Targets of Retinoic Acid (RA) were identified in primary human epidermal keratinocytes grown in the presence or absence of all-trans retinoic acid for 1, 4, 24, 48 and 72 hours. Targets of Thyroid Hormone (T3) were identified in primary human epidermal keratinocytes grown in the presence or absence of the hormone; same controls as for RA.
Retinoid-responsive transcriptional changes in epidermal keratinocytes.
Specimen part
View SamplesChronic non-healing venous leg ulcers (VLUs) are a widespread debilitating disease with high morbidity and associated costs, as approximately $15 billion annually are spent on the care of VLUs. Despite their socioeconomic burden, there is a paucity of novel treatments targeted towards healing VLUs, which can be attributed to both lack of pathophysiologic insight into VLU development as well as lack of knowledge regarding biologic actions of VLU-targeted therapies. Currently, the bioengineered bilayered living cellular construct (BLCC) skin substitute is the only FDA-approved biologic treatment for healing VLUs. To elucidate the mechanisms through which the BLCC promotes healing of chronic VLUs, we conducted a clinical trial (NCT01327937) in which patients with non-healing VLUs were treated with either standard care (compression therapy) or with BLCC together with standard care. Tissue was collected from the VLU edge before and 1 week after treatment, and samples underwent comprehensive microarray, mRNA and protein analyses. Ulcers treated with BLCC skin substitute displayed three distinct patterns suggesting the mechanisms by which BLCC shifted a non-healing into a healing tissue response: it modulated inflammatory and growth factor signaling; it activated keratinocytes; and it attenuated Wnt/-catenin signaling. In these ways, BLCC application orchestrated a shift of the chronic non-healing ulcer microenvironment into a distinctive healing milieu resembling that of an acute, healing wound. Our findings also provide first patient-derived in vivo evidence of specific biologic processes that can be targeted in the design of therapies to promote healing of chronic VLUs.
A bioengineered living cell construct activates an acute wound healing response in venous leg ulcers.
Specimen part, Disease stage, Time
View SamplesGlucocorticoids (GCs) have a long history of use as therapeutic agents for numerous skin diseases. Surprisingly, their specific molecular effects are largely unknown. To characterize GC action in epidermis, we compared the transcriptional profiles of primary human keratinocytes untreated and treated with dexamethasone (DEX) for 1, 4, 24, 48 and 72 hours using large-scale microarray analyses. The majority of genes were found regulated only after 24 hours and remained regulated throughout the treatment. In addition to expected anti-inflammatory genes, we found that GCs regulate cell fate, tissue remodeling, cell motility, differentiation and metabolism. GCs not only effectively block signaling by TNF-alpha and IL-1 but also by IFN-gamma, which was not previously known. Specifically, GCs suppress the expression of essentially all IFN-gamma-regulated genes, including IFN-gamma receptor and STAT-1. GCs also block STAT-1 activation and nuclear translocation. Unexpectedly, GCs have anti-apoptotic effects in keratinocytes by inducing the expression of anti-apoptotic and repressing pro-apoptotic genes. Consequently, GCs treatment blocked UV-induced apoptosis of keratinocytes. GCs have a profound effect on wound healing by inhibiting cell motility and the expression of pro-angiogenic factor VEGF. They play an important role in tissue remodeling and scar formation by suppressing the expression of TGF-beta-1 and -2, MMP1, 2, 9 and 10 and inducing TIMP-2. Finally, GCs promote terminal stages of epidermal differentiation while simultaneously inhibiting the early stages. These results provide new insights into the beneficial and adverse effects of GCs in epidermis, defining the participating genes and mechanisms that coordinate the cellular responses important for GC-based therapies.
Novel genomic effects of glucocorticoids in epidermal keratinocytes: inhibition of apoptosis, interferon-gamma pathway, and wound healing along with promotion of terminal differentiation.
