RNA-seq strategy to study Mycobacterium ulcerans adaptation within our original mouse model of spontaneous healing.
Ontology highlight
ABSTRACT: Mycobacterium ulcerans is the causal agent of Buruli ulcer, a chronic infectious disease and the third most common mycobacterial disease worldwide. Without early treatment, M. ulcerans provokes massive skin ulcers, caused by the mycolactone toxin, its main virulence factor. However, spontaneous healing may occur in Buruli ulcer patients several months or years after the disease onset. We have shown, in an original mouse model, that bacterial load remains high and viable in spontaneously healed tissues, suggesting that M. ulcerans switches to low levels of mycolactone production, adapting its strategy to survive in such a hostile environment. We investigated the regulation of mycolactone production, by using an RNA-seq strategy to study bacterial adaptation within our original mouse model of spontaneous healing. Pathway analysis and characterization of the tissue environment showed that the bacillus adapted to its new environment by modifying its metabolic activity and switching nutrient sources. Thus, M. ulcerans ensures its survival in healing tissues by reducing its secondary metabolism, leading to an inhibition of mycolactone synthesis and changes in cell wall composition. These findings shed new light on mycolactone regulation and pave the way for new therapeutic strategies.
Project description:Diabetic foot ulcers (DFUs) are a devastating complication of diabetes. To better understand the molecular mechanisms and cell types implicated in DFU healing, we used NanoString’s GeoMx Digital Spatial profiling platform on DFU tissue sections and compared gene expression of areas within the same ulcer as well as between patients who in 12 weeks following surgery healed their DFU (Healers, N=2) vs those who did not (Non-Healers, N=2).
Project description:Marjolin's ulcer is a a rare and aggressive cutaneous malignancy that can arise on previously injured skin, established scars, and chronic non-healing wounds. It is most often found in burn scars, but it can also occur in other types of wounds, including venous stasis ulcers, pressure sores, and vaccination sites. The most common histological type of Marjolin’s ulcers is squamous cell carcinoma, however basal cell carcinomas, malignant melanomas, and sarcomas have also been reported. All parts of the body could potentially be affected yet the lower extremities are the anatomic sites most commonly involved. While SCCs commonly have a metastasis rate of 0.5 to 3.0 percent, those arising from burn scars metastasize at a rate in excess of 30 percent. The 5-year survival after a diagnosis of Marjolin’s ulcer was found to be 50 percent. The transformation to a malignancy can occur either chronically, over a period of more than 35 years, or occasionally within a year of the original injury. The exact mechanism of this transformation is not fully understood, but it is thought to be related to chronic keratinocyte dysfunction during the healing process of severe burn wounds. Surgical excision is the main treatment for Marjolin's ulcer and provides the best chance of survival. In a previous study, we investigated the bulk transcriptional changes that lead to Marjolin's ulcer by comparing global gene expression changes between squamous cells present in a squamous cell carcinoma versus those present within Marjolin's ulcer (MU) (Sinha et. al. JBCR 2017). This imparted novel insights into mechanisms underlying divergent clinical features of these cutaneous cancers. The goal of our current study is to characterize a new case of Marjolin's ulcer in a patient under our care by analyzing the cell types, their frequencies, and their individual transcriptional responses within a burn scar versus within Marjolin's ulcer. To achieve this, we conducted single-cell RNA sequencing on two excised tissues: 1. a sample from the center of the tumor (tumor core), and 2. another sample from the margin of tumor-free scar tissue.
Project description:Marjolin's ulcer is a a rare and aggressive cutaneous malignancy that can arise on previously injured skin, established scars, and chronic non-healing wounds. It is most often found in burn scars, but it can also occur in other types of wounds, including venous stasis ulcers, pressure sores, and vaccination sites. The most common histological type of Marjolin’s ulcers is squamous cell carcinoma, however basal cell carcinomas, malignant melanomas, and sarcomas have also been reported. All parts of the body could potentially be affected yet the lower extremities are the anatomic sites most commonly involved. While SCCs commonly have a metastasis rate of 0.5 to 3.0 percent, those arising from burn scars metastasize at a rate in excess of 30 percent. The 5-year survival after a diagnosis of Marjolin’s ulcer was found to be 50 percent. The transformation to a malignancy can occur either chronically, over a period of more than 35 years, or occasionally within a year of the original injury. The exact mechanism of this transformation is not fully understood, but it is thought to be related to chronic keratinocyte dysfunction during the healing process of severe burn wounds. Surgical excision is the main treatment for Marjolin's ulcer and provides the best chance of survival. In a previous study, we investigated the bulk transcriptional changes that lead to Marjolin's ulcer by comparing global gene expression changes between squamous cells present in a squamous cell carcinoma versus those present within Marjolin's ulcer (MU) (Sinha et. al. JBCR 2017). This imparted novel insights into mechanisms underlying divergent clinical features of these cutaneous cancers. The goal of our current study is to characterize a new case of Marjolin's ulcer in a patient under our care by analyzing the cell types, their frequencies, and their individual transcriptional responses within a burn scar versus within Marjolin's ulcer. To achieve this, we conducted single-cell RNA sequencing on two excised tissues: 1. a sample from the center of the tumor (tumor core), and 2. another sample from the margin of tumor-free scar tissue.
