Hair Bulb Research Articles

Australian Familial Haematological Cancer Study - Findings from 15 Years of Aggregated Clinical, Genomic and Transcriptomic Data

The Australian Familial Haematological Cancer Study (AFHCS) was initiated in 2004 with the aim to define genes predisposing to hematological malignancy (HM) to offer better options for clinical decision making and genetic counselling, and to identify therapeutic targets. The study is a referral centre for Australia and New Zealand, and currently has 230 families with multiple cases of myeloid and/or lymphoid malignancies or early onset cases (Figure 1), and is growing as clinical awareness of a germline genetic basis for blood cancers increases. To date, we have identified families with causal germline variants in several predisposition genes (five GATA2, ten RUNX1, one CEBPA, ten DDX41, one SAMD9L) including novel single nucleotide variants, deletions and insertions in coding and intronic sequences using traditional Sanger sequencing and now genomic and transcriptomic technologies. Of these, one GATA2 and four DDX41 germline mutations were identified during the screening of "sporadic" MDS samples. All four DDX41 mutant samples also harbored a somatic DDX41 (R525H) variant on the other allele at a low variant allele frequency. A comprehensive clinical analysis of the RUNX1 families has uncovered segregating phenotypes, in addition to thrombocytopenia and myeloid and lymphoid malignancies, including skin disorders such as psoriasis. In an increasing number of individuals in these families, important clinical decisions have been made dependent on mutation carrier status. Recently, we have identified and characterized a unique myeloproliferative neoplasm (MPN)/acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) family with a germline Chr14q duplication that overlaps with duplications in two other reported MPN/AML families. This appears to be a unique genotypic/phenotypic entity when compared to other myeloid predisposition genes and their associated phenotypes. Interestingly, we have identified several families carrying heterozygous pathogenic/likely pathogenic variants in genes representing autosomal recessive genomic instability syndromes segregating with HM. Here mutations in the genes NBN, RECQL4, DDX11 and RAD21 appear to act in an autosomal dominant manner. Further, we have found DNA damage repair gene predicted pathogenic variants in PALB2 and BARD1 in families with both solid cancers and HM, predominantly lymphomas, implicating an expansion of the major predisposition phenotype of these gene perturbations. Familial cases of chronic lymphocytic leukemia (CLL) have been well recognized, but it has been particularly difficult to identify predisposing variants. We have identified a number of strong candidate genes/variants in CLL families including PRPF8 (Y208C and N400S) and SAMHD1 (R371H) although more families are required to confirm these. An integral part of the AFHCS is the continued generation of cell and animal models to help define mechanisms of action of predicted or known pathogenic variants, and functional model systems for testing of variants of unknown significance. To facilitate the collection of patient samples, we have adopted the use of hair bulbs as the main germline sample as they are easy to collect, can be easily sent long distance by mail at room temperature, require no culture, are quickly and cheaply processed and provide good quality DNA using automated procedures. Overall, collaborative efforts within Australia and New Zealand and internationally have been highly fruitful in solving familial cases of hematopoietic malignancies over the last 15 years, and even more concerted international efforts will be required in the future to uncover the familial basis of unsolved cases, particularly in the lymphoid lineage, and to clarify best approaches for clinical decision making and treatment options. Figure 1. Summary of AFHCS families with associated hematological malignancies. Figure Disclosures Scott: Celgene: Honoraria.

Drug Delivery System Based On Minoxidil Nanoparticles Promotes Hair Growth In C57BL/6 Mice.

