Determining the Impacts of Testosterone on S. aureus-induced Skin Damage in Atopic Dermatitis
Grantee: Tamia Harris-Tryon, Associate Professor, UT Southwestern Medical Center, USA
Amount: DKK 2,852,706
Grant category: Research Grants
Year: 2024
Geography: USA
Tamia Harris-Tryon’s study explores atopic dermatitis (AD) which affects seven percent of adults and twenty percent of children. AD has the highest impact on patient quality of life among skin disorders. The pathogenesis of AD is incompletely understood, and there is an increasing appreciation for the contributions of the microbiome. During AD flares, Staphylococcus aureus expands and exacerbates inflammatory responses and skin damage. While S. aureus dominates the skin microbiome in AD, the mechanisms that drive bacterial expansion during inflammation remain unclear. This question is important because skin breakdown in AD is aggravated by S. aureus toxins. S. aureus exotoxins have been shown to stimulate skin inflammation. Tamia Harris-Tryon’s project will test the central hypothesis that testosterone promotes S. aureus-induced skin damage and inflammation in AD as well as investigate how testosterone stimulates S. aureus-induced skin damage in culture and in mouse models. These experiments will also make use of genetically engineered mice with reduced testosterone production in the skin. This approach will reliably determine how testosterone regulates S. aureus-induced skin damage and inflammation.
The results of Tamia Harris-Tryon’s project may reliably determine how testosterone regulates S. aureus-induced skin damage and inflammation.
Viral hijacking of embryonic signaling pathways in trichodysplasia spinulosa
Grantee: Andrzej Dlugosz, Professor, University of Michigan, USA
Amount: DKK 3,985,000
Grant category: Research Grants
Year: 2024
Geography: USA
Andrzej Dlugosz’s project explores how a skin-associated virus called TSPyV can cause a striking hair follicle disorder called trichodysplasia spinulosa. In patients affected by this condition hair follicles on the face and ears are enlarged, structurally abnormal, filled with TSPyV viral particles, and produce spikes instead of hairs. To understand how TSPyV disrupts hair follicle biology Andrzej Dlugosz and his group created genetically engineered mice that express TSPyV viral proteins in skin. These mice produced enlarged and abnormal-appearing follicles and developed follicle-like structures in hairless areas, suggesting that TSPyV can somehow reprogram skin to drive growth of hair follicles which are needed for large-scale virus production. In keeping with this concept, one of the TSPyV viral proteins triggers abnormal activation of an important molecular signal that regulates formation and maturation of hair follicles. The studies will examine hair follicles in trichodysplasia spinulosa using powerful new molecular technologies to better understand the alterations in behavior and maturation of follicle cell types in this disease. They will also investigate how a specific TSPyV protein hijacks an important hair follicle signaling pathway, contributing to the profound changes seen in the skin of trichodysplasia spinulosa patients.
The results of the project have the potential to yield new insights into the regulation of molecular signals controlling formation and growth of hair follicles, based on findings from studying this rare condition.
Ex Vivo Culturing of the Human Skin Microbiome
Grantee: Beth McLellan, Professor, Albert Einstein College of Medicine, USA
Amount: DKK 4,054,452
Grant category: Research Grants
Year: 2024
Geography: USA
Beth McLellan’s project, in collaboration with co-PI and Kosaku Shinoda, explores the functional interactions of live or viable bacteria within the skin microbial community, and their implications in skin disease. The project aims to develop a robust ex vivo model, Skin Microbiome in a Test tube (SMT), to study the dynamic biochemical activity of the viable skin microbiome. Preliminary data indicate that the prototype version of the SMT system (v1) is capable of preserving the diversity of skin bacteria ex vivo. The aims are to (1) refine SMT using Propidium Monoazide (PMA) sequencing to exclusively replicate the viable microbiome and (2) investigate the impact of skin microenvironmental factors (e.g., moisture, sebum levels, and skin breakdown) on the composition and biochemical activity of the viable microbiome, using data from non-invasive sensors at multiple skin sites.
