Human urine stimulates in vitro growth of Trypanosoma cruzi and Trypanosoma rangeli

Cultivation of monoxenous trypanosomatids: A minireview

Trypanosomatids are obligatory parasites, some of which are responsible for important human and animal diseases, but the vast majority of trypanosomatids are restricted to invertebrate hosts. Isolation and in vitro cultivation of trypanosomatids from insect hosts enable their description, characterization, and subsequently genetic and genomic studies. However, exact nutritional requirements are still unknown for most trypanosomatids and thus very few defined media are available. This mini review provides information about the role of different ingredients, recommendations and advice on essential supplements and important physicochemical parameters of culture media with the aim of facilitating first attempts to cultivate insect-infesting trypanosomatids, with a focus on monoxenous trypanosomatids.

Comparison of camel, dog and the laboratory animals' sera with the fetal calf serum (FCS) for cultivation of Leishmania major

The best-known serum for Leishmania spp. cultivation is the fetal calf serum (FCS), which is very expensive with ethical concerns. This study was conducted to compare various laboratory (BALB/c mice, rat, rabbit, hamster and guinea pig) and non-laboratory (dog and camel) animals' sera as a substitute for FCS in L. major culture. L. major, MRHO/IR/75/ER strain, was cultivated in RPMI-1640 medium enriched with different percentages of mentioned animal's sera. Parasite growth was checked constantly. The rate of growth and survival of parasites were compared with a control medium enriched with FCS. As well, biochemical (albumin, globulin AST, ALT, ALP, Bil, BUN, Crea, Ca, P, Na, K, Fe, TIBC, Mg, zinc, Chol, HDL, LDL, TG, BS, uric acid, LDH, CPK) analysis of all sera was performed and compared with FCS. The most promastigote growth rate is considered in 10% BALB/c, guinea pig and hamster sera on the 6th day of cultivation. Also, on the 8th day, parasites showed viability in all animal sera. The promastigote growth in culture media enriched with the camel and the dog sera in comparison with laboratory animals was considered very low. Differences between 10% FCS and 10% cocktail serum were not significant (p > 0.05) but with other sera were significant (p < 0.05). Also, differences between BALB/c with hamster and guinea pig sera were not significant, respectively (p = 0.07 and p = 0.09). According to the biochemical analysis of all sera, the higher content of iron was detected in the hamster, guinea pig, BALB/c and fetal calf sera. The magnesium and zinc content of guinea pig and BALB/c serum was found to be more than the others and comparable with FCS. The promastigote growth decreased by camel, dog and rat sera orderly. In this study, a rapid increase in parasite growth in media supplemented with hamster, BALB/c and guinea pig sera was considered. It could be suggested to use these sera as a suitable alternative for FCS in molecular biology researches.

Trypanosoma rangeli 28Sβ Ribosomal Gene Allows Intra and Interspecific Molecular Differentiation

Trypanosoma rangeli is an avirulent flagellate protozoan that could mislead correct diagnosis of Trypanosoma cruzi infection, the causative agent of Chagas' disease, given their high similarity. Besides, T. rangeli presents two genetic groups, whose differentiation is achieved mainly by molecular approaches. In this context, ribosomal DNA (rDNA) is a useful target for intra and interspecific molecular differentiation. Analyzing the rDNA of T. rangeli and comparison with other trypanosomatid species, two highly divergent regions (Trβ1 and Trβ2) within the 28Sβ gene were found. Those regions were amplified and sequenced in KP1(+) and KP1(-) strains of T. rangeli, revealing group-specific polymorphisms useful for intraspecific distinction through restriction fragment length polymorphism technique. Also, amplification of Trβ1 allowed differentiation between T. rangeli and T. cruzi. Trβ2 predicted restriction length profile, allowed differentiation between T. rangeli, T. cruzi, Trypanosoma brucei, and Leishmania braziliensis, increasing the use of Trβ1 and Trβ2 beyond a molecular approach for T. rangeli genotyping, but also as a useful target for trypanosomatid classification.

