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How do macrophages help tissues heal after an infection?

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Immune stimulation by activated helper T cells — immune system Stimulation of immune response by activated helper T cells. Activated by complex interaction with molecules on the surface of a macrophage or some other antigen-presenting cell, a helper T cell proliferates into two general subtypes, T_H1 and T_H2. These in turn stimulate the complex pathways of the cell-mediated immune response and the humoral immune response, respectively.

Macrophages play a critical role in the healing process following an infection by acting as a cleanup crew for the affected area. After arriving at the site of injury, these white blood cells perform the essential task of disposing of cellular debris.1

This debris typically accumulates from two primary sources: tissue cells destroyed during the infection and neutrophils that have self-destructed after ingesting microorganisms. By clearing away these remnants, macrophages help resolve the inflammatory response and prepare the tissue for repair. While macrophages are also known for initiating immune responses and engulfing pathogens, their function in removing waste is vital for restoring tissue integrity once the threat has been neutralized.12