Barrier function of the skin

The skin provides an essential barrier for our body. It prevents the invasion of pathogens, allergens and other xenobiotics as well as the loss of water and solutes. Impairment of skin barrier function can be cause of several skin diseases or aggravate them.

  • The skin barrier is composed of several components: the mechanical barriers of the stratum corneum and the tight junctions (TJs), the microbiome barrier, the immunological barrier which comprises immune cells and cytokines, and the chemical barrier which comprises antimicrobial peptides. These barriers interact with each other and an alteration of a distinct barrier influences the others.

    The skin barrier plays an important role in skin diseases. For example, it is known that a skin barrier defect is causative for atopic dermatitis and results in a vicious circle: Impaired skin barrier leads to increased uptake of allergens and increased colonialization/invasion of bacteria, this results in an (exaggerated) reaction of the immune system and cutaneous inflammation which intensifies barrier impairment. Also in cutaneous wounds, the complete loss of skin barrier function is a tremendous problem because it facilitates invasion of pathogens and dehydration of the wound which promotes the development of chronic wounds.

    The focus of our work is the Tight Junction barrier and its interaction with the other skin barriers. TJs are cell-cell junctions which form a barrier in the stratum granulosum. In addition to interfollicular epidermis, TJs are also found in hair follicles. The loss of the TJ protein Claudin-1 in mice results in death at the first day of birth due to tremendous transepidermal water loss. TJs are composed of a variety of transmembrane proteins (families of claudins, TJ-associated MARVEL-proteins (TAMPs) and junctional adhesion molecules (JAMs)) as well as plaque proteins (e.g. zonula occludens proteins (ZOs), cingulin, MUPP1). We could further show that TJ proteins – besides their role in barrier function – are also involved in differentiation, proliferation, apoptosis and cell-cell adhesion of keratinocytes. These functions are, at least partly, mediated by TJ proteins which are not part of TJ structures, i.e. they are TJ structure-independent.

    TJs interact with the stratum corneum, the immunological barrier, the microbiome, and the chemical barrier.

    In several skin diseases TJs and TJ proteins are altered. These diseases can be classified into diseases with a primary TJ defect, which means the alteration of a TJ protein is causative for the disease, and into diseases with a secondary TJ defect, which means TJ proteins are changed during the course of the disease and contribute to pathogenesis. NISCH (neonatal ichthyosis sclerosing cholangitis)-syndrome which is caused by a loss of the TJ protein Claudin-1 belongs to the first category, psoriasis vulgaris and ichthyosis vulgaris can be categorized into the second one. For atopic dermatitis a genetic correlation with Claudin-1 SNPs was observed in a Northern American cohort, but not in a European cohort. However, TJ proteins are altered secondarily in lesional skin of patients in European cohorts.

    While barrier impairment is negative in skin diseases, it can be desired in certain situations such as topical drug delivery. A better understanding of the TJ barrier and its interaction with the other barriers will help in future to optimize active pharmaceutical ingredients (APIs) and their formulations for better uptake and efficacy. To test the penetration and effect of these APIs and their formulations we developed several model systems: 3D reconstructed human epidermis (RHE) consisting of keratinocytes only, 3D reconstructed human skin (RHS) consisting of keratinocytes and fibroblasts, and ex-vivo skin models (Hamburg model of penetration). These three models can be used complementary. The RHE and RHS have the advantage of being of human origin and easy manipulation, e.g. by siRNA mediated protein knock-down or by using patient cells. Further, they can be investigated at different stages of maturation. However, their skin barrier function is impaired compared to in vivo human skin also when completely maturated, and a correction factor has to be incorporated. The Hamburg model of penetration is of porcine origin, and manipulation e.g. by siRNA treatment is only rarely possible, but its skin barrier function has been shown to be very similar to human skin and penetration can be investigated into different parts of the epidermis and dermis.

    Team

    Katja Bäsler (PhD. student)
    Sophia Bergmann (PhD. student)
    Barbara von Bünau (med. doc. student)
    Pia Houdek (medical technical assistant)
    Katharina Rose (med. doc. student)
    Germar Schüring (M.A., IT)
    Christopher Ueck (PhD. student)
    Ewa Wladykowski (medical technical assistant)
    Michaela Zorn-Kruppa (PostDoc)

    Publications:

    J.M. Brandner, S. Kief, C. Grund, M. Rendl, P. Houdek, C. Kuhn, E. Tschachler, W.W. Franke, I. Moll
    Organization and formation of the tight junction system in human epidermis and cultured keratinocytes
    Eur J Cell Biol, 81 (2002) 253-263

    J.M. Brandner, M. McIntyre, S. Kief, E. Wladykowski, I. Moll
    Expression and localization of tight junction-associated proteins in human hair follicles
    Arch Dermatol Res, 295 (2003) 211-221

    J.M. Brandner, J.D. Schulzke
    Hereditary barrier-related diseases involving the tight junction: lessons from skin and intestine
    Cell Tissue Res, 360 (2015) 723-748

    J.M. Brandner, M. Zorn-Kruppa, T. Yoshida, I. Moll, L.A. Beck, A. De Benedetto
    Epidermal tight junctions in health and disease
    Tissue Barriers, 3 (2015) e974451

    R. Gruber, P.M. Elias, D. Crumrine, T.K. Lin, J.M. Brandner, J.P. Hachem, R.B. Presland, P. Fleckman, A.R. Janecke, A. Sandilands, W.H. McLean, P.O. Fritsch, M. Mildner, E. Tschachler, M. Schmuth
    Filaggrin genotype in ichthyosis vulgaris predicts abnormalities in epidermal structure and function
    Am J Pathol, 178 (2011) 2252-2263