DNA content analysis allows discrimination between Trypanosoma cruzi and Trypanosoma rangeli

Trypanosoma cruzi, a human protozoan parasite, is the causative agent of Chagas disease. Currently the species is divided into six taxonomic groups. The genome of the CL Brener clone has been estimated to be 106.4-110.7 Mb, and DNA content analyses revealed that it is a diploid hybrid clone. Trypanosoma rangeli is a hemoflagellate that has the same reservoirs and vectors as T. cruzi; however, it is non-pathogenic to vertebrate hosts. The haploid genome of T. rangeli was previously estimated to be 24 Mb. The parasitic strains of T. rangeli are divided into KP1(+) and KP1(-). Thus, the objective of this study was to investigate the DNA content in different strains of T. cruzi and T. rangeli by flow cytometry. All T. cruzi and T. rangeli strains yielded cell cycle profiles with clearly identifiable G1-0 (2n) and G2-M (4n) peaks. T. cruzi and T. rangeli genome sizes were estimated using the clone CL Brener and the Leishmania major CC1 as reference cell lines because their genome sequences have been previously determined. The DNA content of T. cruzi strains ranged from 87,41 to 108,16 Mb, and the DNA content of T. rangeli strains ranged from 63,25 Mb to 68,66 Mb. No differences in DNA content were observed between KP1(+) and KP1(-) T. rangeli strains. Cultures containing mixtures of the epimastigote forms of T. cruzi and T. rangeli strains resulted in cell cycle profiles with distinct G1 peaks for strains of each species. These results demonstrate that DNA content analysis by flow cytometry is a reliable technique for discrimination between T. cruzi and T. rangeli isolated from different hosts.

Semisolid liver infusion tryptose supplemented with human urine allows growth and isolation of Trypanosoma cruzi and Trypanosoma rangeli clonal lineages

INTRODUCTION

This work shows that 3% (v/v) human urine (HU) in semisolid Liver Infusion Tryptose (SSL) medium favors the growth of Trypanosoma cruzi and T. rangeli.

METHODS

Parasites were plated as individual or mixed strains on SSL medium and on SSL medium with 3% human urine (SSL-HU). Isolate DNA was analyzed using polymerase chain reaction (PCR) and pulsed-field gel electrophoresis (PFGE).

RESULTS

SSL-HU medium improved clone isolation. PCR revealed that T. cruzi strains predominate on mixed-strain plates. PFGE confirmed that isolated parasites share the same molecular karyotype as parental cell lines.

CONCLUSIONS

SSL-HU medium constitutes a novel tool for obtaining T. cruzi and T. rangeli clonal lineages.

Species-specific markers for the differential diagnosis of Trypanosoma cruzi and Trypanosoma rangeli and polymorphisms detection in Trypanosoma rangeli

Trypanosoma cruzi and Trypanosoma rangeli are kinetoplastid parasites which are able to infect humans in Central and South America. Misdiagnosis between these trypanosomes can be avoided by targeting barcoding sequences or genes of each organism. This work aims to analyze the feasibility of using species-specific markers for identification of intraspecific polymorphisms and as target for diagnostic methods by PCR. Accordingly, primers which are able to specifically detect T. cruzi or T. rangeli genomic DNA were characterized. The use of intergenic regions, generally divergent in the trypanosomatids, and the serine carboxypeptidase gene were successful. Using T. rangeli genomic sequences for the identification of group-specific polymorphisms and a polymorphic AT(n) dinucleotide repeat permitted the classification of the strains into two groups, which are entirely coincident with T. rangeli main lineages, KP1 (+) and KP1 (-), previously determined by kinetoplast DNA (kDNA) characterization. The sequences analyzed totalize 622 bp (382 bp represent a hypothetical protein sequence, and 240 bp represent an anonymous sequence), and of these, 581 (93.3%) are conserved sites and 41 bp (6.7%) are polymorphic, with 9 transitions (21.9%), 2 transversions (4.9%), and 30 (73.2%) insertion/deletion events. Taken together, the species-specific markers analyzed may be useful for the development of new strategies for the accurate diagnosis of infections. Furthermore, the identification of T. rangeli polymorphisms has a direct impact in the understanding of the population structure of this parasite.

