B2 [ U ] a situation in which people are peaceful and agree with each other, or when things seem right or suitable together: racial harmony (= good feelings between different races) domestic harmony (= good feelings in the family or home) Imagine a society in which everyone lived together in (perfect) harmony. We must ensure that tourism develops in harmony with the environment.
Once activated, helper T cells start to divide and to produce proteins that activate B and T cells as well as other immune cells. The killer T cell is specialized in attacking cells of the body infected by viruses and sometimes also by bacteria. It can also attack cancer cells. The killer T cell has receptors that are used to search each cell that it meets.
The T helper cells (Th cells) are a type of T cell that play an important role in the immune system, particularly in the adaptive immune system. They help the activity of other immune cells by releasing T cell cytokines.These cells help suppress or regulate immune responses.elper T cells are capable of influencing a variety of immune cells, and the T cell response generated (including the extracellular signals such as cytokines) can be essential for a successful outcome from infection.