REAfinity™ Recombinant Antibodies: Background-Free Analysis Of Mouse TILs

Syngeneic mouse tumor models are widely regarded as the gold standard for analyzing the effects of immunotherapy due to their fully competent immune repertoire. These models are essential for studying tumor-infiltrating leukocytes (TILs) and their phenotypes, which are crucial for understanding the immune response within the tumor microenvironment. However, the variability in the amount and composition of TILs can complicate the flow cytometric analysis of individual subpopulations, as the presence of TILs is often very low and highly variable. Adding to the complexity, traditional hybridoma-derived antibody clones used in flow cytometric evaluations of TILs tend to bind nonspecifically to immune cells, such as myeloid cells, through naturally expressed Fcγ receptors (FcγR) or induced expression of FcγRs on T cells within the tumor microenvironment.

To mitigate FcγR-mediated background binding, researchers use blocking reagents, including commercially available immunoglobulins. However, this introduces additional challenges, as there is no established consensus on the optimal titer and type of blocking reagent for complex tissues like tumors.

Discover how the use of blocking reagents increases staining time and complicates the scaling up or automation of multisample analyses, which makes the process more labor-intensive and less efficient.