RT Journal Article SR Electronic T1 Streptavidin: A Novel Immunostimulant for the Selection and Delivery of Autologous and Syngeneic Tumor Vaccines JF Cancer Immunology Research JO Cancer Immunol Res FD American Association for Cancer Research SP 469 OP 479 DO 10.1158/2326-6066.CIR-13-0157 VO 2 IS 5 A1 Weir, Chris A1 Hudson, Amanda L. A1 Moon, Elizabeth A1 Ross, Angus A1 Alexander, Miles A1 Peters, Lyndsay A1 Langova, Veronika A1 Clarke, Stephen J. A1 Pavlakis, Nick A1 Davey, Ross A1 Howell, Viive M. YR 2014 UL http://cancerimmunolres.aacrjournals.org/content/2/5/469.abstract AB Induction of antitumor immunity using autologous tumor proteins is an attractive approach to cancer therapy. However, better methods and stimulants to present these autologous proteins back to the immune system are needed. Here, we identify streptavidin as a novel carrier protein and stimulant, and test the efficacy of both syngeneic (rat) and autologous vaccines (dogs) using streptavidin in combination with reduced soluble tumor proteins. Initial syngeneic vaccine studies in the 9L rat glioma model were used to optimize vaccine dose and selectivity. Cytokine and blood analysis was used to monitor the response. Rats receiving two vaccinations of syngeneic tumor vaccine demonstrated a statistically significant (P < 0.05) survival advantage compared with controls (adjuvant only). Notably, vaccination also led to remission rates of between 30% and 60% in the aggressive 9L glioma model. Antibodies to streptavidin were detected in the serum of vaccinated rats; however, antibody levels did not correlate with the response. The cytokine TNF-α was upregulated in vaccine-treated rats, whereas ICAM1 was downregulated. After engraftment, vaccinated rats maintained CD4+, CD8+ T cells, and total lymphocyte levels closer to normal baseline than those in the controls. Twenty-five dogs treated with autologous vaccine preparations using streptavidin as a stimulant showed no adverse reactions, irrespective of additional chemotherapy and other medications. In this study, we developed a novel method for producing syngeneic and autologous vaccines using streptavidin selectivity and immunogenicity. These vaccines show efficacy in the 9L glioma rat model. Safety was also demonstrated in canine patients presenting with cancer treated with autologous vaccine. Cancer Immunol Res; 2(5); 469–79. ©2014 AACR.