    R. Gruber, C. Bornchen, K. Rose, A. Daubmann, T. Volksdorf, E. Wladykowski, Y.S.S. Vidal, E.M. Peters, M. Danso, J.A. Bouwstra, H.C. Hennies, I. Moll, M. Schmuth, J.M. Brandner
    Diverse Regulation of Claudin-1 and Claudin-4 in Atopic Dermatitis
    Am J Pathol, 185 (2015) 2777-2789

    N. Kirschner, C. Poetzl, P. von den Driesch, E. Wladykowski, I. Moll, M.J. Behne, J.M. Brandner
    Alteration of tight junction proteins is an early event in psoriasis: putative involvement of proinflammatory cytokines
    Am J Pathol, 175 (2009) 1095-1106

    N. Kirschner, C. Bohner, S. Rachow, J.M. Brandner
    Tight junctions: is there a role in dermatology?
    Arch Dermatol Res, 302 (2010) 483-493

    N. Kirschner, P. Houdek, M. Fromm, I. Moll, J.M. Brandner
    Tight junctions form a barrier in human epidermis
    Eur J Cell Biol, 89 (2010) 839-842

    N. Kirschner, M. Haftek, C.M. Niessen, M.J. Behne, M. Furuse, I. Moll, J.M. Brandner
    CD44 regulates tight-junction assembly and barrier function
    J Invest Dermatol, 131 (2011) 932-943

    N. Kirschner, J.M. Brandner
    Barriers and more: functions of tight junction proteins in the skin
    Ann N Y Acad Sci, 1257 (2012) 158-166

    N. Kirschner, R. Rosenthal, D. Gunzel, I. Moll, J.M. Brandner
    Tight junctions and differentiation--a chicken or the egg question?
    Exp Dermatol, 21 (2012) 171-175

    N. Kirschner, R. Rosenthal, M. Furuse, I. Moll, M. Fromm, J.M. Brandner
    Contribution of tight junction proteins to ion, macromolecule, and water barrier in keratinocytes
    J Invest Dermatol, 133 (2013) 1161-1169

    S. Rachow, M. Zorn-Kruppa, U. Ohnemus, N. Kirschner, S. Vidal-y-Sy, P. von den Driesch, C. Bornchen, J. Eberle, M. Mildner, E. Vettorazzi, R. Rosenthal, I. Moll, J.M. Brandner
    Occludin is involved in adhesion, apoptosis, differentiation and Ca2+-homeostasis of human keratinocytes: implications for tumorigenesis
    PLoS One, 8 (2013) e55116

Development of test systems for skin, eye, and mucosa

  • For the investigation of physiological and pathophysiological processes in skin and mucosa we developed the following models which are used for basic research and pharmaceutical testings.

    • Porcine and human ex-vivo wound healing models
    • Porcine ex-vivo infection model
    • Reconstructed human epidermis and skin models
    • Porcine and human ex-vivo penetration models (Hamburg model of penetration)
    • Porcine oral mucos model

    Porcine and human ex-vivo wound healing models

    This model is a patented full thickness wound healing model which is based on porcine or human skin. The model can be used for up to 5-7 days to investigate basic wound healing mechanisms or for the testing of active ingredients, cremes, gels, ointments, formulations, wound dressings or physical wound treatments. It comprises aspects of wound healing phase 1 (inflammatory phase) as well as phase 2 (regeneration phase).

    In recent years we further developed this model to an infected ex-vivo wound healing model (see also services ).

    Publications

    J.M. Brandner, S. Kief, C. Grund, M. Rendl, P. Houdek, C. Kuhn, E. Tschachler, W.W. Franke, I. Moll
    Organization and formation of the tight junction system in human epidermis and cultured keratinocytes
    Eur J Cell Biol, 81 (2002) 253-263

    J.M. Brandner, P. Houdek, B. Husing, C. Kaiser, I. Moll
    Connexins 26, 30, and 43: differences among spontaneous, chronic, and accelerated human wound healing
    J Invest Dermatol, 122 (2004) 1310-1320

    J.M. Brandner, P. Houdek, T. Quitschau, U. Siemann-Harms, U. Ohnemus, I. Willhardt, I. Moll
    An ex-vivo model to evaluate dressings and drugs for wound healing.
    EWMA J, 6 (2006) 11-15

    J.M. Brandner, S. Zacheja, P. Houdek, I. Moll, R. Lobmann
    Expression of matrix metalloproteinases, cytokines, and connexins in diabetic and nondiabetic human keratinocytes before and after transplantation into an ex vivo wound-healing model
    Diabetes Care, 31 (2008) 114-120

    I. Moll, P. Houdek, Schmidt H, Moll R
    Characterization of epidermal wound healing in a human skin organ culture model: Acceleration by transplanted keratinocytes
    J Invest Dermatol, 111 (1998) 251-258

    A. Neub, P. Houdek, U. Ohnemus, I. Moll, J.M. Brandner
    Biphasic regulation of AP-1 subunits during human epidermal wound healing
    J Invest Dermatol, 127 (2007) 2453-2462

    C.S. Wright, S. Pollok, D.J. Flint, J.M. Brandner, P.E. Martin
    The connexin mimetic peptide Gap27 increases human dermal fibroblast migration in hyperglycemic and hyperinsulinemic conditions in vitro
    J Cell Physiol, 227 (2012) 77-87

    M. Vockel, S. Pollok, U. Breitenbach, I. Ridderbusch, H.J. Kreienkamp, J.M. Brandner
    Somatostatin inhibits cell migration and reduces cell counts of human keratinocytes and delays epidermal wound healing in an ex vivo wound model
    PLoS One, 6 (2011) e19740

