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

Abstract

Previous studies conducted in Leishmania led us to test the hypothesis that addition of human urine (HU) to the Liver Infusion Tryptose (LIT) medium would stimulate the in vitro growth of Trypanosoma cruzi and Trypanosoma rangeli strains. Herein, we show that the addition of 3% HU to LIT medium (LIT-HU3) significantly stimulated the growth of all the T. rangeli strains studied when compared with the parasite growth in conventional LIT medium (p<0.05), and it was equivalent to the growth observed in LIT supplemented with fetal calf serum (FCS) in two parasite strains. Four out of the six T. cruzi strains analyzed showed a significant increase in parasite multiplication in LIT-HU3 (p<0.05). However, two parasite strains presented good growth in both LIT and LIT-HU, suggesting differences in the parasite's ability to grow in vitro. Furthermore, we have not observed differences in T. cruzi growth in LIT-HU3 and LIT supplemented with heat-denatured HU and in the metacyclogenesis of parasite strains cultured in LIT-HU3. These results allow concluding that the addition of HU to LIT medium stimulates the in vitro growth of T. rangeli and T. cruzi and can replace FCS as a supplement in culture medium.

Effect of Human Urine on Cell Cycle and Infectivity of Leismania Species Promastigotes In Vitro

“…36 In a study of Trypanosoma cruzi and T. rangeli , an increase in the number of infective tripomastigotes was detected in urine-containing culture. 37 In our study, infectivity of Leishmania promastigotes increased in cultures containing urine compared with control cultures that did not contain urine. Results were similar to the effects of urine in cultures of Trypanosoma spp.…”

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

“…In our study, the difference in time required for colony appearance between T. cruzi (approximately 12 days) and T. rangeli (21 days) explains the reason that T. cruzi colonies predominate on mixed plates. Differences in the growth curves of T. cruzi and T. rangeli have been described previously (5) and may explain the presence of only T. cruzi colonies on mixed T. cruzi/T. rangeli plates.…”

“…In liquid media, the addition of HU leads to similar growth rates of T. cruzi and T. rangeli when they are independently cultivated (5) . HU has also been successfully used for cultivation of several Leishmania spp.…”

“…Liver infusion tryptose (LIT) is a liquid medium (4) used for large-scale cultivation of trypanosomatids for genetic characterization and manipulation of parasites. Due to poor growth of T. rangeli in LIT (5) , other supplements must be added to the culture media. The addition of human urine (HU) to LIT medium stimulates the in vitro growth of T. cruzi and T. rangeli, allowing similar maximum parasite densities for these parasites (5) .…”

“…SSL medium was prepared by mixing equal volumes of 2X LIT medium and 2% (w/v) noble agar (Sigma, Missouri, USA). SSL-HU medium was prepared by supplementing SSL with 3% (v/v) sterile HU (5) . Noble agar was replaced with 1% (w/v) bacteriological agar (BA) to produce SSL-BA medium with or without HU.…”