Estabelecimento de linhagens primárias de cultura de células: isolamento, diferenciação e polarização de monócitos da medula óssea de camundongos Balb/c

Abstract

The world has undergone a transition in its patterns of death and morbidity, shifting from a predominance of communicable and infectious diseases to chronic diseases. This process is known as Health Transition, a complex concept that describes changes in health in line with global modernization. The National Cancer Institute (INCA) states that cancer is the second leading cause of death among Brazilians. Understanding the immune system and how its cells interact with chronic pathologies like cancer is fundamental to promoting the utilization of these cells for the body's defense. Innate immunity is our body's first line of defense. Macrophages, as innate immune cells and antigen-presenting cells (APCs), bridge innate and adaptive immunity by presenting antigens associated with MHC Class II to CD4+ T lymphocytes. The tumor microenvironment (TME) is the tumor ecosystem that interacts with non-tumor cells, such as macrophages, leading these cells to exhibit immunosuppressive and pro-tumoral activity. Pro-inflammatory M1-type macrophages are associated with a better prognosis in cancer cases compared to the presence of anti-inflammatory M2-type macrophages. Exposure of monocytes to granulocyte-macrophage colony-stimulating factor (GM-CSF) and Interferon-gamma (IFN-γ) induces polarization towards a pro-inflammatory phenotype. This study aimed to establish a protocol for the differentiation and polarization of macrophages derived from mouse bone marrow cells. We isolated bone marrow cells from albino BALb/c mice, then differentiated them into macrophages using GM-CSF and treated these cells with LPS + IFN-γ. To confirm differentiation, morphological analysis showed a morphology similar to M1-type macrophages, and flow cytometry revealed a significant increase in CD68+ cells in the group exposed to GM-CSF and treated with LPS + IFN-γ. We concluded that the implemented protocol is effective in capturing bone marrow stem cells and differentiating them into the macrophage lineage.