    S. Ebeling, K. Naumann, S. Pollok, T. Wardecki, Y.S.S. Vidal, J.M. Nascimento, M. Boerries, G. Schmidt, J.M. Brandner, I. Merfort
    From a traditional medicinal plant to a rational drug: understanding the clinically proven wound healing efficacy of birch bark extract
    PLoS One, 9 (2014) e86147

    M. Zubair, H. Nybom, C. Lindholm, J.M. Brandner, K. Rumpunen
    Promotion of wound healing by Plantago major L. leaf extracts - ex-vivo experiments confirm experiences from traditional medicine
    Nat Prod Res, (2015) 1-3

    Porcine ex-vivo infection model

    This is a full thickness skin model that is infected with Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, or Candida albicans respectively. We use this model to elucidate the interaction of bacteria/fungi with the various components of the skin barrier, especially tight junctions. Further, the model can be used for testings concerning the antimicrobial /antifungal efficacy of substances and dressings (see also lab services ) in a context which does not only take the interaction of bacteria and the substances/dressings into account, but which also regards the interaction of both with the skin. This research is performed in collaboration with Prof. Holger Rohde (Department of Medical Microbiology, Virology and Hygiene). Recently, we used this model in non-infected form to investigate the effect of snake venoms on the skin.

    Publications

    M. Molander, D. Staerk, H. Morck Nielsen, J.M. Brandner, D. Diallo, C. Kusamba Zacharie, J. van Staden, A.K. Jager
    Investigation of skin permeation, ex vivo inhibition of venom-induced tissue destruction, and wound healing of African plants used against snakebites
    J Ethnopharmacol, 165 (2015) 1-8

    U. Ohnemus, K. Kohrmeyer, P. Houdek, H. Rohde, E. Wladykowski, S. Vidal, M.A. Horstkotte, M. Aepfelbacher, N. Kirschner, M. J. Behne, I. Moll, J. M. Brandner
    Regulation of epidermal tight-junctions (TJ) during infection with exfoliative toxin-negative Staphylococcus strains.
    J Invest Dermatol 128 (2008) 906-916

    Reconstructed human epidermis and skin

    Reconstructed human epidermis (RHE) consists of primary keratinocytes, reconstructed human skin (RHS) of fibroblasts seeded into a collagen matrix and overlaying keratinocytes. Both form due to special cultivation protocols (air-liquid interface, differentiating culture medium) a stratified epidermis with functional stratum corneum and tight junctions.

    Reconstructed human epidermis and reconstructed human skin can be investigated immunohistologically, biochemically, molecular biologically and functionally. They can be manipulated e.g. by knock-down of certain proteins or by the utilization of patient cells.

    Publications

    J.M. Brandner, S. Kief, C. Grund, M. Rendl, P. Houdek, C. Kuhn, E. Tschachler, W.W. Franke, I. Moll
    Organization and formation of the tight junction system in human epidermis and cultured keratinocytes
    Eur J Cell Biol, 81 (2002) 253-263.

    R. Gruber, C. Börnchen, K. Rose, A. Daubmann, T. Volksdorf, E. Wladykowski, S. Vidal-y-Sy, E. M. Peters, M. Danso, J. A. Bouwstra, H. C. Hennies, I. Moll, M. Schmuth, J. M. Brandner,
    Diverse Regulation of Claudin-1 and Claudin-4 in Atopic Dermatitis.
    Am J Pathol, 185 (2015) 2777-2789

    S. Rachow, M. Zorn-Kruppa, U. Ohnemus, N. Kirschner, S. Vidal-y-Sy, P. von den Driesch, C. Bornchen, J. Eberle, M. Mildner, E. Vettorazzi, R. Rosenthal, I. Moll, J.M. Brandner
    Occludin is involved in adhesion, apoptosis, differentiation and Ca2+-homeostasis of human keratinocytes: implications for tumorigenesis
    PLoS One, 8 (2013) e55116

    Porcine and human ex-vivo penetration models (Hamburg model of penetration)

    These either porcine or human full thickness models allow the investigation of penetration of substances (e.g. in different formulations) into different layers of the skin. We have shown that these models are viable and metabolically active, and they exhibit normal differentiation, tight junction barrier function and proliferation. Further, we demonstrated that human and porcine skin show similar penetration rates.

    Publications

    M.E. Herbig, P. Houdek, S. Gorissen, M. Zorn-Kruppa, E. Wladykowski, T. Volksdorf, S. Grzybowski, G. Kolios, C. Willers, H. Mallwitz, I. Moll, J.M. Brandner
    A custom tailored model to investigate skin penetration in porcine skin and its comparison with human skin
    Eur J Pharm Biopharm, 95 (2015) 99-109.

    Infected porcine oral mucosa model

    In this model, which is based on porcine oral mucosa, we investigate the efficacy of various antifungal drugs, antiseptics and washing lotions concerning the reduction of bacterial/fungal load, and also concerning the viability, differentiation, proliferation and barrier function of the mucosa.

    Publications

    U. Ohnemus, C. Willers, M. Bubenheim, M. A. Horstkotte, P. Houdek, F. Fischer, P. Schmage, I. Moll, J. M. Brandner
    An ex-vivo oral mucosa infection model for the evaluation of the topical activity of antifungal agents. Mycoses 51 (2008) 21-29

    Team

    Pia Houdek (medical technical assistant)
    Germar Schüring (assistant)

New active ingredients, formulations and physical therapy options have to be tested preclinically concerning their efficacy and safety in appropriate test systems. Also optimization of formulations has to be performed in test systems, preferably without animal experiments. Moreover, due to REACH (European regulation for Registration, Evaluation, Authorization, and Restriction of Chemicals), the number of safety and toxicology testings which can not be performed in animal experiments is largely expanding. We develop test systems for skin, eye and mucosa.

