Identification of Differentially Expressed Proteins from Leishmania amazonensis Associated with the Loss of Virulence of the Parasites

Abstract

BackgroundThe present study analyzed whether or not the in vitro cultivation for long periods of time of pre-isolated Leishmania amazonensis from lesions of chronically infected BALB/c mice was able to interfere in the parasites' infectivity using in vivo and in vitro experiments. In addition, the proteins that presented a significant decrease or increase in their protein expression content were identified applying a proteomic approach.Methodology/Principal FindingsParasites were cultured in vitro for 150 days. Aliquots were collected on the day 0 of culture (R0), as well as after ten (R10; 50 days of culture), twenty (R20; 100 days of culture), and thirty (R30; 150 days of culture) passages, and were used to analyze the parasites' in vitro and in vivo infectivity, as well as to perform the proteomic approach. Approximately 837, 967, 935, and 872 spots were found in 2-DE gels prepared from R0, R10, R20, and R30 samples, respectively. A total of 37 spots presented a significant decrease in their intensity of expression, whereas a significant increase in protein content during cultivation could be observed for 19 proteins (both cases >2.0 folds). Some of these identified proteins can be described, such as diagnosis and/or vaccine candidates, while others are involved in the infectivity of Leishmania. It is interesting to note that six proteins, considered hypothetical in Leishmania, showed a significant decrease in their expression and were also identified.Conclusions/SignificanceThe present study contributes to the understanding that the cultivation of parasites over long periods of time may well be related to the possible loss of infectivity of L. amazonensis. The identified proteins that presented a significant decrease in their expression during cultivation, including the hypothetical, may also be related to this loss of parasites' infectivity, and applied in future studies, including vaccine candidates and/or immunotherapeutic targets against leishmaniasis.

Proteomics and Leishmaniasis: Potential Clinical Applications

“…Loss of virulence can also be achieved by axenic culture for many passages . L. amazonensis promastigotes cultured for 10, 20, and 30 passages displayed decrease in macrophage infection and changes in proteome as detected by 2DE . Extended culture led to a decrease in proteins such as TXNPx, malic enzyme, enolase, and carboxypeptidase, enzymes known to be involved in virulence of Leishmania or other pathogens …”

Differentially modulated proteins associated with Leishmaniasis—a systematic review of in-vivo and in-vitro studies

“…infantum ELISA; LC–MS/MS Post infection vs pre infection 19 12 2019 [ 48 ] 12 L . infantum ELISA; RP‐ LC‐MS/MS After infection 168 days vs before infection, 211 days after infection vs before infection and 211 days after infection vs 168 days after infection 15 15 2020 [ 47 ] 13 Proteins of Leishmania Between infective strain L. infantum 2DE; MALDI-TOF/TOF MS Abundance volume ratio in BH 400 strain of L. infantum vs BH 46 strain 32 31 2014 [ 50 ] 14 L. amazonensis IEF; 2DE; ESI-TOF MS/MS; Western blot Day 0 vs day 150 19 37 2014 [ 51 ] 15 L. donovani SDS-PAGE; Nano HPLC–MS/MS; Western blot VL vs CL 29 109 2015 [ 53 ] 16 L. tropica 2DE-MALDI-TOF/TOF MS Percent volume of spot in gel of VL vs CL 10 35 2015 [ 54 ] 17 <...>…”

“…Despite the presence of a similar abundance level of other virulence-related proteins in both BH400 and BH46, the study reported higher signal intensity in the proteins of BH400. On the other hand, Magalhães et al [ 51 ] compared the protein modulations between severe (day 0 of culture) and less virulent (day 150 of culture) L. amazonensis and reported 56 differentially regulated proteins. Out of them, 19 and 37 proteins were up-regulated and down-regulated, respectively.…”

An Insight into the Constitutive Proteome Throughout Leishmania donovani Promastigote Growth and Differentiation

“…Once internalized by phagocytic cells, they differentiate into non-motile amastigotes. The main life cycle stages of several Old World and New World species causing cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL), or VL have been compared using high-throughput gene expression analysis (e.g., Akopyants et al 2004;Alcolea et al 2010;Holzer et al 2006;Magalhaes et al 2014;Saxena et al 2007). Most comparisons are focused on promastigote-intoamastigote development.…”