title: Detection and differentiation of filarial parasites by universal primers and polymerase chain reaction-restriction fragment length polymorphism analysis.
abstract: Filarial nematode parasites are a serious cause of morbidity in humans and animals. Identification of filarial infection using traditional morphologic criteria can be difficult and lead to misdiagnosis. We report on a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)-based method to detect and differentiate a broad range of filarial species in a single PCR. The first internal transcribed spacer 1 (ITS1) along with the flanking 18S and 5.8S ribosomal DNA (rDNA) were isolated and cloned from Wuchereria bancrofti, Brugia malayi, and Brugia pahangi. Sequence analysis identified conserved sites in the 18S and 5.8S rDNA sequence that could be used as universal priming sites to generate ITS1-distinctive PCR products that were useful for distinguishing filariae at the genus level. The addition of a digestion of the ITS1 PCR product with the restriction endonuclease Ase I generated a fragment profile that allowed differentiation down to the species level for W. bancrofti, B. malayi, B. pahangi, Dirofilaria immitis, and D. repens. The PCR-RFLP of ITS1 rDNA will be useful in diagnosing and differentiating filarial parasites in human, animal reservoir hosts, and mosquito vectors in disease-endemic areas.
authors.affiliation: Lymphatic Filariasis Research Unit, Department of Parasitology and Department of Pediatrics, Chula Medical Research Center, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. fmedstt@md2.md.chula.ac.th
authors.forename: Surang
authors.initials: S
authors.lastname: Nuchprayoon
authors.forename: Alisa
authors.initials: A
authors.lastname: Junpee
authors.forename: Yong
authors.initials: Y
authors.lastname: Poovorawan
authors.forename: Alan L
authors.initials: AL
authors.lastname: Scott
mesh_terms: D000818:Animals; D001483:Base Sequence; D017178:Brugia malayi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D017179:Brugia pahangi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D017931:DNA Primers; D018509:DNA, Helminth / Q000008:administration & dosage; D021903:DNA, Ribosomal Spacer / Q000032:analysis; D004182:Dirofilaria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D005368:Filariasis / Q000175:diagnosis* / Q000469:parasitology; D005370:Filarioidea / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012340:RNA, Ribosomal, 5.8S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014958:Wuchereria bancrofti / Q000145:classification / Q000235:genetics / Q000302:isolation & purification
chemical_list: D017931:DNA Primers; D018509:DNA, Helminth; D021903:DNA, Ribosomal Spacer; D012337:RNA, Ribosomal, 18S; D012340:RNA, Ribosomal, 5.8S