Citrullination in hair growth and alopecia

Grantee: Maria Genander, Assistant Professor, Karolinska Institutet

Amount: DKK 4,020,645

Grant category: Research grants in open competition

Year: 2023

Geography: Sweden

Maria Genander’s project aims to understand the physiological role of the enzymes PADI3 and PADI4, which convert the amino acid arginine to citrulline, in normal hair growth – to ultimately better understand the changes that happen during unwanted hair loss, alopecia.

Hair follicle (HF) growth, leading to the generation of the hair shaft, requires coordinated development of the cells that make up hair. Protein modifications act to fine-tune the action of the signaling that leads to cellular maturation and differentiation and impacts directly on the properties of structural proteins required for hair formation. In this project, Maria Genander and her team investigate the expression of the protein-modifying enzymes PADI3 and PADI4 in the HF to understand the functional impact of PADI-mediated citrullination on cell differentiation and hair growth. Preliminary data indicate that PADI4 restricts proliferation of HF progenitor cells committed to the hair shaft lineage. Using sophisticated methodology, they aim to decipher mechanistically how PADI4 influences HF lineage progression. In addition, they will use in-utero lentiviral injections in mice to probe the function of PADI3a and PADI3b to understand how distinct PADI3 isoforms impacts hair formation and the development of alopecia.

Collectively, Maria Genander’s work will focus on addressing citrullination in hair follicle growth and hair formation. Understanding normal hair follicle development is a prerequisite for development of therapeutic strategies targeting alopecia.

Understanding the role of FOXO4-mediated regulatory network in the biology of Th22 cells

Grantee: Kilian Eyerich, Chief Physician, Karolinska Institutet

Amount: DKK 2,045,000

Grant category: Research grants in open competition

Year: 2023

Geography: Sweden

Kilian Eyerich’s project aims to investigate the role of the transcription factor FOXO4 in the development of a specific type of T cells – the Th22 cells.

Th22 cells are a distinct subset of CD4+ T helper cells, and their effector cytokine IL-22 plays a protective role in barrier homeostasis by regulating innate immune responses, antimicrobial defense mechanisms, and wound healing. The natural differentiation of naive CD4+ T cells into the Th22 lineage and production of IL-22 by these cells is a multifactorial process that is not yet fully understood. In this project, Kilian Eyerich, along with colleague Kunal Das Mahapatra and team, will investigate the hypothesis that the transcription factor FOXO4 is a novel regulator of IL-22 production in Th22 cells. Pilot data show that FOXO4 is upregulated in human skin derived Th22 clones. It has a pattern of early induction and steady increment during Th22 differentiation, which is governed by the cytokines IL-6 and TNF-a. Moreover, the team has shown that silencing FOXO4 in naive T cells in a

Th22-inducing condition leads to reduced IL-22 secretion and that there is a protective effect of this regulation on epithelial cells, as observed in a scratch assay where keratinocytes, cultured in the supernatant from FOXO4-depleted T cells, migrated less efficiently.

The proposed project therefore aims to perform a deeper characterization of FOXO4 in Th22 cells by systematically identifying FOXO4-regulated genes, downstream pathways, and potential co-factors. In addition, the extrinsic role of FOXO4 on keratinocytes and skin wound healing will be assessed by ex vivo assays and analysis of multi-omics data from human patients.

Taken together, this project may offer novel insights into the regulatory processes in development and function of Th22 T cells.

Deciphering the mechanistic underpins of the inflammation-to-proliferation phase transition in human skin wound healing

Grantee: Ning Xu Landén, Associate Professor, Karolinska Institutet

Amount: DKK 4,164,510

Grant category: Research grants in open competition

Year: 2022

Geography: Sweden

Ning Xu Landén’s project seeks to improve wound healing by identifying key regulators of cellular transition from inflammation to proliferation, a cardinal event during normal skin wound healing which is lacking in chronic wounds.

Ning and her team will approach this by mapping the spatiotemporal changes, both genetic, molecular and cellular, happening during the healing of acute wounds. Using this mapping, she and her team will then aim to identify the core genetic changes and intercellular crosstalk which regulates the inflammation to proliferation transition. Once identified, these changes and intercellular crosstalk will be characterized in more detail.

The ultimate goal is to identify the “master” regulators of inflammation-to-proliferation transition in order to improve and accelerate wound healing and thus minimize the risk of development of chronic wounds.

If successful, this project could pave the way for a novel approach to wound healing which may also eventually reduce subsequent scarring.

New therapy and diagnostics of psoriasis vulgaris and psoriatic arthritis based on new animal models

Grantee: Rikard Holmdahl, Professor, Karolinska Institutet

Amount: DKK 3,622,500

Grant category: Research grants in open competition

Year: 2022

Geography: Sweden

Rikard Holmdahl and his team have discovered that mannan, a large natural sugar molecule found in yeast and plant cell walls, can induce a psoriasis-like condition in mice which strongly resembles human disease in terms of both genetics and clinical presentation.

The aim of Rikard’s research is to investigate the potential of this animal model to improve our understanding of disease mechanisms, predict disease progression and potentially treat psoriasis and psoriatic arthritis by modifying the sugar structure of mannan – hereby increasing the cellular level of reactive oxygen species which appears to be protective against disease development and progression.

In addition, Rikard’s team aims to identify new diagnostic (auto-)antibodies, found both in the mannan-induced psoriasis (MIP) mouse model and in a cohort of psoriatic arthritis patients, to improve early diagnosis and hence improve intervention.

