Cruzipain Promotes Trypanosoma cruzi Adhesion to Rhodnius prolixus Midgut

Abstract

Background Trypanosoma cruzi is the etiological agent of Chagas' disease. Cysteine peptidases are relevant to several aspects of the T. cruzi life cycle and are implicated in parasite-mammalian host relationships. However, little is known about the factors that contribute to the parasite-insect host interaction.Methodology/Principal FindingsHere, we have investigated whether cruzipain could be involved in the interaction of T. cruzi with the invertebrate host. We analyzed the effect of treatment of T. cruzi epimastigotes with anti-cruzipain antibodies or with a panel of cysteine peptidase inhibitors (cystatin, antipain, E-64, leupeptin, iodocetamide or CA-074-OMe) on parasite adhesion to Rhodnius prolixus posterior midgut ex vivo. All treatments, with the exception of CA074-OMe, significantly decreased parasite adhesion to R. prolixus midgut. Cystatin presented a dose-dependent reduction on the adhesion. Comparison of the adhesion rate among several T. cruzi isolates revealed that the G isolate, which naturally possesses low levels of active cruzipain, adhered to a lesser extent in comparison to Dm28c, Y and CL Brener isolates. Transgenic epimastigotes overexpressing an endogenous cruzipain inhibitor (pCHAG), chagasin, and that have reduced levels of active cruzipain adhered to the insect gut 73% less than the wild-type parasites. The adhesion of pCHAG parasites was partially restored by the addition of exogenous cruzipain. In vivo colonization experiments revealed low levels of pCHAG parasites in comparison to wild-type. Parasites isolated after passage in the insect presented a drastic enhancement in the expression of surface cruzipain.Conclusions/SignificanceThese data highlight, for the first time, that cruzipain contributes to the interaction of T. cruzi with the insect host.

Susceptibility of Phytomonas serpens to calpain inhibitors in vitro: interference on the proliferation, ultrastructure, cysteine peptidase expression and interaction with the invertebrate host

“…The expression of surface gp63-like molecules in the insect trypanosomatid Herpetomonas samuelpessoai was drastically enhanced after passage in the insect host model Aedes aegypti gut (Branquinha et al 2013). In addition, T. cruzi cells isolated after passage in the insect vector R. prolixus presented a drastic increase in the expression of surface cruzipain (Uehara et al 2012). Although the interaction step was not performed in vivo, our results revealed that a significant increase in the surface gp63-like and cruzipain-like expression was detected, which is very suggestive of their involvement in the interaction process of the parasite with the invertebrate vector.…”

Untangling the transmission dynamics of primary and secondary vectors of Trypanosoma cruzi in Colombia: parasite infection, feeding sources and discrete typing units

“…In the interpretation, since no T. cruzi DNA quantitation was performed, it is interpreted as positive DNA amplification in Cts < 38 and negative amplification as absence. 12S subunit ribosomal gene of triatomines was used as internal amplification control under the conditions and primers previously described [19]. Subsequently, the insects with positive results by qPCR were submitted to kinetoplast DNA amplification using primers 121 (5′-AAA TAA TGT ACG GGK GAG ATG CAT GA-3′) and 122 (5′-GGT TCG ATT GGG GTT GGT GTA ATA TA-3′) to discriminate T. cruzi and T. rangeli infections as previously reported [20].…”

Decoding the Anti-Trypanosoma cruzi Action of HIV Peptidase Inhibitors Using Epimastigotes as a Model

“…After the blood meal and trypomastigote-into-epimastigote differentiation, T. cruzi epimastigotes migrate to the gut of the insect vector, where they divide and adhere strongly to perimicrovillar membranes in the posterior midgut [52] . The adhesion process of epimastigotes to these membranes is modulated by the participation of glycoconjugates exposed on the surface of the parasite, as glycoinositol phospholipids (GIPLs) and cruzipain [53] , [54] , but several proteins found in perimicrovillar membranes appear to be involved in this process as well [52] . However, the participation of other parasite surface molecules, such as gp72 [55] , mucins [56] and Tcgp63 [57] cannot be excluded.…”