Differential detection of Blastocrithidia triatomae and Trypanosoma cruzi by amplification of 24salpha ribosomal RNA genes in faeces of sylvatic triatomine species from rural northwestern Argentina.
Flagellates indistinguishable from Trypanosoma cruzi were detected by microscopy in faecal samples of 2/110 Triatoma guasayana and 2/283 Triatoma garciabesi captured in a rural area of northwestern Argentina. Inoculation of faecal homogenates to mice followed by xenodiagnosis, haemoculture, histopathology and culture from cardiac homogenates, and PCR based on T. cruzi minicircle and nuclear sequences failed to detect T. cruzi infection, pointing to another trypanosomatidean. A PCR strategy targeted to the D7 domain of 24salpha ribosomal DNA genes amplified a 250 bp sequence from one T. guasayana and one T. garciabesi faecal lysate. Sequence analysis revealed 100% identity with 24salpha rDNA amplicons from Blastocrithidia triatomae obtained from faeces of reared Triatoma infestans bugs. Phylogenetic analysis clustered this sequence with C. fasciculata and L. major, separated from the Trypanosoma branch (bootstrap: 968/1000), in concordance with a Neighbour-joining dendrogram based on 18s rDNA sequences. This PCR procedure provides a rapid sensitive tool for differential diagnosis of morphologically similar trypanosomatids in field surveys of Chagas disease vectors and laboratory-reared triatomines used for xenodiagnosis.
Schijman
A G
AG
Laboratorio de Biología Molecular de la Enfermedad de Chagas, Instituto de Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Buenos Aires, Argentina. schijman@dna.uba.ar
Lauricella
M A
MA
Marcet
P L
PL
Duffy
T
T
Cardinal
M V
MV
Bisio
M
M
Levin
M J
MJ
Kitron
U
U
Gürtler
R E
RE
D000818:Animals; D001118:Argentina; D001483:Base Sequence; D018105:DNA, Kinetoplast / Q000737:chemistry / Q000235:genetics; D005243:Feces / Q000469:parasitology; D007303:Insect Vectors / Q000469:parasitology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012335:RNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D012424:Rural Population; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014224:Triatoma / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D014351:Trypanosomatina / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D020525:Xenodiagnosis
D018105:DNA, Kinetoplast; D012335:RNA, Ribosomal