Adipose-derived stem cell collection and characterization in bottlenose dolphins (Tursiops truncatus)

Capture and Release of Cancer Cells Through Smart Bioelectronics

Noninvasive collection of target cells such as circulating tumor cells (CTCs) is crucial for biology and medicine research. Conventional methods of cell collection are often complex, requiring either size-dependent sorting or invasive enzymatic reactions. Here, we show the development of a functional polymer film, which combines the thermoresponsive poly(N-isopropylacrylamide) and the conducting poly(3,4-ethylenedioxythiopene)/poly(styrene sulfonate), and its use for the capture and release of CTCs. When coated onto microfabricated gold electrodes, the proposed polymer films are capable of noninvasively capturing and controllably releasing cells while, at the same time, monitoring these processes with conventional electrical measurements.

Cadaveric Stem Cells: Their Research Potential and Limitations

In the era of growing interest in stem cells, the availability of donors for transplantation has become a problem. The isolation of embryonic and fetal cells raises ethical controversies, and the number of adult donors is deficient. Stem cells isolated from deceased donors, known as cadaveric stem cells (CaSCs), may alleviate this problem. So far, it was possible to isolate from deceased donors mesenchymal stem cells (MSCs), adipose delivered stem cells (ADSCs), neural stem cells (NSCs), retinal progenitor cells (RPCs), induced pluripotent stem cells (iPSCs), and hematopoietic stem cells (HSCs). Recent studies have shown that it is possible to collect and use CaSCs from cadavers, even these with an extended postmortem interval (PMI) provided proper storage conditions (like cadaver heparinization or liquid nitrogen storage) are maintained. The presented review summarizes the latest research on CaSCs and their current therapeutic applications. It describes the developments in thanatotranscriptome and scaffolding for cadaver cells, summarizes their potential applications in regenerative medicine, and lists their limitations, such as donor’s unknown medical condition in criminal cases, limited differentiation potential, higher risk of carcinogenesis, or changing DNA quality. Finally, the review underlines the need to develop procedures determining the safe CaSCs harvesting and use.

An electroactive and thermo-responsive material for the capture and release of cells

Non-invasive collection of target cells is crucial for research in biology and medicine. In this work, we combine a thermo-responsive material, poly(N-isopropylacrylamide), with an electroactive material, poly(3,4-ethylene-dioxythiopene):poly(styrene sulfonate), to generate a smart and conductive copolymer for the label-free and non-invasive detection of the capture and release of cells on gold electrodes by electrochemical impedance spectroscopy. The copolymer is functionalized with fibronectin to capture tumor cells, and undergoes a conformational change in response to temperature, causing the release of cells. Simultaneously, the copolymer acts as a sensor, monitoring the capture and release of cancer cells by electrochemical impedance spectroscopy. This platform has the potential to play a role in top-notch label-free electrical monitoring of human cells in clinical settings.

Functional Studies with Primary Cells Provide a System for Genome-to-Phenome Investigations in Marine Mammals

Marine mammals exhibit some of the most dramatic physiological adaptations in their clade and offer unparalleled insights into the mechanisms driving convergent evolution on relatively short time scales. Some of these adaptations, such as extreme tolerance to hypoxia and prolonged food deprivation, are uncommon among most terrestrial mammals and challenge established metabolic principles of supply and demand balance. Non-targeted omics studies are starting to uncover the genetic foundations of such adaptations, but tools for testing functional significance in these animals are currently lacking. Cellular modeling with primary cells represents a powerful approach for elucidating the molecular etiology of physiological adaptation, a critical step in accelerating genome-to-phenome studies in organisms in which transgenesis is impossible (e.g., large-bodied, long-lived, fully aquatic, federally protected species). Gene perturbation studies in primary cells can directly evaluate whether specific mutations, gene loss, or duplication confer functional advantages such as hypoxia or stress tolerance in marine mammals. Here, we summarize how genetic and pharmacological manipulation approaches in primary cells have advanced mechanistic investigations in other non-traditional mammalian species, and highlight the need for such investigations in marine mammals. We also provide key considerations for isolating, culturing, and conducting experiments with marine mammal cells under conditions that mimic in vivo states. We propose that primary cell culture is a critical tool for conducting functional mechanistic studies (e.g., gene knockdown, over-expression, or editing) that can provide the missing link between genome- and organismal-level understanding of physiological adaptations in marine mammals.