With the generation of the improved version of the SMT (v2), the project hopes to create an innovative platform for functional skin microbiome studies, drug screening and pharmacokinetic modeling with an emphasis on microbial viability leading to individualized treatment strategies based on microbiome community profiles. SMT will serve as a foundation for identifying biomarkers, developing microbiome-based therapies, and improving pharmacokinetic predictions.
Defining how skin microbial communities shape T cell function using a novel antigen-tracking technology
Grantee: Erin Chen, Assistant Professor, Broad Institute of MIT and Harvard, USA
Amount: DKK 3,929,293
Grant category: Research Grants
Year: 2024
Geography: USA
Erin Chen’s project aims to address the fundamental question: how do we translate the composition of our body’s colonizing microbes (our microbiome) into insight about immune function? Commensal bacteria (commonly known as just “commensals”) colonize our skin, over our entire lives, and generate the vast majority of microbe-host encounters, with largely unknown consequences. Erin Chen’s project focuses on commensals’ interactions with T cells because these cells critically impact many aspects of health and disease. Unlike infections, where a single pathogen invades into the tissue, commensals colonize within complex communities and communicate to the host immune system across an intact skin barrier. How the immune system decodes signals from each member of this community is unknown. Erin Chen and her team will address this by colonizing mice with defined communities of commensals and tracking the commensal-derived antigens along with the strain-specific T cells. To do this, they will develop novel methods to detect commensal-derived antigens within the host tissue, at high resolution. By varying the abundance and composition of community members, they aim to discover novel antagonistic, synergistic, and emergent properties of commensal-specific T cells. This work will provide visibility into a currently invisible process: how a lifetime of commensals on our skin are constantly sculpting our T cell function, which ultimately impacts our susceptibility to infections, autoimmunity, and cancer.
Development of novel RNA replicon vectors for treatment of skin genetic disorders
Grantee: Xiaoyang Wu, Associate Professor, University of Chicago
Amount: DKK 4,000,000
Grant category: Research Grants
Year: 2024
Geography: USA
Xiaoyang Wu’s project aims to engineer self-amplifying RNA vector as a platform for gene therapy of recessive X-linked ichthyosis, with potential for treatment of other skin diseases.
Skin ichthyoses are a group of heterogeneous genetic diseases that are characterized by hyperkeratosis, localized or generalized scaling, and often associated with xerosis, hypohidrosis, erythroderma, and recurrent infections. So far, mutations in more than 50 genes have been shown to cause ichthyosis, which affect a variety of different cellular processes, ranging from DNA repair, lipid biosynthesis, cell adhesion, and skin differentiation. Recessive X-linked ichthyosis (RXLI) is the second most common form of inherited ichthyosis. RXLI is caused by mutations in the STS gene on the X chromosome, which encodes microsomal steroid sulfatase. The skin abnormalities of RXLI are caused by the impact of excess cholesterol sulfate, which affects lipid synthesis, organization of the lamellar lipids that provides the skin permeability barrier, corneodesmosome proteolysis, and epidermal differentiation.
As a genetic disorder, RXLI is a life-long condition that can significantly affect domestic life and cause psychological problems for the patients. More effective treatment beyond current symptomatic management is urgently needed. Xiaoyang Wu’s project will explore the possibility that engineered self-amplifying RNA vector can serve as a novel platform for gene therapy of RXLI.
Xiaoyang Wu’s project may serve as proof-of-concept for a novel paradigm for the treatment of patients with genetic skin disorders.
Control of Langerhans cell dynamics and function by the microtubule cytoskeleton
Grantee: Jeffrey Rasmussen, Assistant Professor, University of Washington
Amount: DKK 3,834,520
Grant category: Research Grants
Year: 2024
Geography: USA
Jeffrey Rasmussen’s project investigates the mechanisms governing Langerhans cells’ immune response in wound healing, particularly the role of the microtubule cytoskeleton.