Some of these test systems are provided as services to companies and institutes.

  • Hemicornea model:
    This is a threedimensional (3D) artificial cornea model which is bioengineered by using immortalized human cell lines. The model consists of corneal fibroblasts seeded into a collageneous stromagel, which is subsequently overlayed by a multilayered epithelium of corneal epithelial cells. Based on this hemicornea model several test methods have been established to evaluate permeability and toxicity of substances.

    Publications

    M. Hahne, M. Zorn-Kruppa, G. Guzman, J.M. Brandner, E. Haltner-Ukomado, H. Watzig, S. Reichl
    Prevalidation of a human cornea construct as an alternative to animal corneas for in vitro drug absorption studies
    J Pharm Sci, 101 (2012) 2976-2988

    R. Tandon, M. Bartok, M. Zorn-Kruppa, J.M. Brandner, D. Gabel, M. Engelke
    Assessment of the eye irritation potential of chemicals: A comparison study between two test methods based on human 3D hemi-cornea models
    Toxicol In Vitro, (2015)

    M. Zorn-Kruppa, S. Tykhonova, G. Belge, J. Bednarz, H.A. Diehl, M. Engelke
    A human corneal equivalent constructed from SV40-immortalised corneal cell lines
    Altern Lab Anim, 33 (2005) 37-45

    M. Zorn-Kruppa, P. Houdek, E. Wladykowski, M. Engelke, M. Bartok, K.R. Mewes, I. Moll, J.M. Brandner
    Determining the Depth of Injury in Bioengineered Tissue Models of Cornea and Conjunctiva for the Prediction of All Three Ocular GHS Categories
    PLoS One, 9 (2014) e114181

Molecular Andrology

  • The true identity of human spermatogonial stem cells (hSSCs) could not be uncovered to date. On the other hand, therapeutical application of this cell type may be useful.

    By microarray analysis, we identified the Fibroblast growth factor receptor 3 (FGFR3) as a human spermatogonial specific marker. FGFR3 is expressed on the cell surface of A type spermatogonia (SPG). Immunofluorescent multiple staining followed by confocal microscopy demonstrated the appearance of the protein only within non-proliferating and non-differentiating SPG and the coexpression with the pluripotency marker UTF1. Additionally, FGFR3 protein is only expressed in small spermatogonial clusters, as revealed by whole mount preparations of seminiferous tubules. Hence, a potential stem cell state of the FGFR3+ human SPG is indicated.

    In our current project, we want to optimize culture conditions for by magnetic beads isolated FGFR3+ SPG to propagate the potential hSSCs in their undifferentiated state via self renewal. Therefore, we want to utilize established protocols for hSSC proliferation and own approaches with growth factors in different combinations and concentrations. Cellular expansion of the potential hSSCs should serve as a prerequisite for xenotransplantation which is the only approach to reveal hSSC characteristics. Analysis of the epigenetic state and marker expression of pre- and post-cultivated cells should identify and therefore exclude any cellular changes during cell culture.

    The new findings are anticipated to gain knowledge about the mechanism of human spermatogenesis and may have implications for a therapeutical approach with hSSCs.

    Team

    Beate Roth (medical technical assistant)

    Dr. Andrea Salzbrunn (physician)

    Dr. Domenica Varwig-Janßen (physician)

  • In our research group we are investigating the gene expression (the turning on and off of genes) during spermatogenesis (maturation of germ cells) in the testis and in spermatozoa (sperm cells) of the male.
    Many men have a so-called “idiopathic infertility”, which means that the causes of their impaired spermatogenesis, which leads to a decreased sperm number in their ejaculates (semen), are largely unknown. We aim to uncover the mechanisms that have a negative influence on the differentiation of germ cells in the testis. However, some men present with a completely normal ejaculate, and although the female partner is inconspicuous at the gynecological level, pregnancy is not achieved within a considerate time.
    We investigate, if these men have molecular disorders in their sperm cells that are not evident in a normal spermiogram (analysis of semen quality) and that may exert a negative effect on the sperm-oocyte interaction.

    Team

    Dr. Heike Cappallo-Obermann (PostDoc)
    Beate Roth (medical technical assistant)
    Dr. Andrea Salzbrunn (physician)
    Dr. Varwig-Janßen (physician)

Tumor biology

Skin tumors are of high interest because they are frequent (e.g. incidence of basal cell carcinoma 100/100,000/year) or highly aggressive (malignant melanoma, Merkel cell carcinoma).
We investigate several different skin tumors in basic and clinical research. In addition, we are engaged in the context of our infertility clinic with testis cancer.

Basic research

  • Malignant melanoma is the skin tumor with highest risk to metastasize. It is responsible for more than 90% of all deaths due to skin tumors. In 2008, 17,800 new melanoma cases were diagnosed and 2500 patients died from melanoma in Germany. Fair-skinned persons (skin type I and II) have a higher incidence to develop malignant melanoma than persons with skin type III and IV.

    Malignant melanoma has to be distinguished from benign skin tumors, e.g. dysplastic nevi. This is done clinically as well as (immuno)-histochemically, but can be challenging in ambiguous cases.

    Therapy depends on tumor stage and mutation status of the tumor and can include tumor excision, radiotherapy, adjuvant interferon therapy, signal transduction inhibitor therapy (BRAF, c-KIT), immunotherapy (Ipilimumab) as well as mono- and poly-chemotherapies. Especially in stage IV satisfying long term therapies are still missing. Thus, development/validation of new therapies but also prevention of tumorigenesis and progression are important aims of our research.

