A comparison of four major antigens in five human and several animal strains of ureaplasmas.

A comparison of the antigens of single representatives of five serotypes of Ureaplasma urealyticum, of three strains of U. diversum and of single ureaplasmal strains from four other animal hosts was performed by immunoblotting with monoclonal antibodies and a urease 'enzyme-catch test'. The U. urealyticum serotype 8-specific, surface-expressed, 96-Kda antigen was not found in any of the strains of non-human origin. Differences in the distribution of 16- and 17-Kda antigens were also seen, not only between seroclusters A and B of U. urealyticum, but also with respect to animal strains. Five distinct epitopes were expressed on the urease from U. urealyticum and from chimpanzee ureaplasmal strains, but between one and three of these epitopes were either poorly expressed or not detected on the urease from the other animal strains. Apart from lacking the 96-Kda antigen of U. urealyticum serotype 8, chimpanzee strains gave results similar to those obtained with serocluster A of U. urealyticum. The results with the marmoset strain differed from those of all other non-human strains.