TP antibodies refer to antibodies to syphilis spirochetes and the normal range is for those who have not been infected with syphilis spirochetes and antibodies against syphilis spirochetes are unlikely to be present in the blood circulation. If the antigen test for syphilis spirochetes is used, there can be no agglutination reaction and a positive result is not possible. Therefore, such a test is called a specific test for syphilis spirochetes, and is usually performed using the particle agglutination test for syphilis spirochetes, or TPPA, which is negative in normal people. However, there are also clinical methods of testing by non-syphilis spirochete antigens, which can be positive for syphilis patients, but also for non-syphilis spirochete infected people, i.e. normal people, who can sometimes have positive results. Therefore, this test cannot be used to simply determine that the person is infected with syphilis, and if the test is positive, it should also be determined by a TPPA test.