Neutron reflectivity of healthy and atopic dermatitis lesional skin lipid models

Grantee: Kathryn Browning, LEO Foundation Centre for Cutaneous Drug Delivery (LFCCDD), Department of Pharmacy, University of Copenhagen

Amount: DKK 2,234,415

Grant category: Research Grants in open competition

Year: 2018

Geography: Denmark

Atopic dermatitis (AD) is a chronic disorder caused by the improper function of the skins barrier layer, the stratum corneum (SC). It is thought to affect between 15 and 30% of children and up to 10% of adults.

The need to develop drugs and drug delivery vehicles which effectively, and possibly specifically, interact with the compromised skin of AD patients is of great importance.

However, to date most pre-clinical trials utilise healthy skin, excised from surgical procedures, to investigate the penetration and interactions of drugs targeted to skin disease. This approach does not accurately represent lesional or diseased stratum corneum.

This project aims to develop models of the stratum corneum to compare the lipid multilayer structure and interactions of healthy and atopic dermatitis (AD) lesional stratum corneum. Key to the success of these models is access to a wide variety of skin lipids not commercially available and crucial to the realistic self-assembly of the lipid multilayers observed in SC.

An example of a currently unavailable lipid is the long chain esterified ceramides, Ceramide[EOS], which has been linked to the formation of long periodicity phases and lower permeability in SC and is often deficient in AD patients.2-4 These lipids will be obtained by extraction, separation and purification of ceramides from pig skin SC. Lipid mixtures of ratios found in healthy and AD lesional skin will then be self-assembled on a solid support and investigated for interactions with drugs and drug delivery vehicles using neutron reflection, which offers unique opportunities for angstrom level structural resolution and, through selective deuteration, the ability to highlight specific components of the system to improve contrast.

Impaired thymic negative selection as a source of melanoma-reactive TCR specificities

Grantee: Kai Kisand, University of Tartu, Institute of Biomedicine and Translational Medicine

Amount: DKK 4,908,566

Grant category: Research Grants in open competition

Year: 2018

Geography: Estonia

Melanoma is a very aggressive type of cancer that affects people at their most productive period of the life. As most of the diagnosed patients should have a long life still ahead a cure of the disease is highly desired.

Cancer immunotherapy with checkpoint inhibitors and T cell adoptive therapy have established the crucial role of T cell responses in melanoma as well as in many other cancers. Successful immunotherapy of melanoma is often associated with vitiligo as a side effect indicating the importance of targeting the antigenic epitopes that are shared between melanocytes and melanoma cells.

However, melanocyte antigens are “self” and T cell receptor (TCR) specificities that recognise such epitopes with high affinity are deleted during their maturation in the thymus. To find high-affinity TCRs specific for melanocyte/melanoma antigens we will interrogate the TCR repertoire of a patient population that is defective in their central (thymic) tolerance induction mechanisms due to mutations in autoimmune regulator gene, and who develop vitiligo as one of their disease manifestations.

We expect to identify several TCR specificities that recognise melanocyte/melanoma antigenic epitopes. This information can be used for designing genetically modified T cells for adoptive treatment of melanoma patients, and to advance the knowledge about vitiligo pathogenesis and mechanisms of central tolerance induction.

Local targeted immunotherapy for treatment of squamous cell carcinomas

Grantee: Merete Hædersdal, Bispebjerg Hospital

Amount: DKK 2,358,825

Grant category: Research Grants in open competition

Year: 2018

Geography: Denmark

Squamous cell carcinoma (SCC) together with basal cell carcinoma comprises the absolute majority of non-melanoma skin cancers, affecting 150,000 persons in Denmark, equivalent to 3% of the population.

SCC’s cost is consequently substantial, reflected by notable patient morbidity, heavy socioeconomic burdens and significant mortality in immunosuppressed populations.

In oncology, systemic immunotherapies with PD1 and CTLA4 antibodies have had revolutionizing impact on clinical cancer treatment. Recognizing the immense potential of these strategies also for SCC, our vision is to pioneer a new local treatment approach by harnessing the immune system to combat SCC, while at the same time avoiding side effects associated with systemic treatment.

In a three-tiered translational project, we thus aim to deliver PD1 and CTLA4 antibodies through the skin using ablative fractional laser (AFL), effectively opening the door to implementation of topical SCC immunotherapy. The project is executed in collaboration with the Wellman Center at Harvard Medical School and Center for Cancer Immune Therapy at Herlev Hospital. The 3-year research plan comprises preclinical studies on biodistribution and pharmacokinetics in healthy skin, a proof-of-concept study in a well-established murine model for human SCC, and an explorative clinical study in SCC patients from the skin cancer clinic at Bispebjerg Hospital. For patients, topical immunotherapy may constitute a safe treatment with decreased morbidity and the prospect of potentially reduced risk of future SCC occurrence. This in turn will lower the socioeconomic burden of repeated treatments for a large cancer patient group, including high-risk immunosuppressed patients such as organ transplant recipients.

