ABSTRACT
In this study we examined the diagnostic potential of monoclonal antibodies (MAb) reactive to antigens of adult Brugia malayi, their microfilariae and antigen of Dirofilaria immitis. The MAb of clone 17E10, which were of IgM isotype, reacted to the inner cuticles and internal content of both male and female worms and also to the sheath and internal content of microfilariae in utero. However, these MAb did not react to the sheath of blood circulating microfilariae. The MAb 17E10 produced a smear pattern between 37 to > 200 kDa in the Western blot analysis against a SDS-PAGE separated extract of B. malayi. The epitopes were non-protein in nature as indicated by their resistance to proteinase-K treatment. The MAb 17E10 were applied in a sandwich ELISA to detect filarial antigen in the buffy coat and plasma of patients. We tested patients with different clinical manifestations of brugian filariasis, i.e. microfilaremia (M), lymphangitis (L) and elephantiasis (E), as well as non-symptomatic inhabitants of a filariasis endemic area (NE), and compared them to samples from non-symptomatic inhabitants of disease non-endemic areas (NNE). It was found that 22 of 31 (70.9%) of M, 7 of 13 (53.8%) of L, 2 of 14 (14.2%) of E, 10 of 100 (10.0%) of NE and none (0%) of the NNE were positive for antigenaemia. The assay was also positive in 14 of 15 (93.3%) blood samples from B. malayi microfilaremic cats and in 7 of 7 (100%) blood samples of Dirofilaria immitis microfilaremic dogs. The so-developed test has a high potential for routine diagnosis of active filariasis, for epidemiological studies in both humans and reservoir animals and for monitoring treatment efficacy.
Subject(s)
Animals , Antibodies, Helminth/biosynthesis , Antibodies, Monoclonal/biosynthesis , Antigens, Helminth/analysis , Brugia malayi/isolation & purification , Cat Diseases/diagnosis , Cats , Child , Child, Preschool , Cricetinae , Dirofilaria immitis/isolation & purification , Dirofilariasis/diagnosis , Dog Diseases/diagnosis , Dogs , Filariasis/diagnosis , Humans , Hybridomas , Immunologic Tests , Mice , Mice, Inbred BALB C , RatsABSTRACT
The geographical information system (GIS) and available survey data (both from the Filariasis Annual Reports, 1985-1999 and from the published literature) for the microfilarial infection rates are used to develop the first subdistrict-level endemicity maps of lymphatic filariasis in Narathiwat Province. The maps demonstrated the subdistrict-level geographical distribution of filariasis and the subdistricts at varied degrees of infection rate. The maps also indicate that, since 1985, there was a marked decrease in endemicity at the subdistrict level and in some areas, the infection rates were zero. However, transmission remained in the subdistricts surrounding peat swamp forest (Su-ngai Padi, Paluru, Puyo, Pasemat, Bang Khunthong, and Phron subdistricts). The house locations of infected cases, as well as the vector breeding places were geo-registered and placed as symbolic dots on the base maps obtained from Landsat's Thematic Mapper (TM) 5 and the land use map of Narathiwat to display the distribution of filariasis foci. Of 102 houses mapped, there were 40 houses in primary peat swamp forest (39.22%), 26 in rice fields (25.49%), 15 in fruit orchards (14.70%), 10 in coconut fields (9.80%) and others (10.78%). All the houses were close to the larval habitats presented in the survey. A 2-km buffer zone around the conservation boundary of primary peat swamp forest was created to locate risk areas of filariasis transmission. The buffer zone covered an area of 544.11 km2 and included 88.89% of the houses of infected cases found in 2002. It was able to identify 54 villages located in the buffer area, which might help in the determination of resource needs and resource allocation for filariasis control in Narathiwat Province.