Inhibitors
An inhibitor can be understood as an immune system response to infused clotting factor concentrates, an inhibitor renders standard replacement therapy ineffective. It is estimated that 1/3 to 1/5 of people with severe hemophilia A as well as 1% to 4% of those with severe hemophilia B might sometimes develop an inhibitor. The body attempts to protect itself from disease with a host of defenses, these defenses are collectively called the immune system. The first line defense of the immune system are the barriers, which includes the skin and mucus membranes. However, the immune system is not the body's sole defense. Once a pathogen has made its way past these barriers, the body increases a cellular immune response. This cellular response results in antibody production. People with hemophilia might not produce the coagulation protein needed in the process of coagulation. Therefore in some cases, a replacement factor might be administered, the body's immune system sometimes perceive the normal clotting factor as an pathogen and cellular response is activated. These antibodies are referred to as inhibitors.