Hypoxic conditions promote a proliferative, poorly differentiated phenotype in COPD lung tissue progenitor cells in vitro

PURPOSE: Chronic obstructive pulmonary disease (COPD) patients experience hypoxemia and lung tissue hypoxia, causing vasoconstriction, and at its most severe Cor pulmonale. However, minimal attention has been given to the effects of hypoxia at the cellular level. We hypothesize that a persistent progenitor cell population undergoes an aberrant differentiation process, influenced by changes in oxygen. METHODS: Distal lung progenitor cells from two emphysematous donors were cultured in 21% and 2% oxygen. Proliferation was determined on collagen-coated plastic and in 3T3-J2 co-culture. Epithelial (E-cadherin, pan-cytokeratin) and progenitor (TP63, cytokeratin 5) marker expressions were examined. Cells were differentiated at air-liquid interface, and ciliated, mucus-producing, and club cell populations identified by immunofluorescence. MUC5AC, MUC5B, CC10, and TP63 expression were determined using qRT-PCR, mucin5AC, and mucin5B protein levels by ELISA, and secreted mucin by periodic acid biotin hydrazide assay. RESULTS: Cells were positive for epithelial and progenitor markers at isolation and passage 5. Passage 5 cells in hypoxia increased the proportion of TP63 by 10% from 51.6?±?1.2% to 62.6?±?2.3% (p?=?0.01). Proliferative capacity was greater on 3T3J2 cells and in 2% oxygen, supporting the emergence of a proliferation unrestricted population with limited differentiation capacity. Differentiation resulted in ßIV tubulin positive-ciliated cells, mucin5AC, mucin5B, and CC10 positive secretory cells. Epithelial barrier formation was reduced (p?=?0.0001) in hypoxia-expanded cells. qRT-PCR showed higher mucin expression in 2% cells, significantly so with MUC5B (p?=?0.05). Although overall mucin5AC and mucin5B content was greater in 21% cells, normalization of secreted mucin to DNA showed a trend for increased mucin by low oxygen cells. CONCLUSIONS: These results demonstrate that hypoxia promotes a proliferative phenotype while affecting subsequent progenitor cell differentiation capacity. Furthermore, the retained differentiation potential becomes skewed to a more secretory phenotype, demonstrating that hypoxia may be contributing to disease symptoms and severity in COPD patients

Injectable hydrogels : An emerging therapeutic strategy for cartilage regeneration

Funding Information: The authors acknowledge the funding support from the North Staffordshire Medical Institute (NSMI Research Awards 2021). Arjan Atwal gratefully thanks Faculty of Medicine and Health Sciences , Keele University , for funding his PhD studentship.Peer reviewedPublisher PD

Tuning the properties of all natural polymeric scaffolds for tendon repair with cellulose microfibers

Funding Information: This paper is a part of dissemination activities of the project P4FIT. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Maria Skłodowska-Curie Grant Agreement N° 955685 .Peer reviewe

Hypoxic conditions promote a proliferative, poorly differentiated phenotype in COPD lung tissue progenitor cells in vitro

Acknowledgements The authors would like to acknowledge the support of the UHNM theatre staff, Dr. Sana Iftikhar and Dr. Daniel Gey van Pittius for their assistance in acquiring participant lung tissue. Funding Information: This work was supported by funding from the North Staffordshire Medical Institute 50th Anniversary Award and The Royal Society-Newton Mobility Grant. The authors would like to acknowledge the support of the UHNM theatre staff, Dr. Sana Iftikhar and Dr. Daniel Gey van Pittius for their assistance in acquiring participant lung tissue.Peer reviewedPublisher PD

Ectopic Telomerase Expression Fails to Maintain Chondrogenic Capacity in Three-Dimensional Cultures of Clinically Relevant Cell Types.

The poor healing capacity of cartilage and lack of effective treatment for associated disease and trauma makes it a strong candidate for a regenerative medicine approach. Potential therapies tested to date, although effective, have met with a number of intrinsic difficulties possibly related to limited autologous chondrocyte cell yield and quality of cartilage produced. A potential mechanism to bypass limited cell yields and improve quality of differentiation is to immortalize relevant cell types through the ectopic expression of telomerase. Pellet cultures of human chondrocytes (OK3), bone marrow mesenchymal stem cells (BMA13), and embryonic stem cell (H1 line)-derived cells (1C6) and their human telomerase reverse transcriptase (hTERT) transduced counterparts were maintained for 20 days in standard maintenance medium (MM) or transforming growth factor-ß3-supplemented prochondrogenic medium (PChM). Pellets were assessed for volume and density by microcomputed tomography. Quantitative gene expression (COL1A2, COL2A1, COL3A1, COL6A3, COL10A1, ACAN, COMP, SOX9); sulfated glycosaminoglycans (sGAGs), and DNA quantification were performed. Histology and immunohistochemistry were used to determine matrix constituent distribution. Pellet culture in PChM resulted in significantly larger pellets with an overall increased density when compared with MM culture. Gene expression analysis revealed similarities in expression patterns between telomerase-transduced and parental cells in both MM and PChM. Of the three parental cell types examined OK3 and BMA13 produced similar amounts of pellet-associated sGAG in PChM (4.62?±?1.20 and 4.91?±?1.37?µg, respectively) with lower amounts in 1C6 (2.89?±?0.52?µg), corresponding to 3.1, 2.3, and 1.6-fold increases from day 0. In comparison, telomerase-transduced cells all had much lower sGAG with OK3H at 2.74?±?0.11?µg, BMA13H 1.29?±?0.34?µg, and 1C6H 0.52?±?0.01?µg corresponding to 1.2, 0.87, and 0.34-fold changes compared with day 0. Histology of day 20 pellets displayed reduced staining overall for collagens and sGAG in telomerase-transduced cells, most notably with alterations in aggrecan and collagen VI; all cells stained positively for collagen II. We conclude that while telomerase transduction may be an effective technique to extend cellular proliferative capacity, it is not sufficient in isolation to sustain a naive chondrogenic phenotype across multiple cell types

