Challenges in Treating Genodermatoses: New Therapies at the Horizon

The development of hair follicles and nail

The hair follicle and nail unit develop and regenerate through epithelial-mesenchymal interactions. Here, we review some of the key signals and molecular interactions that regulate mammalian hair follicle and nail formation during embryonic development and how these interactions are reutilized to promote their regeneration during adult homeostasis and in response to skin wounding. Finally, we highlight the role of some of these signals in mediating human hair follicle and nail conditions.

Advances in skin gene therapy: utilizing innovative dressing scaffolds for wound healing, a comprehensive review

The skin, serving as the body's outermost layer, boasts a vast area and intricate structure, functioning as the primary barrier against external threats. Disruptions in the composition and functionality of the skin can lead to a diverse array of skin conditions, such as wounds, burns, and diabetic ulcers, along with inflammatory disorders, infections, and various types of skin cancer. These disorders not only exacerbate concerns regarding skin health and beauty but also have a significant impact on mental well-being. Due to the complexity of these disorders, conventional treatments often prove insufficient, necessitating the exploration of new therapeutic approaches. Researchers develop new therapies by deciphering these intricacies and gaining a thorough understanding of the protein networks and molecular processes in skin. A new window of opportunity has opened up for improving wound healing processes because of recent advancements in skin gene therapy. To enhance skin regeneration and healing, this extensive review investigates the use of novel dressing scaffolds in conjunction with gene therapy approaches. Scaffolds that do double duty as wound protectors and vectors for therapeutic gene delivery are being developed using innovative biomaterials. To improve cellular responses and speed healing, these state-of-the-art scaffolds allow for the targeted delivery and sustained release of genetic material. The most recent developments in gene therapy techniques include RNA interference, CRISPR-based gene editing, and the utilization of viral and non-viral vectors in conjunction with scaffolds, which were reviewed here to overcome skin disorders and wound complications. In the future, there will be rare chances to develop custom methods for skin health care thanks to the combination of modern technology and collaboration among disciplines.

Investigating the Prevalence, Gender Predilection, and Inheritance Patterns of Genodermatoses: A Tertiary Hospital Study

Genodermatoses encompass a spectrum of hereditary skin disorders stemming from mutations in genes pivotal for skin development, structure, and function. This study investigated the prevalence, gender predilection, and inheritance patterns of genodermatoses in a tertiary-level hospital through a one-year observational study. Among 157,051 dermatology outpatient department patients, 105 cases of genodermatoses were diagnosed, yielding a prevalence rate of 0.067%. Hamartoneoplastic syndromes and inherited disorders of cornification were the most prevalent subgroups, with neurofibromatosis type 1 and tuberous sclerosis complex 1 leading within these categories. The average age at presentation varied among different subgroups. A 2:1 male-to-female ratio was observed across all subgroups. Autosomal dominant inheritance was predominant. A positive family history in 46 cases and consanguinity among parents in 28 instances was reported. Genodermatoses pose diagnostic challenges due to their clinical complexity and rarity, which is compounded by limited epidemiological data. Molecular diagnosis advancements offer insights into genotype-phenotype correlations and facilitate genetic counseling and prenatal diagnosis (PND). Raising awareness among healthcare professionals and the public is critical for improving the quality of life for affected individuals.

Th17-associated cytokines IL-17 and IL-23 in inflamed skin of Darier disease patients as potential therapeutic targets

Darier disease (DD) is a rare, inherited multi-organ disorder associated with mutations in the ATP2A2 gene. DD patients often have skin involvement characterized by malodorous, inflamed skin and recurrent, severe infections. Therapeutic options are limited and inadequate for the long-term management of this chronic disease. The aim of this study was to characterize the cutaneous immune infiltrate in DD skin lesions in detail and to identify new therapeutic targets. Using gene and protein expression profiling assays including scRNA sequencing, we demonstrate enhanced expression of Th17-related genes and cytokines and increased numbers of Th17 cells in six DD patients. We provide evidence that targeting the IL-17/IL-23 axis in a case series of three DD patients with monoclonal antibodies is efficacious with significant clinical improvement. As DD is a chronic, relapsing disease, our findings might pave the way toward additional options for the long-term management of skin inflammation in patients with DD.

Advances in the treatment of autosomal recessive congenital ichthyosis, a look towards the repositioning of drugs

Autosomal recessive congenital ichthyoses (ARCI) are a skin pathology due to genetic causes characterized by a variable degree of desquamation, accompanied by erythema. The degree of symptoms is variable, different altered genes are involved, and the symptoms drastically affect patients' quality of life. Topical treatments are a first-choice strategy due to their ease of application and cost; however, enteral administration of retinoids offers greater efficacy, although with certain limitations. Despite the treatment alternatives, ARCI will persist throughout life, disabling people. Therefore, the search for new treatments always remains necessary. Especially repositioning drugs could be a short-term alternative to new affordable treatments for patients. Taking advantage of extensive knowledge of known drugs or biologics could ensure more accessible and possibly lower-cost treatments. This review briefly and concisely addresses possible repositioning strategies with drugs and biologics for ichthyosis.

[Dermoscopy of genodermatoses]

Genodermatoses are a group of inherited skin diseases whose diagnosis is challenging due to their rarity as well as their clinical and genetic diversity. The majority of genodermatoses are autosomal or X‑linked inherited, but mosaic forms are also observed. Genodermatoses comprise various phenotypes ranging from limited cutaneous disease to severe cutaneous and extracutaneous involvement and may also be early warning signs of a multisystemic disorder. Despite recent advances in genetic technology and skin imaging modalities, dermoscopy can be useful for screening, diagnosis, and treatment follow-up. In ectopic mineralization and lysosomal storage disorders (pseudoxanthoma elasticum and Fabry disease, respectively), cutaneous manifestations may indicate involvement of other organs. In keratinization diseases (e.g., ichthyoses) and acantholytic skin fragility disorders (e.g., Darier and Hailey-Hailey disease), dermoscopy may help to assess treatment response by visualizing background erythema, hyperkeratosis, and interkeratinocyte space prominence. Dermoscopy is a noninvasive, easily accessible, useful, in vivo assessment tool that is well established in dermatology to recognize characteristic features of genodermatoses.

Differentiation of pluripotent stem cells for modeling human skin development and potential applications

The skin of mammals is a multilayered and multicellular tissue that forms an environmental barrier with key functions in protection, regulation, and sensation. While animal models have long served to study the basic functions of the skin in vivo, new insights are expected from in vitro models of human skin development. Human pluripotent stem cells (PSCs) have proven to be invaluable tools for studying human development in vitro. To understand the mechanisms regulating human skin homeostasis and injury repair at the molecular level, recent efforts aim to differentiate PSCs towards skin epidermal keratinocytes, dermal fibroblasts, and skin appendages such as hair follicles and sebaceous glands. Here, we present an overview of the literature describing strategies for human PSC differentiation towards the components of skin, with a particular focus on keratinocytes. We highlight fundamental advances in the field employing patient-derived human induced PSCs (iPSCs) and skin organoid generation. Importantly, PSCs allow researchers to model inherited skin diseases in the search for potential treatments. Skin differentiation from human PSCs holds the potential to clarify human skin biology.