This paper analyzes the influence of the piston effect in the longitudinal ventilation system of subway tunnels using numerical methodologies. This aerodynamic effect, highly complex, three-dimensional and unsteady is modeled using Computational Fluid Dynamics (CFD) in order to simulate and analyze in detail the flow patterns associated to this effect. This approach improves the description provided by typical conventional tools, based on 1-D numerical modeling, and constitutes a useful benchmark for calibrating existing tunnel environment simulation software. For this study, a 3D computational model for a typical subway line between two consecutive stations has been considered. The implemented geometry is a typical configuration that mimics any modern infrastructure with 100 m long stations connected through a two-way tunnel, 500 m in length. The ventilation system is longitudinal, composed of two inlet shafts, with mechanical ventilation for each station, and an exhaust shaft in the middle of the tunnel. Additionally, at the tunnel edges, close to the stations, there are also natural ventilation shafts or draught relief shafts (DRS)-i.e. without mechanical fans-to attenuate possible pressure fluctuations originating from the piston effect. The numerical simulation has been conducted using the commercial code, FLUENT, developing an unsteady numerical model with a dynamic mesh technique to simulate the train displacement between the two stations. Different cases have been studied in detail, including a wide range of ventilation conditions, as well as travel frequencies (single train and two trains crossing halfway). The main objective of this analysis has been the definition and quantification of the different parameters influencing the subway ventilation system. Finally, the impact of the piston effect on the global ventilation performance has also been addressed via numerical estimation. *Manuscript Click here to view linked References [1] Data from Seoul Subway Lines & Stations, with an estimation of the overall energy consumption of the Metro Stations around 70 million kWh/year and 3.75 million users per day.

Preclinical assessment of novel therapies to fight cancer requires models that reflect the human physiology and immune response. Here, we established an in vitro three-dimensional (3D) reconstructed organotypic human melanoma-in-skin (Mel-RhS) model to investigate cellular and molecular features of tumor formation over a period of 6 weeks. Tumor nests developed over time at the epidermal–dermal junction and spread towards the dermis, in places disrupting the basement membrane. This coincided with secretion of matrix metalloproteinase 9 (MMP-9) by melanoma cells. These features resemble the initial stages of invasive melanoma. Interestingly, while the SK-MEL-28 cell line did not secrete detectable levels of interleukin-10 (IL-10) in traditional two-dimensional monolayers, it did express IL-10 in the 3D Mel-RhS, as did the surrounding keratinocytes and fibroblasts. This cellular cross-talk-induced secretion of IL-10 in the Mel-RhS indicated the generation of an immune suppressive microenvironment. Culture supernatants from Mel-RhS interfered with monocyte-to-dendritic-cell differentiation, leading to the development of M2-like macrophages, which was in part prevented by antibody-mediated IL-10 blockade. Indeed, high-dimensional single-cell analysis revealed a shift within the monocyte population away from a CD163+PD-L1+ M2-like phenotype upon IL-10 blockade. Thus, the 3D configuration of the Mel-RhS model revealed a role for IL-10 in immune escape through misdirected myeloid differentiation, which would have been missed in classical monolayer cultures.

Gruijl (2019) Constitutively active GSK3β as a means to bolster dendritic cell functionality in the face of tumour-mediated immune suppression, OncoImmunology,

Immune checkpoint inhibitors have advanced the treatment of melanoma. Nevertheless, a majority of patients are resistant, or develop resistance, to immune checkpoint blockade, which may be related to prevailing immune suppression by myeloid regulatory cells in the tumor microenvironment (TME). ORCA-010 is a novel oncolytic adenovirus that selectively replicates in, and lyses, cancer cells. We previously showed that ORCA-010 can activate melanoma-exposed conventional dendritic cells (cDCs). To study the effect of ORCA-010 on melanoma-conditioned macrophage development, we used an in vitro co-culture model of human monocytes with melanoma cell lines. We observed a selective survival and polarization of monocytes into M2-like macrophages (CD14 + CD80-CD163 +) in co-cultures with cell lines that expressed macrophage colony-stimulating factor. Oncolysis of these melanoma cell lines, effected by ORCA-010, activated the resulting macrophages and converted them to a more proinflammatory state, evidenced by higher levels of PD-L1, CD80, and CD86 and an enhanced capacity to prime allogenic T cells and induce a type-1 T cell response. To assess the effect of ORCA-010 on myeloid subset distribution and activation in vivo, ORCA-010 was intratumorally injected and tested for T cell activation and recruitment in the human adenovirus nonpermissive B16-OVA mouse melanoma model. While systemic PD-1 blockade in this model in itself did not modulate myeloid or T cell subset distribution and activation, when it was preceded by i.t. injection of ORCA-010, this induced an increased rate and activation state of CD8a + cDC1, both in the TME and in the spleen. Observed increased rates of activated CD8 + T cells, expressing CD69 and PD-1, were related to both increased CD8a + cDC1 rates and M1/M2 shifts in tumor and spleen. In conclusion, the myeloid modulatory properties of ORCA-010 in melanoma, resulting in recruitment and activation of T cells, could enhance the antitumor efficacy of PD-1 blockade.