Macrophages are important cells of the immune system that are formed in response to an infection or accumulating damaged or dead cells. When macrophages are exposed to inflammatory stimuli, they secrete cytokines such as tumor necrosis factor (TNF), IL-1, IL-6, IL-8, and IL-12. Although monocytes and macrophages are the main sources of these cytokines, they are also produced by activated lymphocytes, endothelial cells, and fibroblasts.

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拍攝者： 7activestudio