Molecular and Proteomic Determinants of Trypanosoma cruzi Adaptation Within Triatomine Vectors: Insights from Current Experimental Models

Trypanosoma cruzi exhibits complex genetic diversity, organized into seven distinct typing units. To complete its life cycle, the parasite must adapt to the digestive tract of various species of triatomine bugs. This systematic review aimed to understand the molecular adaptation mechanisms of T. cruzi in relation to different vector species, systematizing knowledge on vector competence. Following PRISMA guidelines, 18 experimental studies (published between 1995 and 2025) were selected from the ScienceDirect, PubMed, Scopus, and Web of Science databases, focusing on the parasite–vector interface and proteomic analyses. There was a predominance of studies conducted in Brazil (66.67%), using the Rhodnius prolixus model (72.22%) and the TcI strain (clone Dm28c). The evolution of methodological approaches reflects a transition from classical techniques, such as SDS-PAGE, to high-throughput omics strategies, including LC-MS/MS and gene editing tools such as CRISPR. The findings were organized into key biological processes, including parasite adhesion mediated by perimicrovillar membrane components, glycoinositolphospholipids (GIPLs), and mucins; the influence of the metabolic and nutritional microenvironment, particularly hemoglobin-derived peptides and glucose availability; and the role of intestinal redox conditions in triggering metacyclogenesis. Overall, the available evidence suggests that T. cruzi adaptation within triatomine vectors is a multifactorial process driven by proteomic reprogramming and post-transcriptional regulation in response to environmental signals within the vector gut. However, this understanding is largely derived from studies based on Rhodnius prolixus and TcI strains, which limits the generalization of these mechanisms across other triatomine species and parasite lineages.