Skin provides a robust and durable physical barrier essential for regulating hydration and repelling pathogens. Damage to skin must be rapidly resolved to maintain organ homeostasis. Epidermal-resident immune cells known as Langerhans cells use dendritic protrusions to dynamically surveil the skin microenvironment, which contains epithelial keratinocytes and somatosensory peripheral axons.
The mechanisms governing Langerhans cell dendrite dynamics and responses to tissue damage are not well understood. Jeffrey Rasmussen and his lab have developed a tractable system using adult zebrafish to study Langerhans cell dynamics. Initial studies using this system revealed several new discoveries, including: 1) that Langerhans cells are the primary phagocyte for degenerating somatosensory axons; 2) Langerhans cells undergo stereotyped responses to local and tissue-scale keratinocyte wounds; and 3) the actin regulator ROCK regulates key aspects of Langerhans cell wound responses. Despite advances in identifying mechanisms of actin function in Langerhans cells, roles for the microtubule cytoskeleton in Langerhans cell biology remain essentially unknown. In preliminary studies, Jeffrey Rasmussen has developed a novel transgenic reporter for microtubules in Langerhans cells and found that the microtubule cytoskeleton dynamically reorganizes during wound responses. His project aims to determine how the microtubule cytoskeleton contributes to the intracellular trafficking and dynamic wound responses of Langerhans cells.
The results of Jeffrey Rasmussen’s project could lead to new fundamental understandings of Langerhans cell biology and dynamics.
Modulating ECM and Immune Responses by Hybrid mRNA Therapeutics for Fetal-like Scarless Wound Healing
Grantee: Wei Tao, Assistant Professor, Brigham and Women's Hospital
Amount: DKK 3,999,996
Grant category: Research Grants
Year: 2024
Geography: USA
Wei Tao’s project explores the biological mechanisms to improve wound healing in adults by mimicking the scarless fetal wound healing process. This project aims to engineer a system that replicates the fetal extracellular matrix and immune responses, using mRNA techniques to produce specific proteins and inhibit biological processes leading to scar formation. This system employs lipid nanoparticles for mRNA delivery and hydrogel for controlled release, enabling spatiotemporal control of key components like collagen type III and interleukin-10, thereby reconstituting fetal-like extracellular matrix organization and modulating over-activated immune responses.
The project’s goals include establishing a foundation for future scarless wound healing studies, developing a hybrid mRNA therapeutic platform for skin defects and diseases, and correlating extracellular matrix and immune modulation with subsequent biological processes and outcomes. This research has promising potential for clinical applications in wound care and other dermatological diseases.
Epigenetic regulation of sebaceous gland development and homeostasis
Grantee: Brian Capell, Assistant Professor, University of Pennsylvania
Amount: DKK 2,885,457
Grant category: Research Grants
Year: 2024
Geography: USA
Brian Capell’s project seeks to better understand how epigenetic changes (modifications that do not change the sequence of genomic DNA) regulate the development of sebaceous glands.
Dysfunction of sebaceous glands (SGs) has been linked to a variety of common skin disorders ranging from atopic dermatitis to acne, sebaceous hyperplasia, seborrheic dermatitis and sebaceous tumors.
Brian Capell and his team have recently discovered that through genetic modification of the epigenome, they could promote a dramatic increase in the number and size of SGs (Ko, et al. Developmental Cell. In press. 2024). This surprising result demonstrated the direct role that epigenetics and chromatin organization plays in controlling SG development and abundance. It also suggested that targeting the epigenome might offer new ways to treat disorders characterized by aberrant SG development and activity.
Diseases related to aberrant SG development or activity can have a deleterious effect on both human physical and mental health. Despite this, very little is known of the role of epigenetics in SG development and homeostasis. To address this, Brian Capell’s project aims to test the influence of epigenomic modifiers and modifications upon SG development and disease to further dissect their contribution to the pathogenesis of these very common conditions.
