31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

ULMUS CRASSIFOLIA (ULMACEAE) IN FLORIDA

Volume: 3Start Page: 115End Page: 11

TRILLIUM PUSILLUM (LILIACEAE) IN MISSISSIPPI

Volume: 8Start Page: 209End Page: 21

NOTES ON NOTEWORTHY RECORDS OF CAREX (CYPERACEAE) FROM THE SOUTHEASTERN UNITED STATES

Volume: 15Start Page: 125End Page: 13

OCCURRENCE, DISTRIBUTION, AND ECOLOGY OF ALOCASIA, CALADIUM, COLOCASIA, AND XANTHOSOMA (ARACEAE) IN THE SOUTHEASTERN UNITED STATES

Volume: 19Start Page: 149End Page: 17

08. The Oculus Rift VR Enhances Mindfulness Practice Adjunctive Treatment

In modern society, technology is often thought of as a distraction, but the purpose of this study was to observe if technology could be utilized to aid in mindfulness practice. We examined the effect of virtual reality (VR) on mindfulness to assess levels of nonjudgement, awareness, and attention. We used an Oculus Rift (Facebook Technologies, LLC) ©, the Perfect (NDreams) © virtual reality environment, and the Hill’s Mindfulness Practice (HMP) © auditory training instructions, created by the authors. Participants were randomly selected into three conditions over a six-session trial: a VR group with mindfulness training, an auditory mindfulness group, and a VR control group. A significant main effect on nonjudgement showed an increase in scores, F (1, 32) = 5.75, p = .02, ηp2 = .15. The mindfulness control group had the same amount of time awareness in the first session and significantly lower awareness for sessions two through six, F (10,160) = 2.69, p = .02, ηp2 = .12. There was a main effect of calmness between training groups, F (2, 32) = 6.211, p = .005, ηp2 = .28. The VR control (M = 6.83, SD = .32) showed significantly lower reports of calmness than the mindfulness control (M = 7.79, SD = .31) and mindfulness VR groups (M = 8.40, SD = .31) which did not differ. Together, these findings could be used to help college students learn to be present in the moment and maintain awareness in their everyday life. Key Words: Mindfulness, virtual reality, technology, awareness, attention, nonjudgemen