Guilherme Drescher1, Hulyana Brum2, Thiago Bousquet Bandini2, Fabiano Borges Figueiredo1, Michel Batista2
Fasciola hepatica, a zoonotic liver fluke, causes significant economic losses in Brazilian livestock and poses a public health risk due to fasciolosis. Its F. hepatica excretory/secretory (FhES) products and F. hepatica somatic antigen (FhSA) are critical for host-parasite interactions, immune evasion, and adaptation to diverse environmental conditions. Despite the availability of flukicidal medications, re-infection and increasing resistance to different medicaments necessitate novel management measures. Understanding the molecular processes regulating the intricate relationship with the mammalian host may yield significant insights, facilitating the identification of new targets for the diagnosis and management of fasciolosis. Parasite survival in the mammalian host is mediated by parasite compounds released during infection, known as FhES. FhES products are believed to shield parasites from host reactions, enabling prolonged survival inside the vertebrate host. This study investigates proteomic differences in FhES products and FhSA of F. hepatica from distinct Brazilian regions to elucidate molecular adaptations and their implications for control strategies. The aim of the work was characterizing and compare the proteomic profiles of FhES products and FhSA from F. hepatica isolates collected in different regions of Parana state – Brazil. Between November 2024 and March 2025, 46 samples of fluke and FhES products were collected from 23 municipalities in different regions of the state of Paraná. Each sample for somatic antigens consisted of three parasites collected from the same bovine animal, and the parasites were stored in PBS at -80°C. For the FhES products, three parasites were cultured in RPMI medium (2 mL/parasite) for 6 to 8 hours, the supernatant was collected, concentrated using an Amicon 3 kDa filter®, and stored at -80°C. Proteins were separated by SDS-PAGE and identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Preliminary analysis has shown that 60 different proteins have been identified in FhES products. Two conditions were tested for the somatic antigen. The first condition was carried out using three whole flukes, where protein extraction and proteomics were carried out, in which more than 1200 distinct proteins were identified. The second condition was that three flukes were sectioned into three portions (mouth apparatus, body, and final portion); proteomics was carried out separately for each of the portions, and the results were 1300, 1600, and 1800 different proteins, respectively. These extensive data of the FhES products and FhSA obtained from flukes of the different regions of the Paraná state, Brazil, can help to understand F. hepatica biology, key metabolic and molecular mechanism and the search for new drug or vaccine interventions.
Agradecimentos: Carlos Chagas Instituto - ICC, Fiocruz - Paraná