Stem Cells, Cell Therapies, and Bioengineering in Lung Biology and Disease 2021

The 9th biennial conference titled “Stem Cells, Cell Therapies, and Bioengineering in Lung Biology and Diseases” was hosted virtually, due to the ongoing COVID-19 pandemic, in collaboration with the University of Vermont Larner College of Medicine, the National Heart, Lung, and Blood Institute, the Alpha-1 Foundation, the Cystic Fibrosis Foundation, and the International Society for Cell & Gene Therapy. The event was held from July 12th through 15th, 2021 with a pre-conference workshop held on July 9th. As in previous years, the objectives remained to review and discuss the status of active research areas involving stem cells (SCs), cellular therapeutics, and bioengineering as they relate to the human lung. Topics included 1) technological advancements in the in situ analysis of lung tissues, 2) new insights into stem cell signaling and plasticity in lung remodeling and regeneration, 3) the impact of extracellular matrix in stem cell regulation and airway engineering in lung regeneration, 4) differentiating and delivering stem cell therapeutics to the lung, 5) regeneration in response to viral infection, and 6) ethical development of cell-based treatments for lung diseases. This selection of topics represents some of the most dynamic and current research areas in lung biology

Development of high density systems for the production of recombinant proteins by insect cells

The ever-increasing demand for therapeutic proteins with correct post-translational modifications has led to the development of various expression Systems that make use of animal cells. Among these Systems, the Baculovirus Expression Vector System (BEVS) is one of the most popular. It uses lepidopteran cells, which are infected with a recombinant insect virus, the baculovirus, coding for the protein of interest. Large amounts of recombinant proteins can be expressed under the control of the powerful polyhedrin promoter. The successful scale-up of the BEVS nécessitâtes fast-growing cell fines, low-cost culture media (preferably, serum-free) and maintenance of the spécifie protein production at high-density infections.Doctorat en sciences appliquées (FSA 3)--UCL, 200

Ethical issues and public communication in the development of cell-based treatments for COVID-19: Lessons from the pandemic.

The significant morbidity and mortality of coronavirus disease 19 (COVID-19) prompted a global race to develop new therapies. These include interventions using cell- or cell-derived products, several of which are being tested in well-designed, properly controlled clinical trials. Yet, the search for cell-based COVID-19 treatments has also been fraught with hyperbolic claims; flouting of crucial regulatory, scientific, and ethical norms; and distorted communication of research findings. In this paper, we critically examine ethical issues and public communication challenges related to the development of cell-based therapeutics for COVID-19. Drawing on the lessons learned from this ongoing process, we argue against the rushed development of cell-based interventions. We conclude by outlining ways to improve the ethical conduct of cell-based clinical investigations and public communication of therapeutic claims

Growth on microcarriers and nutritional needs of high density insect cell cultures

The insect cell/baculovirus (ICB) system has become popular both for the production of recombinant proteins and biopesticides. The development of serum-free media, advances in baculovirus vector construction and the relative simplicity of insect cell culture make the ICB quite powerful and versatile for recombinant protein expression. We report here experimental results on the growth of insect cells in bioreactor. The evaluation of insect cell growth on Fibra-Cel® microcarriers in suspension is also presented

Translating Basic Research into Safe and Effective Cell-based Treatments for Respiratory Diseases

Respiratory diseases, such as chronic obstructive pulmonary disease and pulmonary fibrosis, result in severely impaired quality of life and impose significant burdens on healthcare systems worldwide. Current disease management involves pharmacologic interventions, oxygen administration, reduction of infections, and lung transplantation in advanced disease stages. An increasing understanding of mechanisms of respiratory epithelial and pulmonary vascular endothelial maintenance and repair and the underlying stem/progenitor cell populations, including but not limited to airway basal cells and type II alveolar epithelial cells, has opened the possibility of cell replacement-based regenerative approaches for treatment of lung diseases. Further potential for personalized therapies, including in vitro drug screening, has been underscored by the recent derivation of various lung epithelial, endothelial, and immune cell types from human induced pluripotent stem cells. In parallel, immunomodulatory treatments using allogeneic or autologous mesenchymal stromal cells have shown a good safety profile in clinical investigations for acute inflammatory conditions such as acute respiratory distress syndrome and septic shock. As yet, no cell-based therapy has been shown to be both safe and effective for any lung disease. Despite the investigational status of cell-based interventions for lung diseases, businesses that market unproven, unlicensed and potentially harmful cell-based interventions for respiratory diseases have proliferated in the U.S. and worldwide. The current status of various cell-based regenerative approaches for lung disease as well as the effect of the regulatory environment on clinical translation of such approaches are presented and critically discussed in this review

Supernatant proteolytic activities of High-Five insect cells grown in serum-free culture

The proteolytic activity of High-Five insect cell culture supernatants was analysed using substrate gel electrophoresis (zymography). During growth in serum-free media, High-Five cells constitutively expressed and secreted proteases that were active on casein gel but not on gelatin or bovine serum albumin gels. Two main protease bands were visible at about 41-42 kDa and 32-33 kDa. By addition of various protease inhibitors in the incubation buffer, the proteases were identified as metalloproteases as complete and specific inhibition of the proteolytic activities was only obtained by 1,10-phenanthroline

Design of an Efficient Medium for Insect Cell Growth and Recombinant Protein Production

We report the development of a new serum-free medium based on the use of factorial experiments. At first, a variety of hydrolysates were screened using a fractional factorial approach with High-Five cells. From this experiment yeastolate ultrafiltrate was found to have, by far, the most important effect on cell growth. Furthermore, Primatone RL was found to remarkably prolong the stationary phase of Sf-9 and High-Five cell cultures. The optimal concentrations for yeastolate and Primatone were determined to be 0.6 and 0.5%, respectively, on the basis of a complete factorial experiment. This new medium, called YPR, supported good growth of both Sf-9 and High-Five cells in batch cultures, with maximal densities of 5.4 and 6.1 x 10(6) cells/ml, respectively. In addition, both cell lines achieved good growth in bioreactor batch culture and had a prolonged stationary phase of 3-4 d in YPR medium compared to Insect-XPRESS medium. The ability of the new medium to support recombinant protein expression was also tested by infecting Sf-9 or High-Five cells at high density (2 x 10(6) cells/ml) with a baculovirus expressing secreted placental alkaline phosphatase (SEAP). The maximum total SEAP concentration after 7 d was about 43 lU/ml (58 mg/L) and 28 lU/ml (39 mg/L) for High-Five and Sf-9 cells, respectively