Development and Characterization of an Antimicrobial Polydopamine Coating for Conservation of Humpback Whales

Migration patterns of humpback whales have been monitored using 316L stainless steel (SS) satellite telemetry tags. The potential for tissue infection and necrosis is increased if the bacteria, naturally a part of the diverse microbiome on the skin of humpback whales, can adhere to and colonize the surface of the tags. Polydopamine (pDA) has the potential to prevent the adhesion of one of the most prevalent bacterial strains on the surface of the skin of cetaceans (Psychrobacter) through the release of hydrogen peroxide. The release of hydrogen peroxide from the pDA coatings (40-100 μM) has the ability to induce a bacteriostatic response in E. coli, a commonly used bacteria strain in antimicrobial studies and potentially P. cryohalolentis, a common humpback associated bacteria. The H₂O₂ dose required to induce bacteriostatic conditions in E. coli is approximately 60 μM and in P. cryohalolentis is 100 μM. Bacterial adhesion on the surface of pDA coated SS coupons was measured first using E. coli. The coating successfully prevented adhesion of E. coli on the surface of SS coupons under certain conditions (60% reduction, p < 0.05) but the same was not seen with P. cryohalolentis. When coating conditions were altered (an increase in pH and temperature) the adhesion of P. cryohalolentis was reduced (80% reduction, p < 0.001). Overall, the pDA coatings have the capacity to generate varying amounts of hydrogen peroxide by altering the coating conditions and have the ability to reduce bacterial adhesion on the surface of satellite telemetry tags, and therefore the potential to increase tag functional service lifetime.

Current Status of Canine Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Veterinary Medicine

Stem cell therapy has prompted the expansion of veterinary medicine both experimentally and clinically, with the potential to contribute to contemporary treatment strategies for various diseases and conditions for which limited or no therapeutic options are presently available. Although the application of various types of stem cells, such as bone marrow-derived mesenchymal stem cells (BM-MSCs), adipose tissue-derived mesenchymal stem cells (AT-MSCs), and umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), has promising potential to improve the health of different species, it is crucial that the benefits and drawbacks are completely evaluated before use. Umbilical cord blood (UCB) is a rich source of stem cells; nonetheless, isolation of mesenchymal stem cells (MSCs) from UCB presents technical challenges. Although MSCs have been isolated from UCB of diverse species such as human, equine, sheep, goat, and canine, there are inherent limitations of using UCB from these species for the expansion of MSCs. In this review, we investigated canine UCB (cUCB) and compared it with UCB from other species by reviewing recent articles published from February 2003 to June 2017 to gain an understanding of the limitations of cUCB in the acquisition of MSCs and to determine other suitable sources for the isolation of MSCs from canine. Our review indicates that cUCB is not an ideal source of MSCs because of insufficient volume and ethical issues. However, canine reproductive organs discarded during neutering may help broaden our understanding of effective isolation of MSCs. We recommend exploring canine reproductive and adipose tissue rather than UCB to fulfill the current need in veterinary medicine for the well-designed and ethically approved source of MSCs.

Plasma Rich in Growth Factors Induces Cell Proliferation, Migration, Differentiation, and Cell Survival of Adipose-Derived Stem Cells

Adipose-derived stem cells (ASCs) are a promising therapeutic alternative for tissue repair in various clinical applications. However, restrictive cell survival, differential tissue integration, and undirected cell differentiation after transplantation in a hostile microenvironment are complications that require refinement. Plasma rich in growth factors (PRGF) from platelet-rich plasma favors human and canine ASC survival, proliferation, and delaying human ASC senescence and autophagocytosis in comparison with serum-containing cultures. In addition, canine and human-derived ASCs efficiently differentiate into osteocytes, adipocytes, or chondrocytes in the presence of PRGF. PRGF treatment induces phosphorylation of AKT preventing ASC death induced by lethal concentrations of hydrogen peroxide. Indeed, AKT inhibition abolished the PRGF apoptosis prevention in ASC exposed to 100 μM of hydrogen peroxide. Here, we show that canine ASCs respond to PRGF stimulus similarly to the human cells regarding cell survival and differentiation postulating the use of dogs as a suitable translational model. Overall, PRGF would be employed as a serum substitute for mesenchymal stem cell amplification to improve cell differentiation and as a preconditioning agent to prevent oxidative cell death.

