ANATOMY

Detailed explanation-1: -Helper T cells are arguably the most important cells in adaptive immunity, as they are required for almost all adaptive immune responses. They not only help activate B cells to secrete antibodies and macrophages to destroy ingested microbes, but they also help activate cytotoxic T cells to kill infected target cells.

Detailed explanation-2: -B lymphocytes, also called B cells, create a type of protein called an antibody. These antibodies bind to pathogens or to foreign substances, such as toxins, to neutralize them. For example, an antibody can bind to a virus, which prevents it from entering a normal cell and causing infection.

Detailed explanation-3: -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-4: -Naive T-cells are being presented with antigens by the macrophages which “instruct” T-cells on what type of cells to target (such as cancer cells) and kill. During this interaction, T-cells can play a role in immune system homeostasis (Andersen, 2018) by killing the macrophage presenting the antigen.

Detailed explanation-5: -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.