Production and Characterization of Polyclonal Antibodies Specific for Entamoeba histolytica
Ivan Chester G. Canoy1 and Windell L. Rivera1,2*
1Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City
2Molecular Protozoology Laboratory, Natural Sciences Research Institute
University of the Philippines, Diliman, Quezon City
ABSTRACT
Murine polyclonal antibodies (pAbs) were produced by immunizing BALB/c mice with trophozoites of Entamoeba histolytica HK9 in Freund’s adjuvant. Using indirect fluorescent antibody test (IFAT), we have developed polyclonal IgG antibodies that specifically reacted with formalin-fixed E. histolytica trophozoites, but failed to bind with live trophozoites, suggesting the epitope to be cytoplasmic and not cell surface located. Entamoeba dispar, Entamoeba coli, and Blastocystis hominis showed no reactivity with the pAbs. Western immunoblot analysis revealed the reactivity of the pAbs with 95 kDa and 103 kDa major proteins, antigens that we consider as novel as there are no reports to date on these molecules. The pAbs developed in the present study are valuable, particularly when used in IFAT in the accurate detection and differentiation of the pathogenic E. histolytica from the non-invasive E. dispar.
INTRODUCTION
Amebiasis, a disease caused by the enteric protozoan Entamoeba histolytica, is a major public health problem, especially, in developing countries. E. histolytica is responsible for up to 100,000 deaths per year, placing it second only to malaria as a cause of mortality due to protozoan parasites (World Health Organization 1997). Because of this, the detection of E. histolytica is an important goal of the clinical microbiology laboratories throughout the world (Tanyuksel & Petri 2003).
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