A novel application for non-thermal plasma is the induction of immunogenic cancer cell death for cancer immunotherapy. Cells undergoing immunogenic death emit danger signals which facilitate anti-tumor immune responses. Although pathways leading to immunogenic cell death are not fully understood; oxidative stress is considered to be part of the underlying mechanism. Here; we studied the interaction between dielectric barrier discharge plasma and cancer cells for oxidative stress-mediated immunogenic cell death. We assessed changes to the intracellular oxidative environment after plasma treatment and correlated it to emission of two danger signals: surface-exposed calreticulin and secreted adenosine triphosphate. Plasma-generated reactive oxygen and charged species were recognized as the major effectors of immunogenic cell death. Chemical attenuators of intracellular reactive oxygen species successfully abrogated oxidative stress following plasma treatment and modulated the emission of surface-exposed calreticulin. Secreted danger signals from cells undergoing immunogenic death enhanced the anti-tumor activity of macrophages. This study demonstrated that plasma triggers immunogenic cell death through oxidative stress pathways and highlights its potential development for cancer immunotherapy.

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West Nile virus (WNV) is an emerging mosquito-borne flavivirus, related to dengue virus and Zika virus. To gain insight into host pathways involved in WNV infection, we performed a systematic affinity-tag purification mass spectrometry (AP-MS) study to identify 259 WNV-interacting human proteins. RNAi screening revealed 26 genes that both interact with WNV proteins and influence WNV infection. We found that WNV, dengue and Zika virus capsids interact with a conserved subset of proteins that impact infection. These include the exon-junction complex (EJC) recycling factor, PYM1, which is antiviral against all three viruses. The EJC has roles in nonsense-mediated decay (NMD), and we found that both the EJC and NMD are antiviral and the EJC protein RBM8A directly binds WNV RNA. To counteract this, flavivirus infection inhibits NMD and the capsid-PYM1 interaction interferes with EJC protein function and localization. Depletion of PYM1 attenuates RBM8A binding to viral RNA, suggesting that WNV sequesters PYM1 to protect viral RNA from decay. Together, these data suggest a complex interplay between the virus and host in regulating NMD and the EJC.

Several have shown plasma to be efficacious against cancer cells in vitro and in vivo with minimal damage to non-cancerous cells and tissue. Most are focused on direct influence of plasma on tumor cells. However, the body's immune system also plays a crucial role in the control of cancer. A new concept of immunogenic cell death (ICD) has been emerging, where through this modality of cell death, an immune response may be stimulated. The goal of the presented study was to explore a regime of plasma treatment that induces ICD in tumor cells and stimulates anti-tumor effects in macrophages-a key immune cell type involved in the initiation of immunological responses. Here, we show that treatment with uniform nanosecond pulsed dielectric barrier discharge (nspDBD) plasma directly activated anti-tumor effects in macrophages. We further show macrophage activation following the expression of plasma-induced damage-associated molecular patterns (DAMPs) in tumor cells, characteristic of ICD.

IMPORTANCE Low-socioeconomic urban children often do not have access to ophthalmic care.OBJECTIVE To characterize the demographic characteristics and ophthalmic conditions in children attending Give Kids Sight Day (GKSD), an outreach ophthalmic care program held annually in Philadelphia, Pennsylvania, providing vision screening and immediate treatment when needed. DESIGN, SETTING, AND PARTICIPANTSRetrospective case-series study of children attending GKSD in 2012 (GKSD 2012) at an ophthalmology center in Philadelphia. Registration forms and records of all children attending GKSD 2012 were reviewed.MAIN OUTCOMES AND MEASURES Demographic characteristics, insurance status, spoken languages, reasons for attending, prior failure of vision screening, and attendance pattern of previous events were analyzed. The ophthalmological findings of these children were examined, including refractive errors, need for optical correction, and diagnoses for which continuous ophthalmic care was necessary. For children who needed ophthalmic follow-up, the rate of return to clinic and barriers for continuous care were analyzed. RESULTSWe studied 924 children (mean age, 9 years; age range, 0-18 years; 51% female; 25% speaking a non-English language) coming from 584 families who attended GKSD 2012, of whom 27% were uninsured and 10% were not aware of their insurance status. Forty-two percent of participants had public insurance, which covered vision care and glasses, but 35% did not know their benefits and did not realize vision care was covered. Forty-nine percent of children attended because they failed community vision screening. Provision of free glasses and failure of previous vision screening were the most common reasons families elected to attend GKSD (64% and 49%, respectively). Eighty-five percent of children attended GKSD 2012 for the first time, whereas 15% attended prior events. Glasses were provided to 61% of attendees. Ten percent of the attendees needed continuous ophthalmic care, most commonly for amblyopia. Ten children needed ocular surgery for cataract, strabismus, nystagmus, ptosis, or nasolacrimal duct obstruction. With the assistance of a social worker, 59% of children requiring continuous treatment returned to the clinic, compared with 2% in prior years before social worker intervention. CONCLUSIONS AND RELEVANCEPrograms such as GKSD can bridge the gap between successful vision screening and ophthalmic treatment, a gap that often occurs in low-socioeconomic urban populations. Those with public insurance coverage for vision services may not realize these services are covered. Social worker intervention is useful in overcoming common barriers to follow-up care.