Probing the function of melanosomal transporters in pigmentation using metabolic profiling

Grantee: David M. Sabatini, Whitehead Institute of Biomedical Research

Amount: DKK 1,278,270

Grant category: Research Grants in open competition

Year: 2018

Geography: USA

Studies in human populations have identified dozens of pigmentation genes, many of which encode proteins with well-understood functions, such as in melanocyte development, melanin biosynthesis, and the biogenesis and trafficking of specialized melanin-containing organelles called melanosomes.

Yet, there are other pigmentation genes that we know much less about, such as those that encode putative transporter proteins on the melanosome surface. These putative melanosomal transporters have been reported to import precursor metabolites for melanin synthesis or regulate melanosomal pH; however, many of these findings have been controversial or speculative. Deciphering the molecular function of these putative transporters and their physiological substrates is crucial to our understanding of pigmentation.

To address this problem, we propose to determine the metabolite composition of melanosomes and define the role of individual transporters in melanosomal function. We will develop a purification method to rapidly isolate intact melanosomes and analyse them by liquid chromatography and mass spectrometry to compile the first catalog of melanosomal metabolites. We will subsequently characterize SLC45A2, a putative melanosomal transporter that modulates human pigmentation in response to sunlight. By comparing the metabolite profile of wild-type versus SLC45A2-deficient melanosomes, we will identify candidate SLC45A2 substrates and validate them using biochemical assays, a workflow that will be applied to other putative melanosomal transporters.

This study will present the first detailed analysis of melanosome metabolites, as well as identify key metabolites and their transporters essential for melanogenesis. This work could inform new ways to modulate pigmentation and treat pigmentation pathologies.

Nucleic Acid Ionic Liquids (NAILs) for Topical Skin Applications

Grantee: Samir Mitragotri, Harvard John A. Paulson School of Engineering and Applied Sciences

Amount: DKK 2,000,043

Grant category: Research Grants in open competition

Year: 2018

Geography: USA

We will develop a novel ionic-liquid formulation for topical delivery of nucleic acids into the skin.

Our ionic liquid enhances lipophilicity of nucleic acids by ~100,000,000 fold and enhances their penetration into the skin. We will demonstrate the feasibility of the platform through delivery and efficacy of two siRNAs. The resulting platform is expected to have broad applications to other nucleic acid drugs including mRNA for the treatment of a wide range of dermatological conditions.

Our ionic liquid platform will open new opportunities for the treatment of dermatological conditions.

Investigating the role of human periostin in healthy skin and severe eczema

Grantee: Jan J. Enghild, Aarhus University

Amount: DKK 3,045,231

Grant category: Research Grants in open competition

Year: 2018

Geography: Denmark

Severe eczema, also known as atopic dermatitis (AD) is the most common inflammatory skin disease resulting in itchy, inflamed, and swollen skin that is very susceptible to infection. It is estimated that 15-20% of all children and 2-10% of adults are affected, without effective treatment.

Because of this, significant public health burden and the lack of safe and effective treatments, there is a need for novel targeted therapeutics that can help manage symptoms and improve the quality of life for the patients.

The protein periostin is expressed in the skin and is implicated in AD. Significantly, studies have shown that the elimination of periostin in an AD mouse model reduces or completely removes the symptoms making periostin an apparent therapeutic target. However, the physiological functions of periostin remains unclear and a reduction or elimination of the protein in the skin could have severe side effects.

Therefore, a deeper understanding of the physiological role in healthy and diseased skin must be established. The interdisciplinary research team behind this project propose to address these issues and establish the function of periostin using in vitro and in vivo experimental setups including primary cell cultures, zebrafish, mouse models and human specimens combined with advanced biochemical methods. Novel therapeutics are urgently needed, and this project aim is to establish a strategy for the development of new treatment paradigms for AD, leading towards novel, innovative therapeutic strategies.

Endosomal Chemokine Receptor Signaling as Basis for Metastasis in Malignant Melanoma

Grantee: Alex Rojas Bie Thomsen, Columbia University Medical Center

Amount: DKK 3,600,308

Grant category: Research Grants in open competition

Year: 2018

Geography: USA

Melanoma is the deadliest form of skin cancer with few treatment options to patients with advanced metastatic disease.

Melanoma metastasis to lymph nodes is associated with expression of the chemokine receptor CCR7, a member of the G protein-coupled receptors (GPCRs) superfamily that promote cell migration of immune cells. Classically, upon agonist stimulation, GPCRs at the cell membrane activate heterotrimeric G proteins, causing downstream signaling throughout the cell. In order to terminate G protein signaling, cells have devised a specialized desensitization mechanism that includes receptor phosphorylation by GPCR kinases and subsequent recruitment of β-arrestins (βarrs) to the phosphorylated receptors. The GPCR–βarrs interaction both blocks the G proteinbinding site and promotes receptor endocytosis.

