Mapping the distribution of immune cells in various mouse tissues

The immune system is complex machinery where various interactions between immune cells via cell signaling, hormones, and chemokines lead to differentiation of the immune cell. With each interaction that causes immune cells to differentiate, the cellular properties will undergo modification where cells will express different cell surface markers, synthesize different proteins, gain, or lose a function, or start proliferation. By utilizing the changes in cell surface markers, it is possible to categorize immune cells and accurately identify the type of immune cells within a mice tissue which will be the focus of this project. The particular interest in this research is to identify M1 and M2 cells, and myeloid-derived suppressor cells. M1 (CD45+CD11b+F4/80+CD80+CD163-) cells are classically known as activated macrophages, and as a histiocyte, it phagocytoses pathogens and generates reactive oxygenated species. It is activated by pro-inflammatory cytokines such as IFN-y, TNF-a, or LPS, and it is activated by TH1. M2 (CD45+CD11b+F4/80+CD206+) cells are noted for their anti-inflammatory properties and promote tissue repair and wound healing. Myeloid-derived suppressor cells (MDSCs), on the other hand, are noted for their immunosuppressive effects. Mouse G-MDSCs (CD11b+Ly6G+Ly6Clo) suppresses immune responses in an antigen-specific manner via the production of reactive oxygenated species while mouse M-MDSCs (CD11b+Ly6G-Ly6Chi) suppresses immune responses in both antigen-specific and non-specific manners via synthesis of reactive oxygenated species. One of the hallmarks of MDSCs is that it is one of the cells that are found early in tumor progression. During the tumor formation, there is a notable increase in extramedullary hematopoiesis, neutrophilia, presence of abnormal myeloid cells which lack the membrane marks of known immune cells which are now identified as MDSCs. As this research will be a part of multi-part research, mapping the mouse immune cell tissue distribution will be utilized to build a foundation and set up an initial data for comparison for later when we start looking at mice with cancers and ones that are treated with chemotherapy. This will help us to easily identify the recruitment/loss/differentiation of immune cells caused by any systemic changes.