Transcriptomic Analysis Comparing Tumor-Associated Neutrophils with Granulocytic Myeloid-Derived Suppressor Cells and Normal Neutrophils

The role of myeloid cells in supporting cancer growth is well established. Most work has focused on myeloid-derived suppressor cells (MDSC) that accumulate in tumor-bearing animals, but tumor-associated neutrophils (TAN) are also known to be capable of augmenting tumor growth. However, little is known about their evolution, phenotype, and relationship to naïve neutrophils (NN) and to the granulocytic fraction of MDSC (G-MDSC)

Commercial products for osteochondral tissue repair and regeneration

The osteochondral tissue represents a complex structure composed of four interconnected structures, namely hyaline cartilage, a thin layer of calcified cartilage, subchondral bone, and cancellous bone. Due to the several difficulties associated with its repair and regeneration, researchers have developed several studies aiming to restore the native tissue, some of which had led to tissue-engineered commercial products. In this sense, this chapter discusses the good manufacturing practices, regulatory medical conditions and challenges on clinical translations that should be fulfilled regarding the safety and efficacy of the new commercialized products. Furthermore, we review the current osteochondral products that are currently being marketed and applied in the clinical setting, emphasizing the advantages and difficulties of each one.FROnTHERA (NORTE-01-0145- FEDER-000023), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). The authors would also like to acknowledge H2020-MSCA-RISE program, as this work is part of developments carried out in BAMOS project, funded by the European Union’s Horizon 2020 research and innovation program under grant agreement N° 734156. The financial support from the Portuguese Foundation for Science and Technology under the program Investigador FCT 2012 and 2015 (IF/00423/2012 and IF/01285/2015)info:eu-repo/semantics/publishedVersio

Transcriptional Profiling of Lipopolysaccharide-Induced Acute Lung Injury

Mortality associated with acute lung injury (ALI) induced by lipopolysaccharide (LPS) remains high in humans, warranting improved treatment and prevention strategies. ALI is characterized by the expression of proinflammatory mediators and extensive neutrophil influx into the lung, followed by severe lung damage. Understanding the pathogenesis of LPS-induced ALI is a prerequisite for designing better therapeutic strategies. In the present study, we used microarrays to gain a global view of the transcriptional responses of the lung to LPS in a mouse model of ALI that mimics ALI in humans. A total of 71 inflammation-associated genes were up-regulated in LPS-treated lungs, including a chemokine, LPS-induced CXC chemokine (LIX), whose role in the induction of ALI is unknown. Most of the inflammatory genes peaked at 2 h post-LPS treatment. Real-time reverse transcription-PCR confirmed the LPS-induced up-regulation of selected genes identified by microarray analysis, including LIX. The up-regulation of LIX, tumor necrosis factor alpha, and macrophage inflammatory protein 2 was confirmed at the protein level by enzyme-linked immunosorbent assays. To determine the role of LIX in the induction of ALI, we used both exogenous LIX and a LIX blocking antibody. Exogenous LIX alone elicited a neutrophil influx in the lungs, and the anti-LIX antibody attenuated the LPS-induced neutrophil accumulation in the lungs. Taken together, the results of our study demonstrate for the first time the temporal expression of inflammatory genes during LPS-induced ALI and suggest that early therapeutic intervention is crucial to attenuate lung damage. Moreover, we identified a role for LIX in the induction of ALI, and therefore LIX may serve as a novel therapeutic target for the minimization of ALI

Myeloid Differentiation Protein-2–Dependent and –Independent Neutrophil Accumulation during Escherichia coli Pneumonia

Bacterial pneumonia remains a serious disease. Pattern recognition receptors play an integral role in neutrophil accumulation during pneumonia. Although myeloid differentiation protein (MD)-2 has been recognized as a key molecule for LPS signaling, the role of MD-2 in neutrophil accumulation in the lung during bacterial infection has not been explored. Here, we investigate the role of MD-2 in Escherichia coli LPS–induced lung inflammation and E. coli–induced pneumonia. LPS-induced CD14-independent neutrophil accumulation was abolished in CD14/MD-2−/− mice. MD-2−/− mice challenged with LPS displayed attenuated neutrophil influx, NF-κB activation, cytokine/chemokine expression, and lung histopathology. MD-2−/− mice transplanted with MD-2+/+ bone marrow demonstrated decreased neutrophil influx and cytokine/chemokine expression in the lungs when challenged by LPS. MD-2−/− mice infected with E. coli demonstrated reduced neutrophil influx and cytokine/chemokine expression in the lungs, whereas heat-killed E. coli did not induce either neutrophil accumulation or cytokine/chemokine expression in MD-2−/− mice infected with E. coli. Furthermore, MD-2−/− mice displayed increased bacterial burden in the lungs and enhanced bacterial dissemination. Toll-like receptor (TLR)-5−/− mice infected with E. coli exhibited attenuated neutrophil accumulation, whereas MD-2/TLR5−/− mice inoculated with E. coli showed further attenuated neutrophil influx and impaired bacterial clearance. Taken together, these new findings demonstrate: (1) the important role of MD-2 in the CD14-independent LPS-mediated cascade of neutrophil influx; (2) the relative importance of bone marrow– and non–bone marrow cell–derived MD-2 in LPS-induced inflammation; and (3) the essential role of MD-2–dependent and MD-2–independent (TLR5) signaling in E. coli–induced neutrophil accumulation and pulmonary host defense