Yuval Ramot

Reversal of Alopecia Areata Following Treatment With the JAK1/2 Inhibitor Baricitinib.

Background Alopecia areata (AA) is an autoimmune disease resulting in hair loss with devastating psychosocial consequences. Despite its high prevalence, there are no FDA-approved treatments for AA. Prior studies have identified a prominent interferon signature in AA, which signals through JAK molecules. Methods A patient with AA was enrolled in a clinical trial to examine the efficacy of baricitinib, a JAK1/2 inhibitor, to treat concomitant CANDLE syndrome. In vivo, preclinical studies were conducted using the C3H/HeJ AA mouse model to assess the mechanism of clinical improvement by baricitinib. Findings The patient exhibited a striking improvement of his AA on baricitinib over several months. In vivo studies using the C3H/HeJ mouse model demonstrated a strong correlation between resolution of the interferon signature and clinical improvement during baricitinib treatment. Interpretation Baricitinib may be an effective treatment for AA and warrants further investigation in clinical trials.

A randomized, double-blind, placebo- and active-controlled, half-head study to evaluate the effects of platelet-rich plasma on alopecia areata

Alopecia areata (AA) is a common autoimmune condition, causing inflammation‐induced hair loss. This disease has very limited treatment possibilities, and no treatment is either curative or preventive. Platelet‐rich plasma (PRP) has emerged as a new treatment modality in dermatology, and preliminary evidence has suggested that it might have a beneficial role in hair growth.

Thyroid-stimulating hormone, a novel, locally produced modulator of human epidermal functions, is regulated by thyrotropin-releasing hormone and thyroid hormones

Several elements of the hypothalamic-pituitary-thyroid axis (HPT) reportedly are transcribed by human skin cell populations, and human hair follicles express functional receptors for TSH. Therefore, we asked whether the epidermis of normal human skin is yet another extrathyroidal target of TSH and whether epidermis even produces TSH. If so, we wanted to clarify whether intraepidermal TSH expression is regulated by TRH and/or thyroid hormones and whether TSH alters selected functions of normal human epidermis in situ. TSH and TSH receptor (TSH-R) expression were analyzed in the epidermis of normal human scalp skin by immunohistochemistry and PCR. In addition, full-thickness scalp skin was organ cultured and treated with TSH, TRH, or thyroid hormones, and the effect of TSH treatment on the expression of selected genes was measured by quantitative PCR and/or quantitative immunohistochemistry. Here we show that normal human epidermis expresses TSH at the mRNA and protein levels in situ and transcribes TSH-R. It also contains thyrostimulin transcripts. Intraepidermal TSH immunoreactivity is up-regulated by TRH and down-regulated by thyroid hormones. Although TSH-R immunoreactivity in situ could not be documented within the epidermis, but in the immediately adjacent dermis, TSH treatment of organ-cultured human skin strongly up-regulated epidermal expression of involucrin, loricrin, and keratins 5 and 14. Thus, normal human epidermis in situ is both an extrapituitary source and (possibly an indirect) target of TSH signaling, which regulates defined epidermal parameters. Intraepidermal TSH expression appears to be regulated by the classical endocrine controls that determine the systemic HPT axis.

Biocompatibility and safety of PLA and its copolymers

PLA and its copolymers are commonly used for a wide variety of applications. While they are considered to be biocompatible, side effects resulting from their implantation have been reported. The implantation of biomaterials always results in a foreign body reaction. Such a reaction has also been reported following PLA and its copolymers. This article reviews the process of inflammatory reaction that is to be expected following implantation of PLA, and it highlights specific cases in which the inflammatory reaction can result in safety concerns. The authors also review selected cases from different medical fields to demonstrate possible clinical side effects resulting from its use.

What causes alopecia areata

The pathobiology of alopecia areata (AA), one of the most frequent autoimmune diseases and a major unsolved clinical problem, has intrigued dermatologists, hair biologists and immunologists for decades. Simultaneously, both affected patients and the physicians who take care of them are increasingly frustrated that there is still no fully satisfactory treatment. Much of this frustration results from the fact that the pathobiology of AA remains unclear, and no single AA pathogenesis concept can claim to be universally accepted. In fact, some investigators still harbour doubts whether this even is an autoimmune disease, and the relative importance of CD8+ T cells, CD4+ T cells and NKGD2+ NK or NKT cells and the exact role of genetic factors in AA pathogenesis remain bones of contention. Also, is AA one disease, a spectrum of distinct disease entities or only a response pattern of normal hair follicles to immunologically mediated damage? During the past decade, substantial progress has been made in basic AA‐related research, in the development of new models for translationally relevant AA research and in the identification of new therapeutic agents and targets for future AA management. This calls for a re‐evaluation and public debate of currently prevalent AA pathobiology concepts. The present Controversies feature takes on this challenge, hoping to attract more skin biologists, immunologists and professional autoimmunity experts to this biologically fascinating and clinically important model disease.

