PT - JOURNAL ARTICLE AU - Saverio Minucci AU - Benedetta Bussolati AU - Paul E. Massa AU - Alessia Brossa AU - Roberto Ravasio AU - Mona Saadeldin AU - Genny Degani AU - Elli Papadimitriou AU - Amal Saadeldin AU - Antonio Salvaggio AU - Cristina Visintin AU - Giulia Rizzi AU - Stefano Ricagno AU - Laura Popolo AU - Maria Antonietta Vanoni AU - Pier Giuseppe Pelicci TI - Goat PRP14 (gPRP14) has xeno-antigenic properties and works as a vaccine in preclinical models of cancer AID - 10.1101/2022.07.04.498594 DP - 2022 Jan 01 TA - bioRxiv PG - 2022.07.04.498594 4099 - http://biorxiv.org/content/early/2022/07/04/2022.07.04.498594.short 4100 - http://biorxiv.org/content/early/2022/07/04/2022.07.04.498594.full AB - We studied the activity of recombinant goat PRP14 (gPRP14), a member of the RID protein family, as a xeno-antigen in preclinical models of cancer. Antisera from rabbits and mice immunized with gPRP14 showed strong reactivity against several tumor cell types, which was absent towards normal cells: the tumor selectivity was related to surface and intra-cellular expression in tumor cells, and to an exclusively intra-cellular localization in normal cells. In vitro, binding to tumor cells was followed by cytotoxicity which could be rescued by the addition of excess soluble antigen. In vivo, an anti-tumor activity of immunization with gPRP14 was observed in murine syngeneic models of breast cancer and melanoma: the anti-tumor response was present when gPRP14 was administered in a preventive setting, and persisted upon repeated challenges with tumor cells in long-term survivor mice. Finally, we showed that both the humoral and T-cell mediated responses are needed for the optimal anti-tumor effect in the murine melanoma model. Thus, we have performed an initial characterization of gPRP14 as a cancer vaccine, which -given the potential wide range of tumor cells positive for the antigen-appears as a promising, novel immunotherapy.Competing Interest StatementThe authors have declared no competing interest.