A lineage-specific rapid diagnostic test (Chagas Sero K-SeT) identifies Brazilian Trypanosoma cruzi II/V/VI reservoir hosts among diverse mammalian orders

Abstract

Trypanosoma cruzi, the protozoan agent of Chagas disease in the Americas, is comprised of six genetic lineages (TcI-TcVI) and a possible seventh (TcBat, related to TcI). Identification of T. cruzi lineages infecting reservoir mammalian species is fundamental to resolving transmission cycles. However, this is hindered by the limited sensitivity and technical complexity of parasite isolation and genotyping. An alternative approach is serology using T. cruzi lineage-specific epitopes, such as those of the trypomastigote small surface antigen (TSSA). For surveillance of T. cruzi lineage infections in mammal species from diverse Brazilian regions, we apply a novel rapid diagnostic test (RDT, Chagas Sero K-SeT), which incorporates the TSSA peptide epitope specific to TcII/V/VI (TSSApep-II/V/VI) and Protein G detection of antibodies. Chagas Sero K-SeT RDT results with sera from experimentally infected mice, from tamarin primates (Leontopithecus spp.) and from canines (Canis familiaris) were concordant with corresponding TSSApep-II/V/VI ELISAs. The Chagas Sero K-Set detected TcII/V/VI infections in Leontopithecus spp. from the Atlantic forest (n = 46), in C. familiaris (n = 16) and Thrichomys laurentius (n = 2) from Caatinga biome and Chiroptera (n = 1) from Acre, Amazonia. The Chagas Sero K-SeT RDT is directly applicable to TcII/V/ VI-specific serological surveillance of T. cruzi infection in several different mammalian Orders. It can replace ELISAs and provides efficient, point-of-sampling, low-cost detection of TcII/V/VI infections, with at least equivalent sensitivity, although some mammals may be difficult to trap, and, not unexpectedly, Chagas Sero K-SeT could not recognise feline IgG. Knowledge of sylvatic hosts of T. cruzi can be expanded, new reservoir species discovered, and the ecology of transmission cycles clarified, particularly with adaptation to further mammalian Orders.

Parasites of Free-Ranging and Captive American Primates: A Systematic Review

“…Some studies on Blastocystis assessed the genetic variability and host specificity, reporting different subtypes (ST1-ST5, ST8) [42,61,116]. Studies on Trypanosoma cruzi identified the genetic lineages of the parasite (TcI-TcIII, TcV, TcVI) [64,90] as well as types of Toxoplasma gondii (Type I, Type II, non-archetypal) [39,100]. Molecular approaches were less frequent in studies of nematodes: Trypanoxyuris sp., Dipetalonema sp., Mansonella sp., Brugia sp., Pterygodermatites sp.…”

Glycosylation of Trypanosoma cruzi TcI antigen reveals recognition by chagasic sera

“…Availability of gTSSA-I serology enables parallel investigation of clinical status associated with TcI infection, and serological detection of sporadic TcII/V/VI and TcI co-infections, which occur in some Bolivian and Brazilian endemic foci 40 , 41 . As with application of TSSA-II/V/VI serology to sylvatic mammals 20 , 21 , 23 , 42 , 43 , gTSSA-I can be deployed for resolution of TcI domestic and sylvatic transmission cycles, and for discovery of reservoir hosts. Thus, expression of L. tarentolae recombinant antigens representing epitopes specific to each of the T. cruzi lineages, may facilitate comprehensive epidemiological investigations.…”

“…cruzi trypomastigote small surface antigen (TSSA), a cell surface mucin, have been identified for all six genetic lineages, with the hybrid lineages TcV and TcVI having two epitopes encoded at the heterozygous locus, one of which is shared with TcII, as shown by Bhattacharyya et al 18 . Lineage-specific serology with synthetic peptides representing the TcII/V/VI and TcV/VI epitopes enabled surveillance of chagasic patients 19 , and the discovery of reservoir hosts 20 , 21 . Furthermore, TcII/V/VI serology, adaptable to rapid diagnostic test (RDT) format, demonstrated that among Bolivian patients stratified by severity of cardiomyopathy, TcII/V/VI seropositives were five-fold more prevalent in the severe versus no evidence of cardiomyopathy groups 22 .…”

Nontuberculous Mycobacteria Prevalence in Bats’ Guano from Caves and Attics of Buildings Studied by Culture and qPCR Examinations

“…Bats are well known for being reservoirs for many different pathogenic agents [1][2][3]. Most of the recent interest in this field has been focused on viruses [4][5][6][7], however bats can also host a wide range of fungi [8,9], and protozoa [10,11]. While knowledge of presence of different pathogens in bats continues to grow, very little is known about the pathogenicity of bacteria in bats [2,12].…”