Deciphering the <em>Fasciola hepatica</em> Glycocode and Its Involvement in Host-Parasite Interactions

The zoonotic disease fasciolosis poses a significant global threat to both humans and livestock. The causative agent of fasciolosis is Fasciola hepatica which is commonly referred to as liver fluke. The emergence of drug resistance has underscored the urgent need for new therapeutic treatments against F. hepatica. The tegument surface of F. hepatica is characterized by a dynamic syncytial layer surrounded by a glycocalyx which serves as a crucial interface in host-parasite interactions, facilitating functions such as nutrient absorption, sensory input, and defense against the host immune response. Despite its pivotal role, only recently have we delved deeper into understanding glycans at the host-parasite interface and the glycosylation of hidden antigens. These glycan antigens have shown promise for vaccine development or as targets for drug manipulation across various pathogenic species. This review aims to consolidate current knowledge on the glycosylation of F. hepatica, exploring glycan motifs identified through generic lectin probing and mass spectrometry. Additionally, it examines the interaction of glycoconjugates with lectins from the innate immune systems of both ruminant and human host species. An enhanced understanding of glycans&#039; role in F. hepatica biology and their critical involvement in host-parasite interactions will be instrumental in developing novel strategies to combat these parasites effectively. In the future, a more comprehensive approach may be adopted in selecting and designing potential vaccine targets, integrating insights from glycosylation studies to improve efficacy.