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  • Article: Multiplex bead assay for serum samples from children in Haiti enrolled in a drug study for the treatment of lymphatic filariasis.
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    ABSTRACT: A multiplex bead assay (MBA) was used to analyze serum samples collected longitudinally from children enrolled in a drug trial for treatment of filariasis in Leogane, Haiti. Recombinant antigens Bm14 and Bm33 from Brugia malayi, third polar tube protein (PTP3) from Encephalitozoon cuniculi, and merozoite surface protein-1(19) (MSP-1(19)) from Plasmodium falciparum were coupled to carboxylated polystyrene microspheres. IgG responses to PTP3 and MSP-1(19) were not affected by albendazole (ALB), diethylcarbamazine (DEC), or combination of diethylcarbamazine and albendazole (DEC/ALB). However, IgG and IgG4 responses to Bm14 and Bm33 were significantly decreased (P < 0.001) by DEC and DEC/ALB treatment. Antibody responses to Bm14 and Bm33 decreased after DEC treatment (but not placebo) among children who were negative for microfilaremia and antigenemia at baseline, suggesting that these children harbored early stages of infection. The MBA is an excellent serologic technique for multiple antigens that offers substantial advantages over single-antigen based enzyme-linked immunosorbent assay in mass drug administration studies for monitoring changes in antibody levels.
    The American journal of tropical medicine and hygiene 08/2011; 85(2):229-37. · 2.59 Impact Factor
  • Article: Identification of antigenic targets for immunodetection of Balamuthia mandrillaris infection.
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    ABSTRACT: The free-living amoeba Balamuthia mandrillaris causes granulomatous amoebic encephalitis (GAE) in humans. Rapid identification of balamuthiasis is critical for effective therapeutic intervention and case management. In the present study we identified target antigens for the development of a serological assay for B. mandrillaris infection. We demonstrated by silver staining that protein profiles for all eight isolates of B. mandrillaris, independent of human or animal origin or geographic origin, appeared to be similar except for some minor differences, indicating the molecular homogeneity of these strains. The profiles of all isolates, which ranged from 200 to 10 kDa, were similar, with a prominent protein visible around 30 kDa; all appeared considerably different from protein profiles of the control E6 cells and Acanthamoeba castellanii and Naegleria fowleri isolates. Western blot analysis with rabbit hyperimmune serum identified the major immunodominant antigens of 25, 50, 75, and 80 kDa; positive human sera reacted strongly with proteins around 25, 40, 50, and 75 kDa. Proteins around 40 kDa detected by human serum were not recognized by hyperimmune rabbit serum. None of the target proteins were detected by uninfected control sera. Reactivities of five patients' sera with 4 different isolates of B. mandrillaris (2 strains of human and 2 strains of animal origins) revealed that patients' sera reacted slightly differently with different B. mandrillaris isolates, although major proteins of approximately 25, 50, and 75 kDa were present in all extracts.
    Clinical and vaccine immunology: CVI 06/2011; 18(8):1297-301. · 2.37 Impact Factor
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    Article: Seropositivity for Enterocytozoon bieneusi, Czech Republic.
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    ABSTRACT: To determine seropositivity for Enterocytozoon bieneusi in the Czech Republic, we tested 115 serum samples from various groups. We found that 20% from HIV-positive persons, 33% from persons with occupational exposure to animals, and 10% from healthy persons were positive by indirect immunofluorescence assay. Proteins of 32 kDa were detected in serum samples from seropositive persons.
    Emerging Infectious Diseases 02/2010; 16(2):335-7. · 6.79 Impact Factor
  • Article: Expression and serologic assessment of a recombinant polar tube protein from Encephalitozoon cuniculi (PTP3).
    Journal of Eukaryotic Microbiology 02/2006; 53 Suppl 1:S70-1. · 2.66 Impact Factor
  • Article: Purification of Enterocytozoon bieneusi spores from stool specimens by gradient and cell sorting techniques.
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    ABSTRACT: A three-step method for the purification of Enterocytozoon bieneusi spores from stool specimens was developed. The primary process of purification of the spores from bacterial contaminants involved Percoll gradient centrifugation followed by additional separation using cesium chloride density gradient centrifugation. The cesium chloride-isolated spores were further purified using a flow cytometer with cell sorting capabilities. Sorting was performed without the use of antibodies, fluorochromes, or dyes, leaving the sorted spores in their native state, which appears to be less destructive for spores. When quantified by flow cytometry using tubes with known numbers of highly fluorescent polystyrene beads, the sorted material showed a slight decrease in light scatter characteristics compared with the slightly larger Encephalitozoon species spores. Although the overall recovery of the E. bieneusi spores was low, calcofluor and Gram chromotrope staining, indirect immunofluorescence assay, and transmission electron microscopy revealed that the sorted material was highly purified and contained large numbers of E. bieneusi spores and relatively few bacteria and other debris. The sorted material appeared to be sufficiently pure and could be used for in vitro culture and for the development of a variety of diagnostic reagents as well as in studying the genome of E. bieneusi and host-parasite interactions.
    Journal of Clinical Microbiology 08/2004; 42(7):3256-61. · 4.15 Impact Factor

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