    We are interested in the role of cell-cell and cell-matrix adhesion molecules as well as additional marker molecules in development and progression of malignant melanoma. One of our strategies is to establish cell cultures from tumors, manipulate them and investigate them concerning tumor growth and the formation of metastasis in SCID mice (collaboration with Prof. Schumacher institute of Anatomy and Experimental Morphology ). Further, in vitro investigation of metastasis is performed in 2D and 3D tumor invasion models.

    Of special interest is also the identification of new markers to distinguish melanoma from benign skin tumors, especially in ambiguous cases, and the investigation of alterations of cell-adhesion molecules in the tumor microenvironment and its contribution to tumor progression.

    Team

    Lina Hildebrandt (physician)
    Pia Houdek (medical technical assistant)
    Mutiha Pandjaitan (PhD student)
    Dr. Andrea Ramirez-Vanegas (physician)
    Dominik Schoch (physician)
    Sabine Vidal-y-Sy (medical technical assistant)
    Ewa Wladykowski (medical technical assistant)

    Publications

    J.M. Brandner, M. Zorn-Kruppa, T. Yoshida, I. Moll, L.A. Beck, A.
    De Benedetto, Epidermal tight junctions in health and disease
    Tissue Barriers, 3 (2015) e974451

    J.M. Brandner, N.K. Haass
    Melanoma's connections to the tumour microenvironment
    Pathology, 45 (2013) 443-452

    N.K. Haass, E. Wladykowski, S. Kief, I. Moll, J.M. Brandner
    Differential induction of connexins 26 and 30 in skin tumors and their adjacent epidermis
    J Histochem Cytochem, 54 (2006) 171-182

    N.K. Haass, D. Ripperger, E. Wladykowski, P. Dawson, P.A. Gimotty, C. Blome, F. Fischer, P. Schmage, I. Moll, J.M. Brandner
    Melanoma progression exhibits a significant impact on connexin expression patterns in the epidermal tumor microenvironment
    Histochem Cell Biol, 133 (2010) 113-124

    D.R. Menon, C. Wels, E. Bonyadi Rad, S. Joshi, H. Knausz, J. Lade-Keller, J.M. Brandner, H. Schaider
    TGF-beta1 and TNF-alpha differentially regulate Twist1 mediated resistance towards BRAF/MEK inhibition in melanoma
    Pigment Cell Melanoma Res, 26 (2013) 912-916

    S. Meyer, T.J. Fuchs, A.K. Bosserhoff, F. Hofstadter, A. Pauer, V. Roth, J.M. Buhmann, I. Moll, N. Anagnostou, J.M. Brandner, K. Ikenberg, H. Moch, M. Landthaler, T. Vogt, P.J. Wild
    A seven-marker signature and clinical outcome in malignant melanoma: a large-scale tissue-microarray study with two independent patient cohorts
    PLoS One, 7 (2012) e38222

    S. Rachow, M. Zorn-Kruppa, U. Ohnemus, N. Kirschner, S. Vidal-y-Sy, P. von den Driesch, C. Bornchen, J. Eberle, M. Mildner, E. Vettorazzi, R. Rosenthal, I. Moll, J.M. Brandner
    Occludin is involved in adhesion, apoptosis, differentiation and Ca2+-homeostasis of human keratinocytes: implications for tumorigenesis
    PLoS One, 8 (2013) e55116

    S. Rickelt, W.W. Franke, Y. Doerflinger, S. Goerdt, J.M. Brandner, W.K. Peitsch
    Subtypes of melanocytes and melanoma cells distinguished by their intercellular contacts: heterotypic adherens junctions, adhesive associations, and dispersed desmoglein 2 glycoproteins
    Cell Tissue Res, 334 (2008) 401-422

    K.S. Smalley, P. Brafford, N.K. Haass, J.M. Brandner, E. Brown, M. Herlyn
    Up-regulated expression of zonula occludens protein-1 in human melanoma associates with N-cadherin and contributes to invasion and adhesion
    Am J Pathol, 166 (2005) 1541-1554

    P. Meister, I. Moll,
    Report of the Working Group on Dermatopathology at the 97th annual meeting of the DGP in Heidelberg
    Pathologe, 34 Suppl 2 (2013) 282-283

    C. Wessel, C.C. Westhoff, K. Nowak, I. Moll, P.J. Barth
    CD34(+) fibrocytes in melanocytic nevi and malignant melanomas of the skin
    Virchows Arch, 453 (2008) 485-489

    A. Thies, A. Berlin, G. Brunner, H.J. Schulze, I. Moll, U. Pfuller, C. Wagener, M. Schachner, P. Altevogt, U. Schumacher
    Glycoconjugate profiling of primary melanoma and its sentinel node and distant metastases: implications for diagnosis and pathophysiology of metastases
    Cancer Lett, 248 (2007) 68-80

    A. Thies, M. Schachner, J. Berger, I. Moll, H.J. Schulze, G. Brunner, U. Schumacher
    The developmentally regulated neural crest-associated glycotope HNK-1 predicts metastasis in cutaneous malignant melanoma
    The Journal of pathology, 203 (2004) 933-939

    C. Freudlsperger, I. Moll, U. Schumacher, A. Thies
    Anti-proliferative effect of peroxisome proliferator-activated receptor gamma agonists on human malignant melanoma cells in vitro
    Anticancer Drugs, 17 (2006) 325-332

  • Squamous cell carcinoma of the skin is a malignant tumor often growing with local destructions. However, it has only a small risk to metastasize (5%). It evolves often from non-malignant precursors and carcinoma in situ (e.g. actinic keratosis, Morbus Bowen). In addition, it can develop from chronically inflamed skin, e.g. chronic wounds, chronic inflammatory skin diseases and chronic radiodermatitis.