Human Suprapatellar Fat Pad-Derived Mesenchymal Stem Cells Induce Chondrogenesis and Cartilage Repair in a Model of Severe Osteoarthritis

Cartilage degeneration is associated with degenerative bone and joint processes in severe osteoarthritis (OA). Spontaneous cartilage regeneration is extremely limited. Often the treatment consists of a partial or complete joint implant. Adipose-derived stem cell (ASC) transplantation has been shown to restore degenerated cartilage; however, regenerative differences of ASC would depend on the source of adipose tissue. The infra- and suprapatellar fat pads surrounding the knee offer a potential autologous source of ASC for patients after complete joint substitution. When infrapatellar- and suprapatellar-derived stromal vascular fractions (SVF) were compared, a significantly higher CD105 (+) population was found in the suprapatellar fat. In addition, the suprapatellar SVF exhibited increased numbers of colony formation units and a higher population doubling in culture compared to the infrapatellar fraction. Both the suprapatellar- and infrapatellar-derived ASC were differentiated in vitro into mature adipocytes, osteocytes, and chondrocytes. However, the suprapatellar-derived ASC showed higher osteogenic and chondrogenic efficiency. Suprapatellar-derived ASC transplantation in a severe OA mouse model significantly diminished the OA-associated knee inflammation and cartilage degenerative grade, significantly increasing the production of glycosaminoglycan and inducing endogenous chondrogenesis in comparison with the control group. Overall, suprapatellar-derived ASC offer a potential autologous regenerative treatment for patients with multiple degenerative OA.

Clinical management of Candida albicans keratomycosis in a bottlenose dolphin (Tursiops truncatus)

OBJECTIVE

Corneal ulceration secondary to trauma commonly affects marine mammals, often with opportunistic secondary bacterial or fungal infections. This report characterizes the combined use of auriculopalpebral and ophthalmic nerve blocks, adipose-derived stem cells, and subconjunctival injections for successful treatment of corneal trauma and infection in dolphins.

ANIMAL STUDIED

An 11-year-old, female bottlenose dolphin (Tursiops truncatus) presented with bilateral diffuse corneal opacities, which progressed to keratomycosis caused by Candida albicans.

PROCEDURE

Aggressive medical management was employed, including the use of subconjunctival injections of adipose-derived stem cells, plasma, topical and oral antifungals and antibiotics, and anti-inflammatory and pain medications. Anesthetic block of the auriculopalpebral and ophthalmic nerves was employed to evaluate the corneas.

CONCLUSION

Subconjunctival injections were employed over 52 days, followed by topical drops for 5 months. At last evaluation, there was no evidence of blepharospasm bilaterally. Only a faint superficial gray corneal opacity remained OS. A temporal paraxial corneal opacity was present OD, with receding inactive vascularization and a small amount of melanosis temporally.

Adipose-derived stem cells seeded on polyglycolic acid for the treatment of stress urinary incontinence

PURPOSE

To evaluate the effect and possible mechanism of suburethral tissue-engineered sling in an animal model of stress urinary incontinence (SUI).

METHODS

Adipose-derived stem cells (ADSCs) were obtained from the adipose tissues of rats. The differentiation potential, proliferation, and viability of rat ADSCs were evaluated after infecting these cells with a lentiviral vector-encoding green fluorescent protein (GFP). Next, GFP transfected ADSCs were seeded on polyglycolic acid (PGA) fibers to construct the tissue-engineered sling with the induction of 5-azacytidine (5-Aza). Afterward, the tissue-engineered slings were transplanted into a rat model of SUI that was established by vaginal balloon dilatation method and bilateral ovariectomy. Histology and the leak point pressure measurements were performed at 2 months after tissue-engineered sling implantation.

RESULTS

The ADSCs were found to be efficiently transfected with GFP, without any effects on proliferation, cell cycle and multi-differentiation potential. After been seeded on PGA fibers, ADSCs formed tissue-engineered slings in 4 weeks of induction culture. Two months after implantation, the mean leak point pressure (LPP) was significantly increased in sling-treated rats compared with the balloon-injured ovariectomized rats. Immunofluorescence assay showed that some of the GFP expressing cells stained positive for muscle-specific markers.

CONCLUSIONS

The newly suburethral tissue-engineered sling restores LPP in the rat model of SUI, which could be an effective treatment in future SUI therapy.

