Membrane associated proteins of two Trichomonas gallinae clones vary with the virulence

Abstract

Oropharyngeal avian trichomonosis is mainly caused by Trichomonas gallinae, a protozoan parasite that affects the upper digestive tract of birds. Lesions of the disease are characterized by severe inflammation which may result in fatality by starvation. Two genotypes of T. gallinae were found to be widely distributed in different bird species all over the world. Differences in the host distribution and association with lesions of both genotypes have been reported. However, so far no distinct virulence factors of this parasite have been described and studies might suffer from possible co-infections of different genotypes. Therefore, in this paper, we analyzed the virulence capacity of seven clones of the parasite, established by micromanipulation, representing the two most frequent genotypes. Clones of both genotypes caused the maximum score of virulence at day 3 post-inoculation in LMH cells, although significant higher cytopathogenic score was found in ITS-OBT-Tg-1 genotype clones at days 1 and 2, as compared to clones with ITS-OBT-Tg-2. By using one representative clone of each genotype, a comparative proteomic analysis of the membrane proteins enriched fraction has been carried out by a label free approach (Data available via ProteomeXchange: PXD013115). The analysis resulted in 302 proteins of varying abundance. In the clone with the highest initial virulence, proteins related to cell adhesion, such as an immuno-dominant variable surface antigen, a GP63-like protein, an armadillo/beta-catenin-like repeat protein were found more abundant. Additionally, Ras superfamily proteins and calmodulins were more abundant, which might be related to an increased activity in the cytoskeleton re-organization. On the contrary, in the clone with the lowest initial virulence, larger numbers of the identified proteins were related to the carbohydrate metabolism. The results of the present work deliver substantial differences between both clones that could be related to feeding processes and morphological changes, similarly to the closely related pathogen Trichomonas vaginalis.

Proteomic signatures of metronidazole-resistant Trichomonas vaginalis reveal novel proteins associated with drug resistance

“…Additionally, differentially expressed proteins were identified from bovine and feline Tritrichomonas foetus genotypes, providing evidence of host-specific adaptation [28]. A recent comparative proteomic analysis of the membrane proteins has been carried out in another trichomonad Trichomonas gallinae, showing distinct proteins associated with virulence [29].…”

To get sick or not to get sick—Trichomonas infections in two Accipiter species from Germany

“…However, Amin et al ( 2012 ) found a correlation of peptidase activity and virulence in chicken liver cell culture and a recent study from Martínez-Herrero et al ( 2019 ) found that membrane-associated proteins vary with virulence and some of the identified proteins are described to be potential virulence factors, similar to their orthologs in T. vaginalis , yet the classification of trichomonad isolates as pathogenic or non-pathogenic is still mainly based on the severity of the symptoms induced in the host (Amin et al 2014 ). Our results indicate that the identification of virulent strains due to the widely used molecular markers does not seem sufficient and the susceptibility of the host seems to be an important factor to consider and studies might suffer from possible co-infections of different genotypes (Martínez-Herrero et al 2019 ). While we did not find a difference in virulence of single strains, being infected with more than one strain did increase the risk to develop clinical signs of trichomonosis in our study.…”

“…Even though genetic data indicate some variation between isolates, no correlation with virulence is yet established (Gerhold et al 2008;Grabensteiner et al 2010;Ecco et al 2012;Stimmelmayr et al 2012) and there is no molecular marker or molecular assay to distinguish virulent from non-virulent strains (Forrester and Foster 2008). However, Amin et al (2012) found a correlation of peptidase activity and virulence in chicken liver cell culture and a recent study from Martínez-Herrero et al (2019) found that membraneassociated proteins vary with virulence and some of the identified proteins are described to be potential virulence factors, similar to their orthologs in T. vaginalis, yet the classification of trichomonad isolates as pathogenic or non-pathogenic is still mainly based on the severity of the symptoms induced in the host (Amin et al 2014). Our results indicate that the identification of virulent strains due to the widely used molecular markers does not seem sufficient and the susceptibility of the host seems to be an important factor to consider and studies might suffer from possible co-infections of different genotypes (Martínez-Herrero et al 2019).…”

In-depth comparative analysis of Tritrichomonas foetus transcriptomics reveals novel genes linked with adaptation to feline host

“…Thus, we do not rule out the role of GP63-like metalloproteases in feline T. foetus infection. Additionally, in Trichomonas gallinarum, GP63-like and subtilisin-like proteases were proposed as virulence determinants 61 . In this context, we suggested a potential role of cysteine proteases (papain and calpain), serine proteases (subtilisin-like proteases) and metalloproteases (GP63-like) as pathogenic factors and potential biomarkers for feline T. foetus.…”