    Chronic UV exposure is the most important etiological factor for the development of squamous cell carcinoma. In addition, carcinogenic substances, ironizing radiation, HPV, immunosuppression and genetic predisposition can play a role.

    We are primarily interested in the processes leading from UV damaged skin to carcinoma in situ and squamous cell carcinoma and focus on cell-cell and cell-matrix adhesion molecules.

    Team

    Lina Hildebrandt (physician)
    Dominik Schoch (physician)
    Sabine Vidal-y-Sy (medical technical assistant)
    Ewa Wladykowski (medical technical assistant)


    Publications

    J.M. Brandner, M. Zorn-Kruppa, T. Yoshida, I. Moll, L.A. Beck, A. De Benedetto
    Epidermal tight junctions in health and disease
    Tissue Barriers, 3 (2015) e974451

    P. Meister, I. Moll
    Report of the Working Group on Dermatopathology at the 97th annual meeting of the DGP in Heidelberg
    Pathologe, 34 Suppl 2 (2013) 282-283

    M. Oldenburg, B. Kuechmeister, U. Ohnemus, X. Baur, I. Moll
    Extrinsic skin ageing symptoms in seafarers subject to high work-related exposure to UV radiation
    Eur J Dermatol, 23 (2013) 663-670

    M. Oldenburg, B. Kuechmeister, U. Ohnemus, X. Baur, I. Moll
    Actinic keratosis among seafarers
    Arch Dermatol Res, 305 (2013) 787-796

    S. Rachow, M. Zorn-Kruppa, U. Ohnemus, N. Kirschner, S. Vidal-y-Sy, P. von den Driesch, C. Bornchen, J. Eberle, M. Mildner, E. Vettorazzi, R. Rosenthal, I. Moll, J.M. Brandner
    Occludin is involved in adhesion, apoptosis, differentiation and Ca2+-homeostasis of human keratinocytes: implications for tumorigenesis
    PLoS One, 8 (2013) e55116

    I. Kurokawa, K. Takahashi, I. Moll, R. Moll
    Expression of keratins in cutaneous epithelial tumors and related disorders--distribution and clinical significance
    Exp Dermatol, 20 (2011) 217-228

    H. Schluter, I. Moll, H. Wolburg, W.W. Franke
    The different structures containing tight junction proteins in epidermal and other stratified epithelial cells, including squamous cell metaplasia
    Eur J Cell Biol, 86 (2007) 645-655

    N.K. Haass, E. Wladykowski, S. Kief, I. Moll, J.M. Brandner
    Differential induction of connexins 26 and 30 in skin tumors and their adjacent epidermis
    J Histochem Cytochem, 54 (2006) 171-182

  • Merkel cell carcinoma (MCC) is a very aggressive neuroendocrine skin carcinoma. Its tumor specific 5 year survival rate is 60%. MCC is rare, but its incidence increased threefold during the last years, being now 0.3/100,000/year in fair-skinned European and American populations. MCC is mainly a tumor of the elderly (mean age ca. 70 years) and immunosuppressed persons. Localization is frequently at the head and neck area and the extremities, rarely at the trunk. Clinically, bluish-red tumors which grow rapidly can be seen. MCC tend to relapse in loco and metastasize in different organs in the course of the first two years. In approximately 80% of the tumors a newly described polyomavirus (Merkel cell polyomavirus) is responsible for tumorigenesis. Therapeutical options are excision, irraditation of the tumor and local lymph nodes as well has chemotherapies, which are, however, often only temporary successful. Thus, new therapeutic options are urgently needed.

    We establish Merkel cell carcinoma cultures from tumor tissue in collaboration with the Dermatology Departments of the Universities of Erlangen and Frankfurt. The so-derived cell lines are characterized cell biologically and can be used for a variety of research approaches. In collaboration with Prof. Schumacher (Institute for Anatomy and Experimental Morphology) we investigate growth and formation of metastasis of these cells in SCID mice. In collaboration with Prof. Fischer (Department of Medical Microbiology, Virology and Hygiene) we perform investigations concerning the expression of the virus and its correlation to histological and clinical tumor parameters in vivo and in vitro. Finally, we investigate in collaboration with Prof. Pantel (Institute for tumor biology) single circulating tumor cells in peripheral blood.

    Team

    Lina Hildebrandt (physician)
    Pia Houdek (medical technical assistant)
    Dr. Felix Koester (physician)
    Sabine Vidal-y-Sy (medical technical assistant)
    Ewa Wladykowski (medical technical assistant)


    Publications

    M. Leitz, K. Stieler, A. Grundhoff, I. Moll, J.M. Brandner, N. Fischer
    Merkel cell polyomavirus detection in Merkel cell cancer tumors in Northern Germany using PCR and protein expression
    J Med Virol, 86 (2014) 1813-1819

    T. Tilling, E. Wladykowski, A.V. Failla, P. Houdek, J.M. Brandner, I. Moll
    Immunohistochemical analyses point to epidermal origin of human Merkel cells
    Histochem Cell Biol, 141 (2014) 407-421

    T. Tilling, I. Moll
    Which are the cells of origin in merkel cell carcinoma?
    J Skin Cancer, 2012 (2012) 680410

    S. Rickelt, I. Moll, W.W. Franke
    Intercellular adhering junctions with an asymmetric molecular composition: desmosomes connecting Merkel cells and keratinocytes
    Cell Tissue Res, 346 (2011) 65-77

