Cellular and molecular basis of antitumor response associated with parasites antigens

FARRÉ, CECILIA; COCORDANO, NABILA; BISCARI, LUCÍA; CAMBRONERA, PAULA; MENACHO MÁRQUEZ, MAURICIO; ALLOATTI, ANDRÉS

Congreso; LXVII Reunión científica anual de la Sociedad Argentina de Inmunología; 2019

In recent years, immunotherapy has emerged as a promising line of research in thedevelopment of antitumor treatments, whose purpose is to restore and/or enhance the abilityof the immune system to effectively combat neoplastic cells. It has long been known thatparasitic infections may affect tumor growth. In particular, Trypanosoma cruzi (causative agentof Chagas disease) presents a series of antigens with antiangiogenic and antitumor properties.Among the possible reasons why parasitic antigens derived from T. cruzi could interfere withtumor growth, both innate and adaptive immunity might participate. However, cellular andmolecular bases of this process are still unknown. Our preliminary results suggest that BALB/cmice infected with T. cruzi show delayed growth of 4T1 tumor, associated with an increase incellular immunity.To elucidate the mechanisms involved, we immunized BALB/c mice with antigen formulations(protein concentration: 1mg/ml) derived from: T. cruzi epimastigotes; T. cruzi tripomastigotes;4T1 tumor cells or PBS as control. Additionally, we planned two different experimentalschemes, immunizing mice before (prophylactic approach) and after (therapeutic) tumorinoculation (n=7 for each group). Whereas the therapeutic approach did not show significantdifferences with the control group, the prophylactic scheme (in particular antigen formulationsof parasite origin) significantly delayed tumor growth and increased survival. Differences werealso significant when analyzing percentages of CD8+ T cells in spleen (p