Citations

Background Tumor-derived small extracellular vesicles were shown to contribute to immunosuppression in various cancer types, including head and neck squamous cell carcinoma. Dendritic cells, major regulators of specific anti-tumor immune response, are often impaired in their function in the context of cancer. Methods Monocyte-derived dendritic cells were incubated with isolated small extracellular vesicles during or after maturation. Cell surface markers and antigen processing machinery were assessed by flow cytometry. Vesicle-treated dendritic cells were tested for interleukin 12p70 production by ELISA, and differences in uptake of labeled vesicles were shown by confocal microscopy. Results Small extracellular vesicles derived from HPV(+) tumor cell lines increased maturation and activation of immature dendritic cells, priming them for more rapid phagocytosis. Immature dendritic cells co-incubated with vesicles had lower levels of antigen presenting machinery components and produced less IL12p70 than controls, while similarly co-incubated mature dendritic cells remained unaffected. Vesicles in plasma of patients with head and neck cancer inhibited functions of mature dendritic cells by downregulating expression of antigen presenting machinery components. Conclusion Our results uncover mechanisms through which tumor-derived small extracellular vesicles modulate dendritic cell functions locally and systemically. These mechanisms may also affect dendritic cell-based vaccine efficacy.

AbstractBackgroundNemolizumab is a humanized anti‐IL‐31 receptor blocker in phase 3 for atopic dermatitis (AD).ObjectiveAnalyse onset of action of nemolizumab 30 mg and compare efficacy and safety vs placebo (SC q4wk plus loading dose) in moderate‐to‐severe AD.MethodsPost hoc analysis of patients with Eczema Area and Severity Index (EASI) scores ≥ 16 from a phase 2b trial of moderate‐to‐severe AD. Endpoints were change in EASI score at week 16, peak pruritus numeric rating scale (PP‐NRS), Investigator’s Global Assessment (IGA), changes in sleep and responders with ≥ 4‐point improvement on PP‐NRS.ResultsThere was a significantly greater itch relief apparent by Day 2 (−22.8% vs –12.3% PP‐NRS; P = 0.005) which continued to improve through week 16 (−68.5% vs −30.9% PP‐NRS; P < 0.001). At week 16, PP‐NRS ≥ 4‐point response of itch was observed in 68.0% nemolizumab vs 15.9% placebo patients (P ≤ 0.001). There was also a rapid improvement of sleep disturbance with nemolizumab 30 mg, with a significant separation from placebo by Day 3 (−26.6% vs –9.0%; P < 0.001) which further improved till week 16 (−76.0% vs −36.5%; P < 0.001). Also for the EASI score a separation between groups in favour of nemolizumab was observed by week 1 (P ≤ 0.001), which increased through week 16 (−68.6% vs. −42.6%; P = 0.002). Finally, the degree of response was greater in nemolizumab‐treated patients; clinically relevant reductions of 75% EASI were observed in 50.0% of nemolizumab patients versus 15.9% of placebo patients, while 90% reductions were reported for 36.0% and 6.8% of patients, respectively (P < 0.001 for both). IGA success (score of 0/1) was 32.0% for nemolizumab vs 6.8% for placebo (P = 0.002).Nemolizumab was safe and well‐tolerated in this population; nasopharyngitis and upper respiratory tract infection were the most common adverse events.ConclusionsNemolizumab resulted in very rapid, sustained improvements of inflammation, pruritus and sleep in patients with EASI ≥ 16 at baseline.

Abstract Immunotherapy is showing promise for otherwise incurable cancers. Oncolytic viruses (OVs), developed as direct cytotoxic agents, mediate their antitumor effects via activation of the immune system. However, OVs also stimulate antiviral immune responses, including the induction of OV-neutralizing antibodies. Current dogma suggests that the presence of preexisting antiviral neutralizing antibodies in patients, or their development during viral therapy, is a barrier to systemic OV delivery, rendering repeat systemic treatments ineffective. However, we have found that human monocytes loaded with preformed reovirus–antibody complexes, in which the reovirus is fully neutralized, deliver functional replicative reovirus to tumor cells, resulting in tumor cell infection and lysis. This delivery mechanism is mediated, at least in part, by antibody receptors (in particular FcγRIII) that mediate uptake and internalization of the reovirus/antibody complexes by the monocytes. This finding has implications for oncolytic virotherapy and for the design of clinical OV treatment strategies. Cancer Immunol Res; 6(10); 1161–73. ©2018 AACR.