MICROANATOMY

Detailed explanation-1: -The helper T-cell becomes activated when the cell encounters an antigen-presenting cell (APC). The helper T-cell stimulates B-cells to produce antibodies, tags the pathogen for phagocytic destruction by macrophages, and activates killer or cytotoxic T-cells.

Detailed explanation-2: -The third line of defense are the specific lymphocytes that produce antibodies as part of the adaptive immune response.

Detailed explanation-3: -What is the body’s third line of defence against pathogens? The third level of your immune system consists of cells tailor-made to get rid of the specific microorganisms that have invaded your tissue. Special cells called dendritic cells are the liaison (point of communication) between innate and adaptive immunity.

Detailed explanation-4: -Innate immune cells are the body’s first line of defense. They quickly respond to foreign cells to fight infection, battle a virus or defend the body against bacteria. T-cells and B-cells react when invading organisms slip through that first line using a process called acquired immunity (or adaptive immunity).