PurposeWe designed formulations based on minoxidil (MXD) nanoparticles (N-MXD) and examined whether N-MXD can increase drug delivery into the follicles. In addition, we investigated the effect of N-MXD on hair growth in C57BL/6 mice.MethodsN-MXD (1%) was prepared as follows: methylcellulose, p-hydroxyalkylbenzoates, mannitol, and MXD were dispersed in purified water and milled using zirconia beads under refrigeration (5500 rpm, 30 s×15 times, intermittent milling). C57BL/6 mice were used to evaluate hair-growth effects. The expression levels of mRNA and protein for vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) were determined by real-time PCR and ELISA methods, respectively.ResultsThe ratio of solid-MXD was approximately 60% in N-MXD, and the MXD nanoparticles (90–300 nm) were oblong in shape. For the design of nanomedicines, usability is important. Therefore, we measured the stability and toxicity after N-MXD treatment. No agglutination of MXD nanoparticles was detected for 2 weeks, and no redness or MXD powder residue was observed in the skin after repetitive applications of N-MXD. Next, we evaluated hair-growth effects by N-MXD treatment. MXD contents in the skin tissue from N-MXD were lower than for commercially available MXD formulations (CA-MXD). Conversely, MXD contents in the hair bulbs were higher for N-MXD than for CA-MXD, and the drug efficacy of N-MXD was also higher than that of CA-MXD. In addition, the mRNA and protein levels of IGF-1 and VEGF were enhanced by the repetitive application of N-MXD and CA-MXD, and the enhanced IGF-1 and VEGF levels were significantly higher for N-MXD than for CA-MXD.ConclusionWe designed a novel nanomedicine based on MXD nanoparticles and showed that N-MXD can deliver MXD into hair bulbs via hair follicles and that the therapeutic efficiency for hair growth is higher than for CA-MXD (solution type).

Poly(γ-Glutamic Acid)/Chitosan Hydrogel Nanoparticles For Effective Preservation And Delivery Of Fermented Herbal Extract For Enlarging Hair Bulb And Enhancing Hair Growth.

IntroductionHair growth-promoting herbal extract mixtures (4HGF) exhibits significant anti-inflammatory activities relevant to promoting hair growth; however, its efficacy in patients with hair loss has been limited majorly due to its low penetration ability into hair follicles. Herein, we prepared hydrogels via dropwise addition of poly(γ-glutamic acid) (PGA) solution containing 4HGF into chitosan (CS) solution, resulting in quick formation of ~400 nm-sized hydrogel particles through electrostatic interaction-derived ionic gelation with over 50% encapsulation efficiency of 4HGF (PGA-4HGF).MethodsThe size and morphology of PGA-4HGF were characterized by TEM, SEM, and dynamic light scattering analyses. Encapsulation efficiency and loading capacity of 4HGF within PGA-4HGF, as well as in vitro release profiles were determined by simply measuring the characteristic absorbance of 4HGF. Penetrating efficiency of PGA-4HGF was evaluated by tracking the respective fluorescence through model porcine skin with confocal laser microscope system. By treating PGA-4HGF on telogenic mice and dermal papilla cells (DPCs), we evaluated the size of hair bulbs in mice, as well as morphological changes in DPCs.ResultsNegligible and sustained release of entrapped 4HGF from the hydrogel nanoparticles were observed under acidic and physiological pH conditions, respectively, which is quite advantageous to control their release and prolong their hair growth-promoting effect. The hydrogel nanoparticles were penetrable through the porcine skin after incubation with or without shaking. After treating telogenic mice and DPCs with PGA-4HGF, we detected enlargement of hair bulbs and remarkable shape changes, respectively, thereby showing its potential in induction of hair growth.ConclusionThese results suggest that the hydrogel nanoparticle formulation developed in this study can be employed as a potential approach for the preservation of hair growth-promoting compounds, their delivery of into hair follicles, and enhancing hair growth.

083 More Expression of IL-17 than IFN-γ from CD49a-negative Tissue-Resident Memory T (Trm) cells at the Hair Bulge and Hair Bulb Region in the Scalp of Chronic Alopecia Areata Patients according to the Foxp3+mTregs depletion

083 More Expression of IL-17 than IFN-γ from CD49a-negative Tissue-Resident Memory T (Trm) cells at the Hair Bulge and Hair Bulb Region in the Scalp of Chronic Alopecia Areata Patients according to the Foxp3+mTregs depletion

Effects of the selective TrkA agonist gambogic amide on pigmentation and growth of human hair follicles in vitro.