Collectively, this project will address outstanding questions regarding the role of the epigenome in SG development and homeostasis and in common diseases driven by SG dysfunction – diseases that are both understudied and in need of better therapies.
Endothelial senescence in the pathogenesis of systemic sclerosis
Grantee: Eliza Pei-Suen Tsou, Assistant Professor, University of Michigan
Amount: DKK 3,990,092
Grant category: Research Grants
Year: 2024
Geography: USA
The goal of Eliza Pei-Suen Tsou’s project is to understand the importance of aging endothelial cells (a cell type lining blood vessels) in scleroderma.
Scleroderma is an autoimmune disease characterized by inflammation, scarring of tissues and organs, including the skin, and changes in blood vessels throughout the body.
Most patients experience vascular abnormalities as one of the first symptoms, which trigger tissue stiffness and related complications later in the disease. Although these vascular changes are early critical events, the underlying cause of why they occur has not been determined.
Eliza Pei-Suen Tsou and her team found that dermal endothelial cells from scleroderma patients function differently compared to healthy controls. In particular, these cells undergo senescence, which is a process by which a cell ages but does not die off when it should. Over time, large numbers of senescent cells build up in the body. These cells remain active and release harmful substances that may cause inflammation and damage to nearby healthy cells.
In this project, Eliza and the team aim to determine the cause for vascular abnormalities in scleroderma, with a specific focus on how senescence is involved. They hypothesize that endothelial cell senescence is fundamental in causing the disease and might be targeted for therapy. Specifically, they propose that endothelial senescence accounts for the abnormality of endothelial cells in scleroderma, resulting not only in blood vessel changes but also in tissue scarring.
The goal is to determine why the endothelial cells acquire the senescent phenotype, and what this senescent phenotype does to promote the disease.
This project may form the basis for novel approaches to treating scleroderma.
Understanding structural and functional differences between JAK family JH1 and JH2 domains
Grantee: Christopher Bunick, Associate Professor, Yale University
Amount: DKK 4,165,955
Grant category: Research Grants
Year: 2024
Geography: USA
Christopher Bunick’s project aims to improve and substantiate our current knowledge of the structure and function of Janus kinases (JAKs) to improve safety and efficacy when developing new JAK inhibitors.
Janus kinase (JAK) inhibitors are small molecule drugs that treat inflammatory dermatological conditions by inhibiting cytokine signaling. Currently targeted diseases include atopic dermatitis, psoriasis, hand eczema, alopecia areata, vitiligo, and hidradenitis suppurativa.
Optimal JAK inhibitor matching to dermatologic disease remains challenging because of cross reactivity among four related JAK kinases: JAK1, JAK2, JAK3 and TYK2. Each possesses catalytic kinase (JH1) and allosteric (JH2) domains (an allosteric domain is a site where binding of a molecule indirectly modulates the function of the protein, here the catalytic activity). Both JH1 and JH2 domains have been targeted for drug development, yet a scientific knowledge gap exists as to how the allosteric JH2 domain regulates catalytic JH1 function and the subsequent downstream activation of signal transducer and activator of transcription (STAT) proteins.
A barrier for JAK inhibitor prescription is its promiscuity; it may target more than one JAK, leading to broader cytokine suppression than desired. This poor selectivity is likely rooted in suboptimal drug discovery procedures emphasizing inhibitory capacity over selectivity, resulting in unexpected real-world side effects, including malignancy, cardiovascular events, and thrombosis.
Christopher Bunick and his team will use AI-based generative modeling, molecular dynamics, computational biophysics, structural biology, and biochemistry to (i) determine how JH2 allosterically regulates JH1; (ii) define the structural basis for enhancing selectivity against specific JAK domains; (iii) elucidate downstream mechanisms regulating STAT signaling; and (iv) elucidate molecular properties of JAKs beyond JH1/JH2 domains.
This project may pave the way for better and safer treatment of skin diseases using JAK inhibitors.