If successful, the results could provide a new and more exact tool to further investigate what causes psoriasis and psoriasis arthritis, while at the same time potentially improving the efficiency of early diagnosis and subsequent treatment.

Protein aggregation in host defense and skin inflammation

Grantee: Artur Schmidtchen, Professor, Dermatology and Venereology, Department of Clinical Sciences, Lund University

Amount: DKK 2,100,000

Grant category: Research grants in open competition

Year: 2020

Geography: Sweden

The primary goal of this project is to identify and characterize the ‘aggregatome’, which describes the complete and complex network of proteins that are involved in the specific mechanism where the body – via its immune system – protects itself e.g. from bacteria. Subsequently, the project will explore and define the roles of the ‘aggregatome’ in inflammatory skin diseases.

The ultimate goal is to obtain new and deeper understanding of diseases affected by protein aggregation and potentially identify biomarkers of diagnostic significance.

Deciphering the Role of Non-Coding RNAs in Epidermal Carcinogenesis

Grantee: Andor Pivarcsi, Senior lecturer/Associate Professor, Department of Medical Biochemistry and Microbiology (IMBIM), Uppsala Universitet, Uppsala

Amount: DKK 4,164,300

Grant category: Research grants in open competition

Year: 2020

Geography: Sweden

The goal of this project is to investigate the potential role of long non-coding RNAs (lncRNAs, RNA molecules, which do not function through coding for protein, but by regulating other genes) in the development of the most common form of skin cancer with metastatic potential – Squamous Cell Carcinoma (SCC). Such RNAs are known to be key regulators of multiple cellular functions, tissue development and homeostasis, but their role in SCC is not clear. Andor Pivarcsi and his team have identified a group of long non-coding RNAs that have altered expression in this disease. As these lncRNAs may prove to be key players both in the development of cutaneous cancers and in the maintenance of normal skin homeostasis, they now want to investigate their function.

Andor Pivarcsi and his team will do so by defining the role and mechanism of action of selected lncRNAs by a combination of methods, including inhibiting them with anti-sense oligonucleotides, that will effectively prevent their association with natural binding partners. The results will improve our understanding of long non-coding RNAs in cutaneous malignancies and may pave the way towards improved antisense oligonucleotide-based skin cancer therapy.

Andor Pivarcsi is a former LEO Foundation Silver Award Winner (2010).

The LEO Foundation Award 2020 – Region EMEA

Grantee: Dr. Ning Xu Landén

Amount: USD 100,000

Grant category: LEO Foundation Awards

Year: 2020

Geography: Sweden

Ning Xu Landén is an Associate Professor in experimental dermatology and venereology at the Department of Medicine, Solna at the Karolinska Institute in Sweden where she leads a successful research group. She is the author of around 50 scientific articles with more than 3000 citations.

Ning Xu Landén receives the award in recognition of her high impact research in wound healing.

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Molecular body map of human skin: the key for understanding human skin diseases

Grantee: Maria Kasper, Principal Investigator, Karolinska Institutet, Stockholm

Amount: DKK 3,949,807

Grant category: Research grants in open competition

Year: 2019

Geography: Sweden

Skin is the largest human organ and contains an intricate variety of cell types that assure tissue architecture and proper skin function, such as thermoregulation and hair growth.

An imbalance of cell types and/or molecular signalling often results in disease. Across the body, skin composition differs in thickness, hair growth, sebaceous and sweat gland density, microbiota exposure and disease susceptibility.

However, a molecular understanding of how cell types and genetic programs vary with skin regions, and molecular alterations in disease, is currently lacking.

Previously, my lab pioneered the use of single-cell RNA-seq (scRNA-seq) in mouse skin by generating a comprehensive molecular and spatial atlas of epithelial and mesenchymal cells during hair growth and rest (Joost et al. 2016; Joost et al. 2019). Building upon our expertise, we will molecularly dissect human skin, initially through a body map that spans various body sites of healthy donors, to identify cell types and sub types in human skin and also to investigate important cell type differences and alterations compared to mouse skin. Subsequently, the body map will be the foundation for molecular analyses of skin diseases, including immune-triggered psoriasis.

A carefully constructed and annotated human skin atlas, with spatial and molecular precision, would have enormous value for the scientific community and propel our molecular understanding of skin in health and disease.

The LEO Foundation Award 2017 – Gold Award

Grantee: Dr. Maria Kasper

Amount: DKK 1,000,000

Grant category: LEO Foundation Awards

Year: 2017

Geography: Sweden

The Gold Award went to Dr. Maria Kasper, presently leading a research group at the Karolinska Institute in Stockholm, Sweden.

“Receiving the phone call with the news of the LEO Foundation 2017 Gold award is one of these few unforgettable moments. My friends often call me “skin nerd” since I love everything about skin.  Thus, it’s such a happiness and great honour for me to receive this prestigious prize. I would like to express my deepest thank you to the LEO Foundation, the ESDR, and my lab members who make everyday’s work fun and colorful,” said Maria Kasper.

The LEO Foundation Award 2010 – Silver Award

Grantee: Dr. Andor Pivarcsi

Amount: DKK 500,000

Grant category: LEO Foundation Awards

Year: 2010

Geography: Sweden

Presented to Dr. Andor Pivarcsi, young dermatology researcher at the Karolinska Institute in Sweden for his investigation of the role of microRNAs (miRNA) in skin disease.

Dr.Pivarsci’s work centres on miRNAs, a class of recently discovered small RNA molecules, shown to play a critical role in controlling genes behaviour. His research is expected to contribute significantly to our understanding of the pathological mechanisms in skin diseases, such as psoriasis and cancer.