Functional characteristics of PMJ2-R macrophages

Objective. To evaluate the ability of PMJ2-R cells for classical and alternative activation and to assess the effect of oxidized dextran on the functional status of polarized cells of this line. OD is a promising lysosomotropic agent used for targeted drug delivery to phagocytic cells. Materials and methods. We analyzed ability of immortalized murine peritoneal macrophages PMJ2R (ATCC CRL2458) to classical and alternative polarization, including that upon exposure to OD. We used real-time polymerase chain reaction to assess gene expression of competing arginine pathways. The capacity of phagocytes to engulf zymosan granules was evaluated using fluorescence microscopy. Results. We observed metabolic changes in PMJ2-R cells following their classical and alternative activation; these changes were typical of M1 and M2 macrophages, respectively. M1 macrophages demonstrated most active phagocytosis, while the activity of phagocytosis in M2 macrophages increased dose-dependently upon AD exposure. OD upregulates production of proinflammatory cytokine TNF-α in intact PMJ2-R cells and M1 macrophages. Conclusion. PMJ2-R cells have the capacity to phagocytose particles, can be polarized via the classical and alternative pathway, can modulate their functional activity in response to OD (a macrophagotropic substance), and exhibit the main phenotypic properties typical of peritoneal macrophages from C57Bl/6J mice. Therefore, cells of this line can be used as model cells in the investigation of phagocytic cell biology and pathology. Key words: alternative activation, classical activation, oxidized dextran, peritoneal macrophages, phagocytosis, C57Bl/6J, PMJ2-R