 Illustration shows a capillary near the surface of skin that has a cut in it. Bacteria have penetrated the skin around the cut. In response, mass cells in the lower part of the skin tissue release histamines, and dendritic cells release cytokines. The histamines cause the capillary to become permeable. Neutrophils and monocytes exit the capillary into the damaged skin. Both the neutrophil and macrophage release cytokines and consumes bacteria by phagocytosis.