The correct concept of immunity is

Immunity refers to a protective response of the body's immune system to recognize and remove antigen substances. By resisting and defending the infection of microorganisms or parasites, it maintains the physiological balance of the body and ensures the health of the body. Immunity can be divided into nonspecific immunity and specific immunity. Immunity has the functions of physiological defense, self-stabilization and immune monitoring. If these functions change, it will lead to various diseases. Too high physiological defense can cause allergic reaction, too high self-stability can cause rheumatoid arthritis and autoimmune diseases, and too low immune monitoring can lead to tumors.

Immune function usually refers to the body's resistance to external unfavorable factors. Immune function is mainly manifested in immune prevention, immune stability and immune monitoring, which can effectively eliminate the influence of pathogenic microorganisms and other foreign bodies. Immune function is of great significance to the normal survival and development of human beings. Immune function is mainly accomplished by immune cells. If the immune function is low, it will easily lead to the disorder of human organs and tissues, which will lead to various bad diseases, even incurable diseases and even death in serious cases. Once the human immunity is low, you must go to the hospital for diagnosis in time and take the corresponding drugs under the guidance of a doctor. Don't ignore it, otherwise it will easily worsen the condition and cause adverse harm to human health and life.