Monoclonal antibodies for the
coprological diagnosis of microsporidiosis.
Trichrom stain, Weber
By courtesy of M. Thellier and S. Biligui
Enterocytozoon bieneusi and Encephalitozoon intestinalis are important opportunistic pathogens. These intracellular
protists, predominantly infect the epithelium of the small intestine causing chronic
diarrhoea and malabsorption in acquired immunodeficiency syndrome or after organ transplantation in recipients treated with powerful
The most common microsporidial infection in humans is caused by E. bieneusi. There is a high prevalence of enteric carriage of
E. bieneusi amongst immunocompetent persons in tropical countries. This parasite naturally persists in the human population. Double infections with the two parasites might also occur.
In recent years, clinical cases caused by microsporidia decreased due to the administration of highly antiretroviral therapy (HAART) which restores immunity. However, microsporidian parasites are not eliminated in all patients and relapses could be observed. Otherwise, healthy persons, especially travelers returning from tropical areas and
immunosuppressed patients undergoing organ-transplantation are still at threat of such opportunistic infection.
Stool examination for the diagnosis of microsporidial infections currently uses special staining techniques (Weber, Uvitex 2B), which requires a high level of expertise in order to be reliable, and PCR, which is expensive and time consuming. We supply here two monoclonal antibodies specific for
E. bieneusi spores (1.3 x 0.7
mm) and E. intestinalis
spores (1.7 x 1.0 - 1.1 mm)
developed to screen stools by indirect immunofluorescence assay. This diagnostic method showed to be reliable, rapid and specific for the diagnosis and epidemiological survey of microsporidiosis.
Species identification has been possible only using transmission electron microscopy or PCR. The two monoclonal antibodies enable identification of both species. Differentiation between the two intestinal microsporidia is required for an adequate therapy management.
E. intestinalis infections are treated with albendazole, while fumagillin has been shown to be effective for eradicating
E. bieneusi. Thus, species identification is important for defining the appropriate treatment.
2 x 0.5 ml anti-Enterocytozoon bieneusi
monoclonal antibody, ready to use
2 x 0.5 ml anti-Encephalitozoon intestinalis
monoclonal antibody, ready to use
1 x 2.0 ml anti-mouse IgG Alexafluor 488 conjugate, ready to use
Instructions for use (staining procedure)
Sensitivities and specificities:
A sensitivity close to 100 % and a specificity
better than those of specific staining methods (Weber and Uvitex 2B) were
observed using the monoclonal antibodies and IFA.
Simple species diagnosis of human intestinal microsporidia by an immunofluorescence test using specific monoclonal antibodies : an evaluation study in two hospitals in France. M. Thellier, I. Accoceberry , I. Desportes, S. Biligui, E. Bart-Delabesse, C. Ripert, M. Danis, A. Datry. . First United Workshop on Microsporidia from Invertebrate and Vertebreate Hosts (NATO). July 12-15,2004. Ceské Budéjovice.
European directive 98/79/EC registration
Material Safety Data Sheet: Eng
Bordier Affinity Products SA, Chatanerie 2,
CH-1023 Crissier, Switzerland
Phone: + 41 21 633 31 67. Fax: + 41 21
31 78. Email: cb(at)bordier.ch