Michael Longaker, Postdoctoral Faculty Sponsor
Mesenchymal stem cells (MSC) have been repeatedly shown to be a valuable source for cell-based therapy in regenerative medicine, including bony tissue repair. However, engraftment at the injury site is poor. Recently, it has been suggested that MSCs and other cells act via a paracrine signaling mechanism. Exosomes are nanostructures that have been implicated in this process. They carry DNA, RNA, proteins and lipids and play an important role in cell-to-cell communication directly modulating their target cell at a transcriptional level. In a bone microenvironment, they have been shown to increase osteogenesis and osteogenic differentiation in vivo and in vitro. In the following review, we will discuss the most advanced and significant knowledge of biological functions of exosomes in bone regeneration and their clinical applications in osseous diseases.
View details for DOI 10.1089/ten.TEB.2020.0246
View details for PubMedID 33297857
Fibroblast heterogeneity has been shown within the unwounded mouse dorsal dermis, with fibroblast subpopulations being identified according to anatomical location and embryonic lineage. Using lineage tracing, we demonstrate that paired related homeobox 1 (Prrx1)-expressing fibroblasts are responsible for acute and chronic fibroses in the ventral dermis. Single-cell transcriptomics further corroborated the inherent fibrotic characteristics of Prrx1 fibroblasts during wound repair. In summary, we identify and characterize a fibroblast subpopulation in the mouse ventral dermis with intrinsic scar-forming potential.
View details for DOI 10.1016/j.celrep.2020.108356
View details for PubMedID 33176144
View details for Web of Science ID 000582792300410
View details for Web of Science ID 000582792300070
View details for Web of Science ID 000548418300052
View details for Web of Science ID 000560022400018
View details for Web of Science ID 000548418300069
On 11th March 2020, the spread of the SARS-CoV-2 virus was declared a pandemic by the World Health Organisation (WHO). Approximately 5.6 million have now been infected and over 350,000 have died. This global public health crisis has since cascaded into a series of challenges for leaders around the world, threatening both the health and economy of populations. This paper attempts to compartmentalise leadership aspects, allowing a closer examination of reports and the analysis of outcomes. The authors are thus enabled to formulate a number of evidence-based recommendations on the de-escalation of restrictions.
View details for DOI 10.1016/j.ijsu.2020.07.026
View details for PubMedID 32687873
Tissue fibrosis is the deposition of excessive extracellular matrix and can occur as part of the body's natural wound healing process upon injury, or as a consequence of diseases such as systemic sclerosis. Skin fibrosis contributes to significant morbidity due to the prevalence of injuries resulting from trauma and burn. Fibroblasts, the principal cells of the dermis, synthesize extracellular matrix to maintain the skin during homeostasis and also play a pivotal role in all stages of wound healing. Although it was previously believed that fibroblasts are homogeneous and mostly quiescent cells, it has become increasingly recognized that numerous fibroblast subtypes with unique functions and morphologies exist. This Review provides an overview of fibroblast heterogeneity in the mammalian dermis. We explain how fibroblast identity relates to their developmental origin, anatomical site and precise location within the skin tissue architecture in both human and mouse dermis. We discuss current evidence for the varied functionality of fibroblasts within the dermis and the relationships between fibroblast subtypes, and explain the current understanding of how fibroblast subpopulations may be controlled through transcriptional regulatory networks and paracrine communications. We consider how fibroblast heterogeneity can influence wound healing and fibrosis, and how insight into fibroblast heterogeneity could lead to novel therapeutic developments and targets for skin fibrosis. Finally, we contemplate how future studies should be shaped to implement knowledge of fibroblast heterogeneity into clinical practice in order to lessen the burden of skin fibrosis.
View details for DOI 10.1242/dmm.044164
View details for PubMedID 32541065
The Coronavirus (COVID-19) pandemic has resulted in over 2.3 million confirmed cases and over 160,000 deaths. The impact of COVID-19 on surgical practice is widespread ranging from workforce and staffing issues, procedural prioritisation, viral transmission risk intraoperatively, changes to perioperative practice and ways of working alongside the impact on surgical education and training. Whilst there has been a growing literature base describing the early clinical course of COVID-19 and on aspects of critical care related to treating these patients, there has been a dearth of evidence on how this pandemic will affect surgical practice. This paper seeks to review the current evidence and offers recommendations for changes to surgical practice to minimise the effect of the COVID-19 pandemic.
View details for DOI 10.1016/j.ijsu.2020.05.022
View details for PubMedID 32407799
View details for PubMedCentralID PMC7214340
The Coronavirus (COVID-19) Pandemic represents a once in a century challenge to human healthcare with 2.4 million cases and 165,000 deaths thus far. Surgical practice has been significantly impacted with all specialties writing guidelines for how to manage during this crisis. All specialties have had to triage the urgency of their daily surgical procedures and consider non-surgical management options where possible. The Pandemic has had ramifications for ways of working, surgical techniques, open vs minimally invasive, theatre workflow, patient and staff safety, training and education. With guidelines specific to each specialty being implemented and followed, surgeons should be able to continue to provide safe and effective care to their patients during the COVID-19 pandemic. In this comprehensive and up to date review we assess changes to working practices through the lens of each surgical specialty.
View details for DOI 10.1016/j.ijsu.2020.05.002
View details for PubMedID 32413502
View details for PubMedCentralID PMC7217115
The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs offers a paradigm shift in plastic and reconstructive surgery. The use of either embryonic stem cells (ESC) or induced pluripotent stem cells (iPSC) in clinical situations is limited because of regulations and ethical considerations even though these cells are theoretically highly beneficial. Adult mesenchymal stem cells appear to be an ideal stem cell population for practical regenerative medicine. Among these cells, adipose-derived stem cells (ADSC) have the potential to differentiate the mesenchymal, ectodermal and endodermal lineages and are easy to harvest. Additionally, adipose tissue yields a high number of ADSC per volume of tissue. Based on this background knowledge, the purpose of this review is to summarise and describe the proliferation and differentiation capacities of ADSC together with current preclinical data regarding the use of ADSC as regenerative tools in plastic and reconstructive surgery.
View details for DOI 10.1111/iwj.12569
View details for Web of Science ID 000392919100017
View details for PubMedID 26833722
Latest information on COVID-19