Project description:Cannabidiol (CBD) oral spray on murine oral ulcer significantly inhibited inflammation, relieved pain and accelerated healing process. To gain insight into transcriptional regulation of CBD on cells related to healing progress of oral ulcer, we performed RNA-Seq on the immortalized human oral keratinocyte HOK-16B cell lines stimulated with LPS and ATP, after 10μM CBD or vehicle excipient pretreatment.
Project description:Objective: This study aims to investigate the diversity of fibroblasts present in diabetic ulcers and their impact on the wound healing process, as well as to evaluate the effectiveness of Platelet-Rich Plasma (PRP) therapy in the management of diabetic ulcers. Methodology: The single-cell dataset GSE165816 from the GEO database was utilized to analyze DFU-healer and DFU-nonhealer samples in order to evaluate variations in fibroblasts. Functional characteristics of fibroblasts were investigated through analyses of cell communication, transcription factors, and pseudotime analysis. Additionally, a diabetic ulcer rat model was established to compare the therapeutic effects of PRP, followed by histological and transcriptomic sequencing analyses. Result: Single-cell sequencing analysis identified a greater abundance of fibroblasts in the group of diabetic foot ulcer (DFU) patients who exhibited healing. The findings from biological informatics analysis emphasized the critical role of fibroblasts in the wound healing process. Treatment with PRP notably enhanced wound healing in diabetic ulcers in rats, and transcriptomic analysis indicated that gene expression levels post-PRP treatment resembled those of the non-diabetic ulcer group, with a strong association to fibroblasts. Conclusion: Fibroblasts are essential in the process of healing diabetic ulcers, as certain transcription factors have the potential to facilitate wound closure. PRP therapy has been shown to enhance the healing process in diabetic ulcer rat models, possibly through the modulation of gene expression and the promotion of extracellular matrix arrangement. This research offers novel insights and potential therapeutic approaches for managing diabetic ulcers.
Project description:Chronic wounds are a common and costly complication of diabetes, where multifactorial defects contribute to dysregulated skin repair, inflammation, tissue damage, and infection. We previously showed that aspects of the diabetic foot ulcer microbiota were correlated with poor healing outcomes, but many microbial species recovered remain uninvestigated with respect to wound healing. Here we focused onAlcaligenes faecalis, a Gram-negative bacterium that is frequently recovered from chronic wounds but rarely causes infection. Treatment of diabetic wounds withA. faecalisaccelerated healing during early stages. We investigated the underlying mechanisms and found thatA. faecalistreatment promotes re-epithelialization of diabetic keratinocytes, a process which is necessary for healing but deficient in chronic wounds. Overexpression of matrix metalloproteinases in diabetes contributes to failed epithelialization, and we found thatA. faecalistreatment balances this overexpression to allow proper healing. This work uncovers a mechanism of bacterial-driven wound repair and provides a foundation for the development of microbiota-based wound interventions.
Project description:To analyze the gene expression of human gastric epithelial cells (GES-1) regulated by paeonifl or in based on transcript tome sequencing; to identify and analyze key genes; to study the mechanism of paeoniflorin on Leuk-1cells; and to explore its medicinal value. Method: Different doses of Ulcer-healing Decoction were used to treat GES-1, and its activity was assessed by MTT assay. Transcriptome sequencing analysis was then performed to identify differentially expressed genes (DEGs). The function and pathways of the DEGs were annotated using GO and KEGG enrichment analysis. Result: The survival rate of GES-1 cells was significantly increased under different concentrations of ulcer-healing decoction intervention (P < 0.05 or P < 0.01). After 24 hours of treatment with 80 µ g/mL ulcer-healing decoction, a total of 312 crucial DEGs were observed in GES-1 cells, of which 233 DEGs were upregulated and 79 DEGs were downregulated. The top five differentially expressed genes include CYP1A1, IL24, IKBKGP1, GDF15, SCUBE1 and OASL, ADAMTS5, SULF1, ID2, and DDX60. The functions of these genes are mainly related to promoting wound,cell proliferation and migration,immunity and inflammation.GO enrichment analysis showed that the DEGs were significantly enriched in the extracellular region and involved in biological processes such as cytokine production and response, stimulus response, and exerting molecular functions such as proliferation factor receptor activity. KEGG pathway enrichment showed that the DEGs were significantly enriched in various signaling pathways. Immunohistochemistry and other methods were used to detect differentially expressed proteins in GES-1 cells induced by ulcer-healing decoction, and the results were consistent with those from RNA-seq, thereby validating the accuracy of sequencing technologies. Conclusion: The role of ulcer-healing decoction in GES-1 is primarily reflected in regulating inflammatory factors and growth factors, promoting cell proliferation, and supporting the regeneration and repair of gastric mucosal epithelial cells.