About InVivoSIM anti-human PD-L1 (Avelumab Biosimilar) This non-therapeutic biosimilar antibody uses the same variable regions from the therapeutic antibody Avelumab making it ideal for research use. This Avelumab biosimilar reacts with human PD-L1 (programmed death ligand 1) also known as B7-H1 or CD274. PD-L1 is a 40 kDa type I transmembrane protein that belongs to the B7 family of the Ig superfamily. PD-L1 is expressed on T lymphocytes, B lymphocytes, NK cells, dendritic cells, as well as IFNγ stimulated monocytes, epithelial cells and endothelial cells. PD-L1 binds to its receptor, PD-1, found on CD4 and CD8 thymocytes as well as activated T and B lymphocytes and myeloid cells. Engagement of PD-L1 with PD-1 leads to inhibition of TCR-mediated T cell proliferation and cytokine production. PD-L1 is thought to play an important role in tumor immune evasion. Induced PD-L1 expression is common in many tumors and results in increased resistance of tumor cells to CD8 T cell mediated lysis. Avelumab blocks the interaction of PD-L1 with PD-1 and CD80. InVivoSIM anti-human PD-L1 (Avelumab Biosimilar) Specifications IsotypeHuman IgG1, λ Recommended Isotype Control(s)RecombiMAb human IgG1 isotype control, anti-respiratory syncytial virus Recommended Dilution BufferInVivoPure pH 7.0 Dilution Buffer ImmunogenFull length human PD-L1 Reported Applicationsin vitro functional assay in vitro PD-L1 blockade ELISA FormulationPBS, pH 7.0 Contains no stabilizers or preservatives Endotoxin<0.5EU/mg (<0.0005EU/μg) Determined by LAL gel clotting assay Aggregation<5% Determined by SEC Purity>95% Determined by SDS-PAGE Sterility0.2 μm filtration ProductionPurified from cell culture supernatant in an animal-free facility PurificationProtein A Molecular Weight150 kDa StorageThe antibody solution should be stored at the stock concentration at 4°C. Do not freeze. Application ReferencesInVivoSIM anti-human PD-L1 (Avelumab Biosimilar) (CLONE: Avelumab)Müller T, Tasser C, Tesar M, Fucek I, Schniegler-Mattox U, Koch J, Ellwanger K (2023). "Selection of bispecific antibodies with optimal developability using FcRn‑Ph‑HPLC as an optimized FcRn affinity chromatography method" MAbs 15(1):2245519. PubMedA challenge when developing therapeutic antibodies is the identification of candidates with favorable pharmacokinetics (PK) early in development. A key determinant of immunoglobulin (IgG) serum half‑life in vivo is the efficiency of pH-dependent binding to the neonatal Fc receptor (FcRn). Numerous studies have proposed techniques to assess FcRn binding of IgG-based therapeutics in vitro, enabling prediction of serum half-life prior to clinical assessment. FcRn high-performance liquid chromatography (HPLC) assays FcRn binding of therapeutic IgGs across a pH gradient, allowing the correlation of IgG column retention time to the half‑life of a therapeutic IgG in vivo. However, as FcRn retention time cannot be directly compared to an in vivo parameter, modifications to FcRn-HPLC are required to enable interpretation of the data within a physiological context, to provide more accurate estimations of serum half-life. This study presents an important modification to this method, FcRn-pH-HPLC, which reproducibly measures FcRn dissociation pH, allowing correlation with previously established half-lives of therapeutic antibodies. Furthermore, the influence of incorporating various antibody modifications, binding modules, and their orientations within IgGs and bispecifics on FcRn dissociation pH was evaluated using antibodies from the redirected optimized cell killing (ROCK®) platform. Target and effector antigen-binding domain sequences, their presentation format and orientation within a bispecific antibody alter FcRn retention; tested Fc domain modifications and incorporating stabilizing disulfide bonds had minimal effect. This study may inform the generation of mono-, bi- and multi-specific antibodies with tailored half-lives based on FcRn binding properties in vitro, to differentiate antibody-based therapeutic candidates with optimal developability.