Evaluation of cardiolipin antigen in routine Wassermann reactions.

Cardiolipin is a phospholipid and was isolated by Pangborn (1941, 1942) while investigating the nature of the antigenic material in beef heart muscle used in the Wassermann reaction. It was shown that cardiolipin was serologically active when used together with lecithin, and that the sensitivity of the reaction was enhanced by the addition of cholesterol. A monograph on cardiolipin antigen was published by Pangborn and others (1951), and details of this antigen and methods of preparation are given. Many publications discuss the value of cardiolipin antigen in complement-fixation tests (CFT) and flocculation tests, and most workers have made a strong case for the adoption of this antigen in order to obtain greater sensitivity and specificity in these tests. Mazzini (1951) describes a microflocculation cardiolipin test, and writes that a vast improvement in sero-diagnostic procedures has been made with this antigen, but that there is a tendency to zonal reactions. Lundback and Allander (1951) point out that cardiolipin-lecithin-cholesterol antigen is superior to the old crude extract with regard to specificity and probably to sensitivity as well. Vogelsang and Haaland (1951) also note that cardiolipin antigen is more specific and offers certain advantages when applied to complementfixation and flocculation tests. The following published reports are also in favour of cardiolipin antigens, particularly with regard to increased specificity and sensitivity: Chronicle of the World Health Organization (1951), Joulia and Pautrizel (1951a, b), Flynn, Tompkins, and Beecher (1952), and Steigner (1954). Guthe and Willcox (1954) write, " the more specific cardiolipin antigens have now been accepted everywhere as the antigens of choice in the sero-diagnosis of syphilis ". Rappaport and Eichhorn (1951) used a tube flocculation method with three different formulae for the cardiolipin antigen and obtained practically identical results in specificity and sensitivity. Giordano, Shively, and Bahler (1952) compared cardiolipin