PATHOLOGY

Detailed explanation-1: -A type of white blood cell, granulocyte, and phagocyte that aids in fighting infection. Neutrophils kill pathogens by ingesting them. Phagocytes eat up pathogens by attaching to and wrapping around the pathogen to engulf it. Once the pathogen is trapped inside the phagocyte, it is in a compartment called a phagosome.

Detailed explanation-2: -Armed effector cytotoxic CD8 T cells are essential in host defense against pathogens that live in the cytosol, the commonest of which are viruses. These cytotoxic T cells can kill any cell harboring such pathogens by recognizing foreign peptides that are transported to the cell surface bound to MHC class I molecules.

Detailed explanation-3: -T cells are designed to recognise the molecular signatures of particular proteins, such as those from bacteria, in order to activate an immune response. Macrophages eat other cells and are able to pull apart their proteins in order to present them to T cells.

Detailed explanation-4: -Macrophages are specialised cells involved in the detection, phagocytosis and destruction of bacteria and other harmful organisms. In addition, they can also present antigens to T cells and initiate inflammation by releasing molecules (known as cytokines) that activate other cells.