C-C motif chemokine receptor 9 (CCR9) is a G protein-coupled receptor, which is highly expressed in T-lymphocytes and different cancer cells. CCR9 aggravates immune diseases and cancer progression and is considered a biomarker and a therapeutic target of diseases. The development of specific monoclonal antibody (mAbs) for human CCR9 (hCCR9) is required to diagnose and treat immune diseases and cancers. Previously, we established the cell-based immunization and screening (CBIS) method, which does not need purified target proteins. Anti-hCCR9 mAb (clone C9Mab-1; mouse IgG1, kappa) was also developed using the CBIS method. C9Mab-1 is usable for flow cytometry against exogenously and endogenously expressing hCCR9. This study showed that C9Mab-1 and its recombinant antibody (recC9Mab-1) specifically detected exogenous hCCR9 stably overexpressed in Chinese hamster ovary (CHO)-K1 cells and endogenous hCCR9 expressed in a human T-lymphoblastic leukemia cell line MOLT-4 cells through immunocytochemistry. This study provides a new application of C9Mab-1 and recC9Mab-1 in immunocytochemistry.
Keywords: C9Mab-1; human CCR9; immunocytochemistry; monoclonal antibody.