Wassermann Test - Method

Method

A sample of blood or cerebrospinal fluid is taken and introduced to the antigen - cardiolipin extracted from bovine muscle or heart. Syphilis non-specific antibodies (reagin, see RPR) react with the lipid - the Wassermann reaction of antiphospholipid antibodies (APAs). The intensity of the reaction (1, 2, 3, or 4) indicates the severity of the condition.

To execute the test we need to prepare two different test tube; in the first tube:

1. we put the serum of the patient, and we heat it to 56°C for 20 minutes (this to eliminate the complement of our patient)
2. we insert the cardiolipin, our antigen
3. we insert fresh rabbit serum (that contain a determined quantity of complement; in this way we can misure exactly the quantity of complement in the test tube)
4. we insert a detector system, composed of mutton blood cells and anti-blood cells antibodies.

In the "control" test tube we insert only the detector system and the fresh rabbit serum.

In our test tube (that contain the serum of our patient), we can observe two tipes of reaction: hemolisis or no hemolisis. In the "control" test tube we ever observe hemolisis (if the rabbit serum and the detector system are effective). If we observe hemolisis it means that no reagine was present in our patient's serum, because the complement of the rabbit was not consummed. Thus when we insert the detector system the complement is able to attack the mutton blood cells. Instead, if the reagins was present in the patient's sierum, the complement is activated and used by reagins; so when we insert the detector system we observe no hemolisis.