The Process of Inflammation in a Traumatized Area
The inflammatory response comprises three stages. Initially, arterioles’ vasodilation and increased capillary permeability enhance blood flow. This leads to three inflammatory symptoms: heat, redness, and swelling. Subsequently, neutrophils adhere to blood vessel walls, squeeze through (emigration), and are followed by monocytes transforming into macrophages. These macrophages engulf damaged tissue, worn-out neutrophils, and microbes. Finally, tissue repair begins.
Innate Immunity
The innate immune response is the body's immediate, nonspecific defense mechanism against pathogens. It acts as the first line of defense and includes physical barriers like the skin and mucous membranes, as well as cellular components such as white blood cells (e.g., neutrophils, macrophages) and proteins. When a pathogen breaches these barriers, the innate immune system quickly recognizes and responds, triggering inflammation, activating immune cells to engulf and destroy invaders, and coordinating a rapid defense. Unlike the adaptive immune response, the innate response does not provide long-term immunity and does not specifically target particular pathogens.