BackgroundColorectal cancer usually gives rise to a specific anti-tumor immune response, but for unknown reasons the resulting immunity is not able to clear the tumor. Recruitment of activated effector lymphocytes to the tumor is important for efficient anti-tumor responses, while the presence of regulatory T cells (Treg) down-modulate tumor-specific immunity. We therefore aimed to determine homing mechanisms and activation stage of Treg and effector T cell infiltrating colon tumors compared to cells from the unaffected mucosa in patients suffering from colon adenocarcinoma.Methodology/Principal FindingsLymphocytes were isolated from unaffected and tumor mucosa from patients with colon adenocarcinoma, and flow cytometry, immunohistochemistry, and quantitative PCR was used to investigate the homing mechanisms and activation stage of infiltrating Treg and conventional lymphocytes. We detected significantly higher frequencies of CD25highFOXP3+CD127low putative Treg in tumors than unaffected mucosa, which had a complete demethylation in the FOXP3 promotor. Tumor-associated Treg had a high expression of CTLA-4, and some appeared to be antigen experienced effector/memory cells based on their expression of αEβ7 (CD103). There were also significantly fewer activated T cells and more CTLA-4+ conventional T cells susceptible to immune regulation in the tumor-associated mucosa. In contrast, CD8+granzyme B+ putative cytotoxic cells were efficiently recruited to the tumors. The frequencies of cells expressing α4β7 and the Th1 associated chemokine receptor CXCR3 were significantly decreased among CD4+ T cells in the tumor, while frequencies of CD4+CCR4+ lymphocytes were significantly increased.Conclusions/SignificanceThis study shows that CCR4+CTLA4hi Treg accumulate in colon tumors, while the frequencies of activated conventional Th1 type T cells are decreased. The altered lymphocyte composition in colon tumors will probably diminish the ability of the immune system to effectively attack tumor cells, and reducing the Treg activity is an important challenge for future immunotherapy protocols.
Transitioning towards renewable energy sources is crucial in mitigating climate change and reducing greenhouse gas emissions. Global energy consumption is expected to increase 50 % by 2050, meaning one of today’s main challenges is complying with those demands without tampering with the uncertainties of global climate change. To address climate change renewable energy sources are essential and wind power plays a great role in the energy matrix. Brazil is one of the front runners in the energy transition, where wind power has expanded since the early 2000’s. The state of Bahia, in Northeastern Brazil, is currently the region where wind energy is expanding the most. However, conflicts related to territoriality and justice aspects are increasing in the state due to the fast-expanding wind energy sector. This study applies document and content analysis to explore the multiple narratives regarding the wind energy expansion in the state of Bahia, Brazil. Framing theory and theories addressing power struggles and conflicts in relation to the energy transition will guide the analysis of the documents included in the material. Based on the analysis of the Bahian case, this study shows that different actors frame the matter of wind energy expansion differently depending on their positionings. Civil society and local perspectives are not present in policies and decision-making processes, including the planning and installation of wind energy parks in the studied case. The results suggest that inclusion and participation of local actors, stakeholders and the civil society is essential to ensure a just and sustainable transition to clean energy sources.
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