    N. Fischer, J. Brandner, F. Fuchs, I. Moll, A. Grundhoff
    Detection of Merkel cell polyomavirus (MCPyV) in Merkel cell carcinoma cell lines: cell morphology and growth phenotype do not reflect presence of the virus
    Int J Cancer, 126 (2010) 2133-2142

    A.C. Eispert, F. Fuchs, J.M. Brandner, P. Houdek, E. Wladykowski, I. Moll
    Evidence for distinct populations of human Merkel cells
    Histochem Cell Biol, 132 (2009) 83-93

    J. Becker, C. Mauch, R.D. Kortmann, U. Keilholz, F. Bootz, C. Garbe, A. Hauschild, I. Moll
    Short German guidelines: Merkel cell carcinoma
    J Dtsch Dermatol Ges, 6 Suppl 1 (2008) S15-16

    I. Moll
    Merkel cell carcinoma--clinical presentation and treatment
    Front Radiat Ther Oncol, 39 (2006) 68-74

  • Infertile men have an increased risk of developing germ cell cancer of the testis; this is specifically true for those showing primary impairment of spermatogenesis. At present approximately 20% of testis cancer patients are diagnosed during physical examination in preparation of a treatment for male infertility. Intratubular germ cell neoplasia (IGCNU) is the precursor lesion of testicular germ cell tumours which is also referred to as carcinoma in situ (CIS) or testicular intraepithelial neo­plasia (TIN). The precursor lesion is often present many years before the manifestation of an open tumour emphasizing its great significance for early detection of testis cancer.

    Presently, testicular germ cell cancer and its precursor lesion IGCNU are diagnosed in testicular biopsies by histological and/or immmunohistochemical methods. Reliable markers for cancer cell detection are known and validated for long; the Oct3/4 transcription factor is specifically well suited as a robust nuclear marker of germ cell tumours. Our project aims at the development of improved diagnostic methods for patients attending consultation at an infertility clinic to safely and fast exclude IGCNU. Moreover, we are studying a novel nuclear structure specifically occurring in IGCNU to learn more about the development and progression of testis cancer. The focus of this study is on the nuclear envelope. A highly regulated barrier which mediates contact between the nucleus and the cytoplasm in eukaryotic cells, the nuclear envelope has been implicated in dynamic chromosome positioning and cytoskeletal interaction as well as chromatin organization and gene regulation. Its structure and composition in tumour cells differs from that of the corresponding normal cell type.

    Team

    Beate Roth (medical technical assistant)
    Dr. Andrea Salzbrunn (physician)
    Dr. Domenica Varwig-Janßen (physician)
    Ewa Wladykowski (medical technician assistent)

Clinical Research

  • We perform clinical studies in collaboration with the UCCH concerning the following tumor entities:

    • Basal cell carcinoma
    • Malignant melanoma
    • Merkelcell carcinoma

    Team

    Lina Hildebrandt (physician)
    Dr. Felix Koester (phycician)
    Susanne Pohl (study nurse)
    Dominik Schoch (physician)

Wound healing

In our working groups we are interested in basic mechanisms of wound healing but also in the development and validation of new therapies, e.g. with transplanted keratinocytes or natural plant products.

Basic Research

  • Wound healing is a complex process consisting of three major, partly overlapping phases:

    1. Inflammatory phase (defense!)
    2. Regeneration phase (tissue growth!)
    3. Remodelling phase (scar formation!)

    The first phase results in coagulation, cleaning of the wound, formation of a provisional matrix and promotion of wound regeneration. This is achieved by the activation of platelets and coagulation factors, migration of macrophages, neutrophils and other immune cells into the wound site and release of reactive oxygen species, proinflammatory cytokines and growth factors.

    In the second phase, epidermis and dermis regenerate by proliferation and migration of keratinocytes and fibroblasts, the formation of new blood vessels and the generation of extracellular matrix. During this phase the wound is repelnished with granulation tissue and closed by a new epithelium.

    The third phase is important for the further restoration of functionality of the skin (barrier function, tensile strength, sensitivity). It is characterized by a remodeling of extracellular matrix, reduction of myofibroblasts and blood vessels by apoptosis as well as atrophy of the hypertrophic epidermis. Tyically this remodeling results in a more or less pronounced scar.

    Disturbance of these well-orchestrated phases can lead to chronic wounds. Causes for chronic wounds are venous or arterial diseases (e.g. venous leg ulcers), metabolic diseases such as diabetes mellitus (diabetic foot syndrome), ongoing pressure (decubitus ulcers) and immunological diseases (e.g. pyoderma gangrenosum). Further, infections can cause or aggravate chronic wounds.

    Tight Junctions (TJs) are barrier-forming cell-cell junctions. In addition, TJ proteins are involved in cell proliferation, differentiation, cell-cell adhesion and apoptosis. During wound healing, TJ proteins are re-expressed very early in the regenerating epidermis. We investigate the role of TJ proteins in acute and chronic wounds in normal as well as diabetic skin.

    Gap junctions are channel forming cell-cell junctions which mediate direct cell-cell communication. They allow the controlled exchange of ions, second messenger molecules and metabolites with a molecular weight of up to 1000 Da. Gap junctions are formed by connexins, a family of transmembrane proteins. We and others could show that gap junctions / connexins play an important role in wound healing. They are involved in migration, proliferation, differentiation and apoptosis as well as cytokine release. Of note, diabetic origin shows an influence on connexins and their susceptibility to external manipulation. In our present work we investigate the interplay of connexins with other cell junctions and signals influencing gap junctions during wound healing.

