ANATOMY

Detailed explanation-1: -Macrophages and neutrophils (phagocytes) are the front-line defenders in your body’s immune system. They seek out, ingest, and destroy pathogens and other debris through a process called phagocytosis.

Detailed explanation-2: -TH cells stimulate B cells that have engulfed and presented pathogen-derived antigens. B cells differentiate into plasma cells that secrete antibodies, whereas CTLs induce apoptosis in intracellularly infected or cancerous cells. Memory cells persist after a primary exposure to a pathogen.

Detailed explanation-3: -This is called phagocytosis. First, the macrophage surrounds the unwanted particle and sucks it in. Then, the macrophage breaks it down by mixing it with enzymes stored in special sacs called lysosomes. The leftover material is then pushed out of the cell as waste.

Detailed explanation-4: -Phagocytosis is an evolutionarily conserved defense mechanism by which macrophages capture and kill pathogens and remove apoptotic cells into specialized intracellular compartments. Phagocytosis is mediated by scavenger receptors, Fc Receptors (FcRs), and Complement Receptors (CRs) (2).