PATHOLOGY

Detailed explanation-1: -The macrophages and neutrophils of the innate immune system provide a first line of defense against many common microorganisms and are essential for the control of common bacterial infections. However, they cannot always eliminate infectious organisms, and there are some pathogens that they cannot recognize.

Detailed explanation-2: -Neutrophils are considered the first responders of the innate immune system. Neutrophils and macrophages circulate though the blood and reside in tissues watching for potential problems. Both cells can “eat” bacteria, as well as communicate with other immune cells if an issue arises.

Detailed explanation-3: -The first cells to arrive, usually within an hour, are neutrophils and eosinophils, followed a few hours later by macrophages.

Detailed explanation-4: -Some types of white blood cells, called phagocytes (FAH-guh-sytes), chew up invading organisms. Others, called lymphocytes (LIM-fuh-sytes), help the body remember the invaders and destroy them.

Detailed explanation-5: -Besides phagocytosis, macrophages play a central role in inflammation. They initiate the immune response against microorganisms, since macrophages are some of the first cells to come in contact with these invaders.