USE OF CROSS-REACTIVE ANTIGENS OF THE MICROSPORIDIAN GLUGEA-ATHERINAEFOR THE POSSIBLE DETECTION OF ENTEROCYTOZOON-BIENEUSI BY WESTERN-BLOT

The microsporidia Enterocytozoon bieneusi is reported in 10-30% of tho se infected with the human immunodeficiency virus. The parasite appear s to be a cause of gastralgia, malabsorption, and diarrhea. A Western blot technique using another microsporidian species, Glugea atherinae, has demonstrated an antigenic similarity between this parasite and E. bieneusi. Preliminary results show the variability of the antigenic p rofiles obtained from the sera of immunodeficient patients infected wi th E. bieneusi and also of the cross-reactivity to Glugea sp. antigens of some sera from patients with cryptosporidiosis. The origin of this cross-reactivity is undetermined. The possibility of coinfection with undetected microsporidia is not excluded. These results raise questio ns concerning the interpretation of serologic data and of the potentia l immunodiagnostic value of microsporidian antigens.