains one V-like and one C-like Ig domain within the extracellular domain, and together with PD-L2, are two ligands for PD1 which belongs to the CD28/CTLA4 family expressed on activated lymphoid cells. By binding to PD1 on activated T-cells and B-cells, PD-L1 may inhibit ongoing T-cell responses by inducing apoptosis and arresting cell-cycle progression. Accordingly, it leads to growth of immunogenic tumor growth by increasing apoptosis of antigen specific T cells and may contribute to immune evasion by cancers. PD-L1 thus is regarded as promising therapeutic target for human autoimmune disease and malignant cancers.雙抗體夾心法測定標本中PD-L1水平。用純化的PD-L1抗體包被微孔板，制成固相抗體，往包被單抗的微孔中依次加入PD-L1，再與HRP標記的PD-L1抗體結(jié)合，形成抗體-抗原-酶標抗體復合物，經(jīng)過徹底洗滌后加底物TMB顯色。TMB在HRP酶的催化下轉(zhuǎn)化成藍色，并在酸的作用下轉(zhuǎn)化成最終的黃色。顏色的深淺和樣品中的PD-L1呈正相關(guān)。用酶標儀在450nm波長下測定吸光度（OD值），通過標準曲線計算樣品中PD-L1濃度。
ANTI-PD-L1抗體是一類可以特異性結(jié)合PD-L1的多克隆抗體，主要用于檢測PD-L1的Western Blot、IHC-P、IF、ELISA、Co-IP等多種免疫學實驗。

PD-1的全稱是程序性死亡受體-1，屬于CD28超家族成員，是由268個氨基酸組成的I型跨膜蛋白。它是在1992年由日本京都大學的Tasuku Honjo教授發(fā)現(xiàn)的，可在T細胞、B細胞等免疫細胞表面表達。不過在T細胞未活化時，幾乎不表達PD-1，僅在T細胞活化之后，PD-1才在T細胞表面表達。
PD-L1(programmed death ligand 1)全稱程序性死亡受體配體1，是PD-1（programmed cell death 1,程序性死亡受體1）的配體。PD-L1屬于細胞膜上的一個跨膜蛋白，表達在T細胞、B細胞等免疫細胞以及腫瘤細胞上，研究表明當腫瘤細胞膜上的PD-L1與T細胞等免疫細胞上的PD-1結(jié)合后，腫瘤細胞發(fā)出抑制性信號，進而T細胞不能識別腫瘤細胞和對腫瘤細胞產(chǎn)生殺傷作用，機體的免疫功能受到抑制。