Endotenon-Derived Type II Tendon Stem Cells Have Enhanced Proliferative and Tenogenic Potential

Funding This project received funding from the European Union’s Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie grant agreement, No. 955685. This research also received funding support from the Engineering and Physical Sciences Research Council (EPSRC) Centre for Doctoral Training in Regenerative Medicine (EP/L015072/1).Peer reviewedPublisher PD

Hypoxia-Modified Cancer Cell Metabolism

While oxygen is critical to the continued existence of complex organisms, extreme levels of oxygen within a system, known as hypoxia (low levels of oxygen) and hyperoxia (excessive levels of oxygen), potentially promote stress within a defined biological environment. The consequences of tissue hypoxia, a result of a defective oxygen supply, vary in response to the gravity, extent and environment of the malfunction. Persistent pathological hypoxia is incompatible with normal biological functions, and as a result, multicellular organisms have been compelled to develop both organism-wide and cellular-level hypoxia solutions. Both direct, including oxidative phosphorylation down-regulation and inhibition of fatty-acid desaturation, and indirect processes, including altered hypoxia-sensitive transcription factor expression, facilitate the metabolic modifications that occur in response to hypoxia. Due to the dysfunctional vasculature associated with large areas of some cancers, sections of these tumors continue to develop in hypoxic environments. Crucial to drug development, a robust understanding of the significance of these metabolism changes will facilitate our understanding of cancer cell survival. This review defines our current knowledge base of several of the hypoxia-instigated modifications in cancer cell metabolism and exemplifies the correlation between metabolic change and its support of the hypoxic-adapted malignancy

Understanding cognition in older patients with cancer

Cancer and neurocognitive disorders, such as dementia and delirium, are common and serious diseases in the elderly that are accompanied by high degree of morbidity and mortality. Furthermore, evidence supports the under-diagnosis of both dementia and delirium in older adults. Complex questions exist regarding the interaction of dementia and delirium with cancer, beginning with guidelines on how best measure disease severity, the optimal screening test for either disorder, the appropriate level of intervention in the setting of abnormal findings, and strategies aimed at preventing the development or progression of either process. Ethical concerns emerge in the research setting, pertaining to the detection of cognitive dysfunction in participants, validity of consent, disclosure of abnormal results if screening is pursued, and recommended level of intervention by investigators. Furthermore, understanding the ways in which comorbid cognitive dysfunction and cancer impact both cancer and non-cancer-related outcomes is essential in guiding treatment decisions. In the following article, we will discuss what is presently known of the interactions of pre-existing cognitive impairment and delirium with cancer. We will also discuss identified deficits in our knowledge base, and propose ways in which innovative research may address these gaps

IL1RL1 Gene Variants and Nasopharyngeal IL1RL-a Levels Are Associated with Severe RSV Bronchiolitis: A Multicenter Cohort Study

Targets for intervention are required for respiratory syncytial virus (RSV) bronchiolitis, a common disease during infancy for which no effective treatment exists. Clinical and genetic studies indicate that IL1RL1 plays an important role in the development and exacerbations of asthma. Human IL1RL1 encodes three isoforms, including soluble IL1RL1-a, that can influence IL33 signalling by modifying inflammatory responses to epithelial damage. We hypothesized that IL1RL1 gene variants and soluble IL1RL1-a are associated with severe RSV bronchiolitis.We studied the association between RSV and 3 selected IL1RL1 single-nucleotide polymorphisms rs1921622, rs11685480 or rs1420101 in 81 ventilated and 384 non-ventilated children under 1 year of age hospitalized with primary RSV bronchiolitis in comparison to 930 healthy controls. Severe RSV infection was defined by need for mechanical ventilation. Furthermore, we examined soluble IL1RL1-a concentration in nasopharyngeal aspirates from children hospitalized with primary RSV bronchiolitis. An association between SNP rs1921622 and disease severity was found at the allele and genotype level (p = 0.011 and p = 0.040, respectively). In hospitalized non-ventilated patients, RSV bronchiolitis was not associated with IL1RL1 genotypes. Median concentrations of soluble IL1RL1-a in nasopharyngeal aspirates were >20-fold higher in ventilated infants when compared to non-ventilated infants with RSV (median [and quartiles] 9,357 [936-15,528] pg/ml vs. 405 [112-1,193] pg/ml respectively; p<0.001).We found a genetic link between rs1921622 IL1RL1 polymorphism and disease severity in RSV bronchiolitis. The potential biological role of IL1RL1 in the pathogenesis of severe RSV bronchiolitis was further supported by high local concentrations of IL1RL1 in children with most severe disease. We speculate that IL1RL1a modifies epithelial damage mediated inflammatory responses during RSV bronchiolitis and thus may serve as a novel target for intervention to control disease severity