T-lymphocytes are a type of lymphocyte whose primary role is to participate in the maintenance of normal immune function in the body. T-lymphocytes are differentiated from lymphoid stem cells in the thymus and are the most numerous and functionally complex group of lymphocytes. T-lymphocytes are the body’s main immune cells and play an important role in the immune function against disease.T-lymphocytes are also divided into helper lymphocytes and killer lymphocytes, each of which has a different function. Helper lymphocytes can assist other T lymphocytes in recognizing antigens and exercise the function of secondary immunity. Killer lymphocytes are important immune cells in the human body, which are related to the immune regulation of anti-infection, anti-tumor, hypersensitivity, autoimmune diseases and so on. Therefore, T-lymphocytes, as the most important immune cells in the human body, play a very important role in the immune function of the human body. For specific knowledge, please consult a hematologist.