However, we recently discovered that some GPCRs interact with G proteins and βarrs simultaneously to form GPCR–G protein–βarr ‘megaplexes’, which allows the receptor to continue to stimulate G protein signaling while being internalized into endosomes by βarrs. Our preliminary results suggest that CCR7 forms megaplexes and promotes G protein signaling from internalized compartments. Interestingly, endosomal signaling, in general, is highly involved in cell migration, and different proteins are trafficked between plasma membrane and endosomes during this process. Thus, the proposed project aims to investigate the involvement of endosomal CCR7 signaling in melanoma cell migration. Furthermore, using a combination of highly advanced cryo-electron tomography and APEX2 proteomics, we will visualize the mechanism of CCR7-mediated melanoma cell migration protein-by-protein. Such detailed mechanistic knowledge will assist in designing innovative therapeutics to treat metastatic malignant melanoma.

Developing a Cell-Based Therapy for Alopecia

Grantee: George Cotsarelis, Perelman School of Medicine, University of Pennsylvania, Philadelphia

Amount: DKK 3,793,808

Grant category: Research Grants in open competition

Year: 2018

Geography: USA

Androgenetic alopecia (AGA, Male or Female Pattern Baldness) is the most common type of hair loss, affecting approximately 50% of men and 30% of women by the age of 50.

Current therapies, including pharmaceutical and surgical interventions, are either marginally effective or expensive with significant limitations. Over the last decade, breakthroughs made in the field of adult stem cells have laid the foundation for a cell-based approach to tissue and organ regeneration. Cell-based therapies will comprise a new wave of medical breakthroughs.

In this study we propose to produce human hair follicles from induced pluripotent stem (iPS) cells by directing these cells to form the two types of cells that are needed for human hair formation, namely the human hair follicle epidermal cells and the hair inductive dermal fibroblasts.

We will combine our hair biology and tissue-engineering expertise to generate early stage human hair follicles in culture that can be implanted into an animal model to grow into a mature hair. The long-term goals are to develop an innovative cell-based treatment for hair loss and an in vitro platform for testing hair growth compounds.

Psoriasis: a microbiome-driven disease?

Grantee: Patrick Zeeuwen, Radboud University Medical Center, Nijmegen

Amount: DKK 2,545,944

Grant category: Research Grants in open competition

Year: 2018

Geography: Netherlands

Psoriasis is highly prevalent and has a significant medical and socio-economic impact.

The prevailing dogma has been that abnormalities of the adaptive immune system were primary, but genetic studies have highlighted the importance of local skin-specific factors. We and others have identified epidermis-specific innate immunity genes, like beta-defensins and Late Cornified Envelope (LCE) genes, to be associated with disease development.

We recently made two exciting observations. First, deletion of LCE3B and LCE3C does not merely imply the loss of two genes but has a genomic effect that leads to a strong induction of the flanking LCE3A gene. Secondly, we found that LCE proteins, and LCE3A in particular, have broad-spectrum antimicrobial activity. We hypothesize that the LCE3B/C-del status affects the cutaneous host defense repertoire thereby shaping the skin microbiome. We aim to investigate the biology of LCE genes and to translate these findings to our understanding of psoriasis pathogenesis.

Key objectives are to:

  1. assess the antimicrobial activity and specificity of all LCEs and their synergy with other antimicrobial proteins. This will be investigated by metagenomic approaches and classical in vitro microbiological assays, using recombinant and synthetic LCE proteins and peptides derived thereof
  2. investigate LCE3B/C-del in isogenic 3D-skin equivalents in vitro generated from the immortalized human keratinocyte N/TERT cell line. Deletions of other LCE genes or their regulatory sequences will be made using CRISPR/Cas9 technology. Effects on epidermal biology relevant to psoriasis will be studied and include antimicrobial host defense, innate immune response and skin barrier function

Investigating the tumor suppressive functions of Notch signaling during skin cancer initiation and progression

Grantee: Sunny Y. Wong, Assistant Professor, University of Michigan, Ann Arbor

Amount: DKK 2,486,354

Grant category: Research Grants in open competition

Year: 2018

Geography: USA

Basal cell carcinoma (BCC) is the world’s most common cancer and is defined by uncontrolled activation of the Hedgehog (Hh) signaling pathway.

Although previous studies have suggested that elevated Hh may be sufficient for BCC formation, mutations in the Notch pathway are also commonly observed. Furthermore, Notch-deficient mice are susceptible to forming BCCs, and our recent studies have shown that Notch can modulate tumor-drug response.

These studies seek to understand whether Notch affects multiple aspects of BCC tumorigenesis. Using a combination of animal studies and human BCC specimens, we will investigate how Notch modulates tumor progression and stem cell origin.

We will also model in mice a recent clinical trial, where Alzheimer’s patients treated with a Notch inhibitor reported increased incidence of BCC. We hypothesize that Notch may suppress tumorigenesis at multiple levels by controlling cell differentiation, apoptosis and turnover, similar to its function in normal skin and hair follicles.

These studies will ultimately build on the novel premise that BCCs may originate from a precursor lesion. Given that Notch mutations are the most commonly observed genetic aberrations in human skin, a deeper understanding of the tumor suppressive properties of this pathway is urgently needed.