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Spurred by global COVID‐19, work in recent years has demonstrated that various devices based on technology generating cold plasma are capable of reducing the infectivity of virus particles. There is great potential in this approach, which is, however, hampered by the ability of most cold plasma science laboratories to test for antiviral effects of their individual plasma sources in sophisticated mammalian cell test systems. To this end, we developed a quick, simple, and fast assay system based on bacteriophages and their ability to lyse bacterial hosts, which can be monitored in readily available microplate readers. We successfully demonstrated the principal ability of this approach using two types of plasma jets, different microplate readers, and two different bacteriophage strains. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests the role of reactive oxygen and nitrogen species (RONS) in regulating antitumor immune effects and immunosuppression. RONS modify biomolecules and induce oxidative post‐translational modifications (oxPTM) on proteins that can alarm phagocytes. However, it is unclear if and how protein oxidation by technical means could be a strategy to foster antitumor immunity and therapy. To this end, cold gas plasma technology producing various RONS simultaneously to oxidize the two melanoma‐associated antigens MART and PMEL is utilized. Cold plasma‐oxidized MART (oxMART) and PMEL (oxPMEL) are heavily decorated with oxPTMs as determined by mass spectrometry. Immunization with oxidized MART or PMEL vaccines prior to challenge with viable melanoma cells correlated with significant changes in cytokine secretion and altered T‐cell differentiation of tumor‐infiltrated leukocytes (TILs). oxMART promoted the activity of cytotoxic central memory T‐cells, while oxPMEL led to increased proliferation of cytotoxic effector T‐cells. Similar T‐cell results are observed after incubating splenocytes of tumor‐bearing mice with B16F10 melanoma cells. This study, for the first time, provides evidence of the importance of oxidative modifications of two melanoma‐associated antigens in eliciting anticancer immunity. [ABSTRACT FROM AUTHOR]

Gas plasma is a medical technology with antimicrobial properties. Its main mode of action is oxidative damage via reactive species production. The clinical efficacy of gas plasma-reduced bacterial burden has been shown to be hampered in some cases. Since the reactive species profile produced by gas plasma jets, such as the kINPen used in this study, are thought to determine antimicrobial efficacy, we screened an array of feed gas settings in different types of bacteria. Antimicrobial analysis was performed by single-cell analysis using flow cytometry. We identified humidified feed gas to mediate significantly greater toxicity compared to dry argon and many other gas plasma conditions. The results were confirmed by inhibition zone analysis on gas-plasma-treated microbial lawns grown on agar plates. Our results may have vital implications for clinical wound management and potentially enhance antimicrobial efficacy of medical gas plasma therapy in patient treatment. [ABSTRACT FROM AUTHOR]

Plasma medicine is a developing field that utilizes the effects of cold physical plasma on biological substrates for therapeutic purposes. Approved plasma technology is frequently used in clinics to treat chronic wounds and skin infections. One mode of action responsible for beneficial effects in patients is the potent antimicrobial activity of cold plasma systems, which is linked to their unique generation of a plethora of reactive oxygen and nitrogen species (ROS). During the SARS-CoV-2 pandemic, it became increasingly clear that societies need novel ways of passive and active protection from viral airway infections. Plasma technology may be suitable for superficial virus inactivation. Employing an optimized neon-driven micro plasma jet, treatment time-dependent ROS production and cytotoxic effects to different degrees were found in four different human cell lines with respect to their metabolic activity and viability. Using the murine hepatitis virus (MHV), a taxonomic relative of human coronaviruses, plasma exposure drastically reduced the number of infected murine fibroblasts by up to 3000-fold. Direct plasma contact (conductive) with the target maximized ROS production, cytotoxicity, and antiviral activity compared to non-conductive treatment with the remote gas phase only. Strikingly, antioxidant pretreatment reduced but not abrogated conductive plasma exposure effects, pointing to potential non-ROS-related mechanisms of antiviral activity. In summary, an optimized micro plasma jet showed antiviral activity and cytotoxicity in human cells, which was in part ROS-dependent. Further studies using more complex tissue models are needed to identify a safe dose-effect window of antiviral activity at modest toxicity. [Display omitted] • The biological effects of novel micro plasma jet suitable for endoscopic applications is presented. • In vitro cytotoxicity in four cell lines was dominated by long-lived gas plasma-derived products such as hydrogen peroxide. • Antiviral gas plasma activity against a murine coronavirus was shown, caused by short but not long-lived reactive species. • TheRemote reactive species deposition was far less antiviral than the gas plasma jet in direct contact with viral suspensions. [ABSTRACT FROM AUTHOR]

Despite continuous advances in therapy, cancer remains a deadly disease. Over the past years, gas plasma technology emerged as a novel tool to target tumors, especially skin. Another promising anticancer approach are nanoparticles. Since combination therapies are becoming increasingly relevant in oncology, both gas plasma treatment and nanoparticle exposure were combined. A series of nanoparticles were investigated in parallel, namely, silica, silver, iron oxide, cerium oxide, titanium oxide, and iron-doped titanium oxide. For gas plasma treatment, the atmospheric pressure argon plasma jet kINPen was utilized. Using three melanoma cell lines, the two murine non-metastatic B16F0 and metastatic B16F10 cells and the human metastatic B-Raf mutant cell line SK-MEL-28, the combined cytotoxicity of both approaches was identified. The combined cytotoxicity of gas plasma treatment and nanoparticle exposure was consistent across all three cell lines for silica, silver, iron oxide, and cerium oxide. In contrast, for titanium oxide and iron-doped titanium oxide, significantly combined cytotoxicity was only observed in B16F10 cells. [ABSTRACT FROM AUTHOR]