The antigenic composition and protein profiles of eumycetoma agents

The protein profiles of different eumycetoma agents were compared by SDS gel electrophoresis. Dendrograms confirmed the homogeneity of isolates of Pseudallescheria boydii but amongst Madurella species, particularly isolates identified as M. grisea, there were substantial differences in protein composition. However using Western blotting reference isolates of the different species showed distinct antigen patterns in response to immune rabbit sera. In particular there was little evidence of cross reactivity between M. mycetomatis and M. grisea. However this specificity was not apparent when human sera from patients with different eumycetoma infections were compared in an ELISA system using the same antigens. It is possible that the formation of a mycetoma grain may limit a patient's exposure to antigens which confer specificity, an explanation which may also account for the variability in antibody responses seen.