Platelet-rich plasma and adipose-derived mesenchymal stem cells for regenerative medicine-associated treatments in bottlenose dolphins (Tursiops truncatus)

Dolphins exhibit an extraordinary capacity to heal deep soft tissue injuries. Nevertheless, accelerated wound healing in wild or captive dolphins would minimize infection and other side effects associated with open wounds in marine animals. Here, we propose the use of a biological-based therapy for wound healing in dolphins by the application of platelet-rich plasma (PRP). Blood samples were collected from 9 different dolphins and a specific and simple protocol which concentrates platelets greater than two times that of whole blood was developed. As opposed to a commonly employed human protocol for PRP preparation, a single centrifugation for 3 minutes at 900 rpm resulted in the best condition for the concentration of dolphin platelets. By FACS analysis, dolphin platelets showed reactivity to platelet cell-surface marker CD41. Analysis by electron microscopy revealed that dolphin platelets were larger in size than human platelets. These findings may explain the need to reduce the duration and speed of centrifugation of whole blood from dolphins to obtain a 2-fold increase and maintain proper morphology of the platelets. For the first time, levels of several growth factors from activated dolphin platelets were quantified. Compared to humans, concentrations of PDGF-BB were not different, while TGFβ and VEGF-A were significantly lower in dolphins. Additionally, adipose tissue was obtained from cadaveric dolphins found along the Spanish Mediterranean coast, and adipose-derived mesenchymal stem cells (ASCs) were successfully isolated, amplified, and characterized. When dolphin ASCs were treated with 2.5 or 5% dolphin PRP they exhibited significant increased proliferation and improved phagocytotic activity, indicating that in culture, PRP may improve the regenerative capacity of ASCs. Taken together, we show an effective and well-defined protocol for efficient PRP isolation. This protocol alone or in combination with ASCs, may constitute the basis of a biological treatment for wound-healing and tissue regeneration in dolphins.

Induced pluripotent stem cell technology and aquatic animal species

Aquatic animal species are the overall leaders in the scientific investigation of tough but important global health issues, including environmental toxicants and climate change. Historically, aquatic animal species also stand at the forefront of experimental biology, embryology and stem cell research. Over the past decade, intensive and high-powered investigations principally involving mouse and human cells have brought the generation and study of induced pluripotent stem cells (iPSCs) to a level that facilitates widespread use in a spectrum of species. A review of key features of these investigations is presented here as a primer for the use of iPSC technology to enhance ongoing aquatic animal species studies. iPSC and other cutting edge technologies create the potential to study individuals from "the wild" closer to the level of investigation applied to sophisticated inbred mouse models. A wide variety of surveys and hypothesis-driven investigations can be envisioned using this new capability, including comparisons of organism-specific development and exposure response and the testing of fundamental dogmas established using inbred mice. However, with these new capabilities, also come new criteria for rigorous baseline assessments and testing. Both the methods for inducing pluripotency and the source material can negatively impact iPSC quality and bourgeoning applications. Therefore, more rigorous strategies not required for inbred mouse models will have to be implemented to approach global health issues using individuals from "the wild" for aquatic animal species.

Stem cell therapy in veterinary dermatology

BACKGROUND

Adult stem cells come from many sources and have the capacity to differentiate into many cell types, including those of the skin. The most commonly studied stem cells are those termed mesenchymal stem cells (MSCs), which are easily isolated from bone marrow and adipose tissue. Mesenchymal stem cells are known to produce a wide array of cytokines that modulate the regeneration process. The ease of collection, propagation and use of these MSCs in therapy of traumatic, ischaemic and immune-mediated skin conditions is emerging.

APPROACH AND EVIDENCE

In traumatic and ischaemic skin damage, MSCs are used in tissue-engineered skin and by direct injection into damaged tissue. For immune-mediated diseases, systemic administration of stem cells can modulate the immune system. The earliest clinical work has been with autologous stem cell sources, such as adipose tissue and bone marrow. In immune-mediated diseases, the MSCs are used to downregulate production of inflammatory cytokines and to block T-cell activation. Cells are generally given intravenously. Multiple sclerosis, rheumatoid arthritis and lupus have been successfully treated in human clinical trials. Mesenchymal stem cells can also stimulate resident local cells, such as keratinocytes and progenitor cells, to proliferate, migrate and repair skin injury and disease.

LOOKING AHEAD

The discovery of the MSC in adipose tissue has spawned a global effort to utilize these cells in therapy of a wide range of diseases of the skin. Reconstructive surgery, scar blocking and resolution and skin regeneration have all been shown to be possible in human and animal studies.