Specimen part, Treatment
View SamplesDiabetic foot ulcers (DFUs) are the leading cause of lower leg amputations in diabetic population. To better understand molecular pathophysiology of DFUs we used patients specimens and genomic profiling. We identified 3900 genes specifically regulated in DFUs. Moreover, we compared DFU to human skin acute wound (AW) profiles and found DNA repair mechanisms and regulation of gene expression among the processes specifically suppressed in DFUs, whereas essential wound healing-related processes, inflammatory/immune response or cell migration, were not activated properly. To identify potential regulators of DFU-specific genes, we used upstream target analysis. We found miR-15/16 family enriched in DFUs, but not in AW, which was confirmed by qPCR. We found that infection with the most common DFU colonizer, Staphylococcus aureus, triggers induction of miR-15-5p, which in turn, targets multiple DFU-specific genes, including genes involved in DNA repair (WEE1, MSH2 and RAD50) and the regulator of inflammatory pathway, IKBKB. Induction of miR-15b-5p, either by miR-mimic transfection in vitro or by S. aureus infection of acute wounds ex vivo, suppressed both WEE1 and IKBKB. Consequently, we detected an increase in DNA double strand breaks in DFUs. In summary, our data indicate that S. aureus infection, via induction of miR-15b-5p, may lead to suppression of DNA repair mechanisms and a sub-optimal inflammatory response, contributing to pathophysiology of DFU patients
Staphylococcus aureus Triggers Induction of miR-15B-5P to Diminish DNA Repair and Deregulate Inflammatory Response in Diabetic Foot Ulcers.
Specimen part, Disease, Disease stage
View SamplesGlobal gene expression analysis of FD-iPSC and deribved neural crest cells
Modelling pathogenesis and treatment of familial dysautonomia using patient-specific iPSCs.
Specimen part
View SamplesThe pathways involved in hierarchical differentiation of human embryonic stem cells (hESC) into abundant and durable endothelial cells (EC) are unknown. We employed an EC-specific VE-cadherin promoter driving GFP (hVPr-GFP) to screen for factors that augmented yields of vascular-committed ECs from hESCs. In phase 1 of our approach, inhibition of TGFb, precisely at day 7 of hESC differentiation, enhanced emergence of hVPr-GFP+ ECs by 10-fold. In the second phase, TGFb-inhibition preserved proliferation and vascular identity of purified ECs, resulting in net 36-fold expansion of homogenous EC-monolayers, and allowing transcriptional profiling that revealed a unique angiogenic signature defined by the VEGFR2highId1highVE-cadherin+EphrinB2+CD133+HoxA9- phenotype. Using an Id1-YFP hESC reporter line, we showed that TGFb-inhibition sustained Id1 expression in hESC-derived ECs, which was required for increased proliferation and preservation of EC commitment. These data provide a multiphasic method for serum-free differentiation and long-term maintenance of authentic hESC-derived ECs, establishing clinical-scale generation of transplantable human ECs.
Expansion and maintenance of human embryonic stem cell-derived endothelial cells by TGFbeta inhibition is Id1 dependent.
Specimen part
View SamplesA study of diabetic neuropathy in dorsal root ganglia from streptozotocin-diabetic male wistar rats over the first 8 weeks of diabetes
Identification of changes in gene expression in dorsal root ganglia in diabetic neuropathy: correlation with functional deficits.
Sex, Age, Specimen part, Disease, Disease stage, Time
View SamplesWe previously found a short sleeper mutant, fmn, and identified its mutation in the dopamine transporter gene. In an attempt to discover additional sleep related genes in Drosophila, we carried out a microarray analysis comparing mRNA expression in heads of fmn and control flies and found differentially expressed genes.
The NMDA Receptor Promotes Sleep in the Fruit Fly, Drosophila melanogaster.
Sex, Specimen part
View SamplesGene expression profiling reveals functional difference between Sq and HH-Sq on differentiation, metabolism, and lipid droplot formation of dADSC
New Amphiphilic Squalene Derivative Improves Metabolism of Adipocytes Differentiated From Diabetic Adipose-Derived Stem Cells and Prevents Excessive Lipogenesis.
Specimen part, Disease, Disease stage
View SamplesIdentification of temporal changes in gene expression in macrophages isolated from the site of nerve injury. Overall design: Macrophages were profiled at 3 timepoints (5, 14, and 28 days) after nerve injury with 2-3 independent biological replicates per timepoint.
Temporal changes in macrophage phenotype after peripheral nerve injury.
Subject, Time
View Samples