Differential diagnosis of Taenia saginata and Taenia solium infections: From DNA probes to polymerase chain reaction
Por:
González L.M., Montero E., Sciutto E., Harrison L.J.S., Parkhouse R.M.E., Garate T.
Publicada:
1 ene 2002
Resumen:
The objective of this work was the rapid and easy differential diagnosis of Taenia saginata and T. solium. First, a T. saginata size-selected genomic deoxyribonucleic acid (gDNA) library was constructed in the vector ?gt10 using the 2-4 kb fraction from the parasite DNA digested with EcoR1, under 'star' conditions. After differential screening of the library and hybridization analysis with DNA from T. saginata, T. solium, T. taeniaeformis, T. crassiceps, and Echinococcus granulosus (bovine, porcine, and human), 2 recombinant phages were selected. They were designated HDP1 and HDP2. HDP1 reacted specifically with T. saginata DNA, and HDP2 recognized DNA from both T. saginata and T. solium. The 2 DNA probes were then sequenced and further characterized. HDP1 was a repetitive sequence with a 53 bp monomeric unit repeated 24 times in direct tandem along the 1272 bp fragment, while the 3954 bp HDP2 was not a repetitive sequence. Using the sequencing data, oligonucleotides were designed and used in a polymerase chain reaction (PCR). The 2 selected oligonucleotides from probe HDP1 (PTs4F1 and PTs4R1) specifically amplified gDNA from T. saginata, but not T. solium or other related cestodes, with a sensitivity of <10 pg of T. saginata gDNA, about the quantity of DNA in one taeniid egg. The 3 oligonucleotides selected from the HDP2 sequence (PTs7S35F1, PTs7S35F2, and PTs7S35R1) allowed the differential amplification of gDNA from T. saginata, T. solium and E. granulosus in a multiplex PCR, again with a sensitivity of <10 pg. These diagnostic tools have immediate application in the differential diagnosis of T. solium and T. saginata in humans and in the diagnosis of dubious cysts in the slaughterhouse. We also hope to apply them to epidemiological surveys of, for example, soil and water in endemic areas.
Filiaciones:
González L.M.:
Ministerio De Sanidad Y Consumo, Instituto De Salud Carlos III, Centro Nacional De Microbiologia, Madrid, Spain
Montero E.:
Ministerio De Sanidad Y Consumo, Instituto De Salud Carlos III, Centro Nacional De Microbiologia, Madrid, Spain
Sciutto E.:
Departamento De Inmunologia, Instituto De Investigaciones Biomédicas, Universidad Autónoma De México, Mexico, DF, Mexico
Harrison L.J.S.:
University of Edinburgh, Centre for Tropical Veterinary Medicine, Easter Bush, Roslin, Midlothian, United Kingdom
University of Edinburgh, Centre for Tropical Veterinary Medicine, Easter Bush, Roslin, Midlothian, EH25 9RG, United Kingdom
Parkhouse R.M.E.:
Gulbenkian Institute for Science, Oeiras, Portugal
Garate T.:
Ministerio De Sanidad Y Consumo, Instituto De Salud Carlos III, Centro Nacional De Microbiologia, Madrid, Spain
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