There is an increasing interest towards immunotherapy in the field of oncology, as a result of excellent responses to treatments tested so far. Pharmaceutical companies have many novel immuno-oncological drugs in their pipelines.
Many of the immuno-oncological drug candidates under development are monoclonal antibodies that are specific for one immune checkpoint. The underlying mechanism of these novel immunotherapies is based on the specific antibody that blocks the interaction between a tumor antigen and its ligand, which stimulates and enhances the patient’s immune system to recognize and kill tumor cells.
Signaling and interactions between cancerous cells and the immune system is a complex process with many important players, thus offering multiple targets against which to develop and optimize novel and individual immunotherapies. Clinical work towards individualized and better patient care has started and is showing good results.
BioSiteHisto – methods & results
We at BioSiteHisto are at the front line in developing preclinical and clinical immunohistochemical (IHC) assays for drug candidates. Our sophisticated and tailored methods offer reliable results in well-controlled conditions. Our GLP compliance test facility with fully open and flexible staining platforms offers a high quality standard, especially in preclinical histopathological IHC-studies.
BioSiteHisto’s massive repertoire of optimized antibodies for the study of human and mouse cells allow us to plan and execute the best possible studies in the field of immuno-oncology. For example, we have human-specific and mouse-specific T-cell antibodies for CAR-T -studies. We also have excellent markers for tumor infiltrating lymphocytes, whose detection crucially relies upon correct and controlled methods. In addition, our markers for immune checkpoint pathways (e.g., PD-L1 and PD1, TIM3 etc.) or markers for T- and B-cell activation offer a great potential for multiplexing IHC -assays with chromogenic, fluorogenic, or a combination of these detection methods.
Figure 1. PD-L1 stained tonsil (A) and non-small cell lung carcinoma (NSCLC) (B-D). Tissue sections have been stained with PD-L1 (ZR3) antibody and 1:150 dilution. Tonsil is a good control for PD-L1 staining and epithelial crypt cells are strongly stained. Macrophages of germinal center must have a weak to moderate membranous staining reaction for an optimal staining result. Note: different expression patterns of NSCLC sections (B-D). Case B is PD-L1 negative and tumor proportion score (TPS) in case C is 1-49 %. Note alveolar macrophages and weak heterogeneous staining of pulmonary carcinoma. TPS is >50 % in case D and the expression of the PD-L1 is high.
Figure 2. PD-L1 stained cell pellet sections (A-D). Note different PD-L1 expression levels of the cells. Together with the tonsil, cell pellets are good control material for PD-L1 immunohistochemical assays. FFPE cell pellet sections have been stained with PD-L1 (ZR3) antibody and 1:150 dilution.