Effects of sheep and mouse urine on the growth pattern of Leishmania major promastigotes

The protozoan parasites of the genus Leishmania are the causative agents of different clinical diseases. Fetal calf serum (FCS) is the main part and the most expensive ingredient of the Leishmania culture media. Here, the efficacies of different concentrations (1%, 2.5%, 5%, and 10%) of the filtered and autoclaved sheep and mouse urine were evaluated as a growth stimulator in Leishmania culture procedure. The results indicated that culture media enriched with the filtered sheep and mouse urine supported the growth of the parasites and can be used for cultivation of Leishmania parasites. In conclusion, this study has demonstrated an alternative low-cost medium that could be used in cultivation process of Leishmania major promastigotes.

Effect of human urine on cell cycle and infectivity of Leismania species promastigotes in vitro

In vitro cultivation of Leishmania parasites plays an important role in diagnosis and treatment of leishmaniasis and in vaccine and drug development studies. Conversely, long-term cultivation of Leishmania parasites usually results in decreased infectivity potential. Some studies reported a stimulatory effect of human urine in Leishmania promastigotes. However, there is no information about the effects of urine within culture on the infectivity of Leishmania parasites. Analysis of the effect of urine have showed that proliferation indexes were significantly increased in culture medium supplemented with human urine (L. tropica = 38.17 ± 5.12, L. donovani = 34.74 ± 5.6, L. major = 34.22 ± 4.66, and L. infantum 35.88 ± 6.40) than in controls. Infection indexes were 13 ± 1.7 for L. tropica, 55 ± 2.2 for L. infantum, 41 ± 3.14 for L. donovani, and 49 ± 3.26 for L. major. Our results showed that human urine increased the infectivity and proliferation of Leishmania parasites.

Karyotype variability in KP1(+) and KP1(-) strains of Trypanosoma rangeli isolated in Brazil and Colombia

In the present study, the molecular karyotypes of 12 KP1(+) and KP1(-) Trypanosoma rangeli strains were determined and 10 different molecular markers were hybridized to the chromosomes of the parasite, including seven obtained from T. rangeli [ubiquitin hydrolase (UH), a predicted serine/threonine protein kinase (STK), hexose transporter, hypothetical protein, three anonymous sequences] and three from Trypanosoma cruzi [ubiquitin-conjugating enzyme E2 (UBE2), ribosomal RNA methyltransferase (rRNAmtr), proteasome non-ATPase regulatory subunit 6 (PSMD6)]. Despite intraspecific variation, analysis of the karyotype profiles permitted the division of the T. rangeli strains into two groups coinciding with the KP1(+) and KP1(-) genotypes. Southern blot hybridization showed that, except for the hexose transporter probe, all other probes produced distinct patterns able to differentiate the KP1(+) and KP1(-) genotypes. The UH, STK and An-1A04 probes exclusively hybridized to the chromosomes of KP1(+) strains and can be used as markers of this group. In addition, the UBE2, rRNAmtr and PSMD6 markers, which are present in a conserved region in all trypanosomatid species sequenced so far, co-hybridized to the same T. rangeli chromosomal bands, suggesting the occurrence of gene synteny in these species. The finding of distinct molecular karyotypes in KP1(+) and KP1(-) strains of T. rangeli is noteworthy and might be used as a new approach to the study of genetic variability in this parasite. Together with the Southern blot hybridization results, these findings demonstrate that differences at the kDNA level might be associated with variations in nuclear DNA.