Prolactin—a novel neuroendocrine regulator of human keratin expression in situ

The controls of human keratin expression in situ remain to be fully elucidated. Here, we have investigated the effects of the neurohormone prolactin (PRL) on keratin expression in a physiologically and clinically relevant test system: organ‐cultured normal human hair follicles (HFs). Not only do HFs express a wide range of keratins, but they are also a source and target of PRL. Microarray analysis revealed that PRL differentially regulated a defined subset of keratins and keratin‐associated proteins. Quantitative immunohistomorphometry and quantitative PCR confirmed that PRL up‐regulated expression of keratins K5 and K14 and the epithelial stem cell‐associated keratins K15 and K19 in organ‐cultured HFs and/or isolated HF keratinocytes. PRL also up‐regulated K15 promoter activity and K15 protein expression in situ, whereas it inhibited K6 and K31 expression. These regulatory effects were reversed by a pure competitive PRL receptor antagonist. Antagonist alone also modulated keratin expression, suggesting that “tonic stimulation” by endogenous PRL is required for normal expression levels of selected keratins. Therefore, our study identifies PRL as a major, clinically relevant, novel neuroendocrine regulator of both human keratin expression and human epithelial stem cell biology in situ. —Ramot, Y., Bíro´, T., Tiede, S. To´th, B. I., Langan, E. A., Sugawara, K., Foitzik, K., Ingber, A., Goffin, V., Langbein, L., Paus, R. Prolactin—a novel neuroendocrine regulator of human keratin expression in situ. FASEB J. 24, 1768–1779 (2010). www.fasebj.org

Thyrotropin releasing hormone (TRH): a new player in human hair-growth control

Thyrotropin‐releasing hormone (TRH) is the most proximal component of the hypothalamic‐pituitary‐thyroid axis that regulates thyroid hormone synthesis. Since transcripts for members of this axis were detected in cultured normal human skin cells and since human hair follicles (HFs) respond to stimulation with thyrotropin we now have studied whether human HF functions are also modulated by TRH. Here we report that the epithelium of normal human scalp HFs expresses not only TRH receptors (TRH‐R) but also TRH itself at the gene and protein level. Stimulation of microdissected organ‐cultured HFs with TRH promotes hair‐shaft elongation prolongs the hair cycle growth phase (anagen) and antagonizes its termination by TGF‐β2. It also increases proliferation and inhibits apoptosis of hair matrix keratinocytes. These TRH effects may be mediated in part by reducing the ATM/Atr‐dependent phosphorylation of p53. By microarray analysis several differentially up‐ or down‐regulated TRH‐target genes were detected (e.g., selected keratins). Thus human scalp HFs are both a source and a target of TRH which operates as a potent hair‐growth stimulator. Human HFs provide an excellent discovery tool for identifying and dissecting nonclassical functions of TRH and TRH‐mediated signaling in situ, which emerge as novel players in human epithelial biology.—Gáspár, E., Hardenbicker, C., Bodó, E., Wenzel B. Ramot Y. Funk W. Kromminga A. Paus R. Thyrotropin releasing hormone (TRH): a new player in human hair‐growth control. FASEB J. 24, 393–403 (2010). www.fasebj.org

Endocrine controls of keratin expression

Keratins are a family of intermediate filaments that serve various crucial roles in skin physiology. For mammalian skin to function properly, and to produce epidermal and hair keratins that are optimally adapted for their environment, it is critical that keratin gene and protein expression are stringently controlled. Given that the skin is not only targeted by multiple hormones, but also constitutes a veritable peripheral endocrine organ, it is not surprizing that intracutaneous keratin expression is underlined by tight endocrine controls. These controls encompass thyroid hormones, steroid hormones such as glucocorticoids (GCs), retinoic acid (RA) and vitamin D, and several neuroendocrine mediators. Here, we review why a better understanding of the endocrine controls of keratin expression is not only required for an improved insight into normal human skin and hair function, but may also open new therapeutic avenues in a wide range of skin and hair diseases.

Safety and Biodistribution Profile of Placental-derived Mesenchymal Stromal Cells (PLX-PAD) Following Intramuscular Delivery

The administration of mesenchymal stromal cells (MSCs) provides an exciting emerging therapeutic modality for the treatment of peripheral arterial disease, a condition that is associated with critical limb ischemia as its end stage. Placental-derived MSCs, termed PLX-PAD cells, are stable adhesive stromal cells isolated from full-term human placentae, cultured on carriers, and expanded in a bioreactor called the PluriX. These cells can be expanded in vitro without phenotypic or karyotypic changes. We studied the safety and biodistribution properties of PLX-PAD cells following intramuscular administration in NOD/SCID mice. No significant clinical signs, hematological and biochemical parameters, or major pathological changes were found in PLX-PAD-treated animals in comparison to vehicle controls. Several animals in the control and PLX-PAD-treated groups developed thymic malignant lymphoma, first seen after one month, as expected in this mouse strain. In addition, both groups developed spontaneous mesenteric vessel inflammation. Real-time quantitative polymerase chain reaction (RT-qPCR) demonstrated that distribution of PLX-PAD cells was confined to the injection site. Placental-derived MSCs remained in this site with gradual decrease in concentration during a three-month period. In view of these data, we conclude that the administration of PLX-PAD cells is not associated with any adverse effects in NOD/SCID mice.

Chronic Atypical Neutrophilic Dermatosis with Lipodystrophy and Elevated Temperature Syndrome: A Case Report

Abstract:  Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome is a recently described chronic inflammatory syndrome consisting of widespread annular violaceous skin lesions and multisystemic inflammatory manifestations. We report a 12½‐year‐old boy with a young‐age onset of recurrent fevers, annular violaceous plaques, alopecia areata, lipodystrophy, low weight and height, deformed fingers, wide‐spaced nipples, chronic anemia, and elevated acute phase reactants. An abdominal punch biopsy demonstrated dense perivascular and interstitial infiltrates in the dermis, composed mainly of mononuclear cells. This syndrome may represent a new autosomal recessive auto‐inflammatory genodermatosis. Increased awareness may lead to the discovery of more cases, and clarify its pathogenesis.