Autoimmunity

Immunity refers to the resistance exhibited by the host towards the injury caused by micro-organisms and their products. Protection against infectious diseases is the only consequence of the immune response, which is directly concerned with the reaction of the body against any foreign antigen. Autoimmunity is when the body's natural defence mistakenly attacks the body's own tissue. It is present in humans to some extent. It is usually harmless & probably a universal phenomenon for human life. The immune mechanism differs from one autoimmune disease to another. Nowadays it is accepted that autoimmune responses are an integral part of vertebrate immune systems.