    Team

    Pia Houdek (medical technical assistant)
    Dr. Carmen Klingelhöller (phycisian)
    Kathrin Schawjinsik (med. doc. student)
    Christopher Ueck (PhD. student)
    Sabine Vidal-y-Sy (medical technical assistant)
    Thomas Volksdorf (PhD. student)
    Ewa Wladykowski (medical technical assistant)

    Publications

    J.M. Brandner, P. Houdek, B. Husing, C. Kaiser, I. Moll
    Connexins 26, 30, and 43: differences among spontaneous, chronic, and accelerated human wound healing
    J Invest Dermatol, 122 (2004) 1310-1320

    J.M. Brandner, S. Zacheja, P. Houdek, I. Moll, R. Lobmann
    Expression of matrix metalloproteinases, cytokines, and connexins in diabetic and nondiabetic human keratinocytes before and after transplantation into an ex vivo wound-healing model
    Diabetes Care, 31 (2008) 114-120

    J.M. Brandner, J.D. Schulzke
    Hereditary barrier-related diseases involving the tight junction: lessons from skin and intestine
    Cell Tissue Res, 360 (2015) 723-748

    J.M. Brandner, M. Zorn-Kruppa, T. Yoshida, I. Moll, L.A. Beck, A. De Benedetto
    Epidermal tight junctions in health and disease
    Tissue Barriers, 3 (2015) e974451

    N. Kirschner, M. Haftek, C.M. Niessen, M.J. Behne, M. Furuse, I. Moll, J.M. Brandner
    CD44 regulates tight-junction assembly and barrier function
    J Invest Dermatol, 131 (2011) 932-943

    N. Kirschner, R. Rosenthal, D. Gunzel, I. Moll, J.M. Brandner
    Tight junctions and differentiation--a chicken or the egg question?
    Exp Dermatol, 21 (2012) 171-175

    N. Kirschner, R. Rosenthal, M. Furuse, I. Moll, M. Fromm, J.M. Brandner
    Contribution of tight junction proteins to ion, macromolecule, and water barrier in keratinocytes
    J Invest Dermatol, 133 (2013) 1161-1169

    A. Neub, P. Houdek, U. Ohnemus, I. Moll, J.M. Brandner
    Biphasic regulation of AP-1 subunits during human epidermal wound healing
    J Invest Dermatol, 127 (2007) 2453-2462

    S. Pollok, A.C. Pfeiffer, R. Lobmann, C.S. Wright, I. Moll, P.E. Martin, J.M. Brandner
    Connexin 43 mimetic peptide Gap27 reveals potential differences in the role of Cx43 in wound repair between diabetic and non-diabetic cells
    J Cell Mol Med, 15 (2011) 861-873

    S. Rachow, M. Zorn-Kruppa, U. Ohnemus, N. Kirschner, S. Vidal-y-Sy, P. von den Driesch, C. Bornchen, J. Eberle, M. Mildner, E. Vettorazzi, R. Rosenthal, I. Moll, J.M. Brandner
    Occludin is involved in adhesion, apoptosis, differentiation and Ca2+-homeostasis of human keratinocytes: implications for tumorigenesis
    PLoS One, 8 (2013) e55116

    C.S. Wright, S. Pollok, D.J. Flint, J.M. Brandner, P.E. Martin
    The connexin mimetic peptide Gap27 increases human dermal fibroblast migration in hyperglycemic and hyperinsulinemic conditions in vitro
    J Cell Physiol, 227 (2012) 77-87


  • Estrogens positively influence wound healing in general, and estrogen substitution improves wound healing in post menopausal wounds. We investigate the effect of estrogens on male and female wounds in combination with other therapies in ex vivo wound healing models.

    Team

    Pia Houdek (medical technical assistant)
    Kathrin Schawjinski (med. doc. student)
    Ewa Wladykowski (medical technical assistant)

Applied Science

  • We are interested in the elucidation of the wound healing potential of natural products and the underlying mechanisms. For example, we could prove in a collaboration project with the Universitiy of Tübingen, the University of Freiburg and the Birken AG that an extract from birch bark has a positive effect on wound healing and reveal the underlying mechanisms. These investigations accompanied the process of drug development from the first preclinical investigations to clinical studies.

    In another project, the positive effect of plantago major, a plant used in traditional medicine of several countries could be shown.

    Finally, we investigate in collaboration with the HanseMerkurZentrum for traditional chinese medicine the effect of traditionals chinese herbs on wound healing. For one of these projects, Prof. Brandner was awarded the Bionorica Global Research Award 2013/14

    Team

    Pia Houdek (medical technical assistant)
    Janine Radtke (PhD student)
    Christopher Ueck (PhD student)

    Publications

    S. Ebeling, K. Naumann, S. Pollok, T. Wardecki, Y.S.S. Vidal, J.M. Nascimento, M. Boerries, G. Schmidt, J.M. Brandner, I. Merfort
    From a traditional medicinal plant to a rational drug: understanding the clinically proven wound healing efficacy of birch bark extract
    PLoS One, 9 (2014) e86147

    H.R. Metelmann, J. Brandner, H. Schumann, F. Bross, M. Hoffmann, F. Podmelle
    Accelerating the aesthetic benefit of wound healing by triterpene
    J Craniomaxillofac Surg, 40 (2012) e150-154

    H.R. Metelmann, J.M. Brandner, H. Schumann, F. Bross, R. Fimmers, K. Bottger, A. Scheffler, F. Podmelle
    Accelerated reepithelialization by triterpenes: proof of concept in the healing of surgical skin lesions
    Skin Pharmacol Physiol, 28 (2015) 1-11

    Steinbrenner et al - submitted

    M. Zubair, H. Nybom, C. Lindholm, J.M. Brandner, K. Rumpunen
    Promotion of wound healing by Plantago major L. leaf extracts - ex-vivo experiments confirm experiences from traditional medicine
    Nat Prod Res, (2015) 1-3