The human hair follicle is a neuroendocrine mini-organ that can be used to study aging processes in vitro. Neurotrophins maintain homeostasis in hair biology via the Trk-family of receptors. TrkA, the high affinity receptor for nerve growth factor (NGF), is expressed in hair follicle melanocytes and keratinocytes, where it regulates proliferation, differentiation and apoptosis and may thereby play a role in hair pigmentation and growth. We investigated TrkA expression during the human hair cycle and the effects of a selective high affinity TrkA agonist, Gambogic Amide, on hair pigmentation and hair growth in human hair follicles in vitro. In human scalp skin, TrkA expression was strongest in proliferating melanocytes re-establishing the pigmentary unit in the hair bulb during the early hair growth phase, anagen. During high anagen and in the de-composing pigmentary-unit of the regression phase, catagen, bulb-melanocytes lost TrkA expression and only undifferentiated outer root sheath melanocytes maintained it. In cultured human anagen hair follicles, Gambogic Amide was able to prevent gradual pigment loss, while it stimulated hair shaft elongation. This was achieved by increased melanocyte activation, migration and dendricity, highlighted by distinct c-KIT-expression in melanocyte sub-populations. Our results suggest that Gambogic Amide can maintain hair follicle pigmentation by acting on undifferentiated melanocytes residing in the outer root sheath and making them migrate to establish the pigmentary-unit. This suggests that the selective TrkA agonist Gambogic Amide acts as an anti-hair greying and hair growth promoting molecule in vitro.

HIrisPlex-S system for eye, hair, and skin color prediction from DNA: Massively parallel sequencing solutions for two common forensically used platforms

Forensic DNA Phenotyping (FDP) provides the ability to predict externally visible characteristics from minute amounts of crime scene DNA, which can help find unknown perpetrators who are typically unidentifiable via conventional forensic DNA profiling. Fundamental human genetics research has led to a better understanding of the specific DNA variants responsible for physical appearance characteristics, particularly eye, hair, and skin color. Recently, we introduced the HIrisPlex-S system for the simultaneous prediction of eye, hair, and skin color based on 41 DNA variants generated from two forensically validated SNaPshot multiplex assays using capillary electrophoresis (CE). Here we introduce massively parallel sequencing (MPS) solutions for the HIrisPlex-S (HPS) system on two MPS platforms commonly used in forensics, Ion Torrent and MiSeq, that cover all 41 DNA variants in a single assay, respectively. Additionally, we present the forensic developmental validation of the two HPS-MPS assays. The Ion Torrent MPS assay, based on Ion AmpliSeq technology, illustrated the successful generation of full HIrisPlex-S genotypic profiles from 100 pg of input control DNA, while the MiSeq MPS assay based on an in-house design yielded complete profiles from 250 pg of input DNA. Assessing simulated forensic casework samples such as saliva, hair (bulb), blood, semen, and low quantity touch DNA, as well as artificially damaged DNA samples, concordance testing, and samples from numerous species, all illustrated the ability of both versions of the HIrisPlex-S MPS assay to produce results that motivate forensic applications. By also providing an integrated bioinformatics analysis pipeline, MPS data can now be analyzed and a file generated for upload to the publically accessible HIrisPlex online webtool (https://hirisplex.erasmusmc.nl). In addition, we updated the website to accept VCF input data for those with genome sequence data. We thus provide a user-friendly and semi-automated MPS workflow from DNA sample to individual eye, hair, and skin color prediction probabilities. Furthermore, we present a 2-person mixture separation tool that not only assesses genotype reliability with regards genotyping confidence but also provides the most fitting mixture scenario for both minor and major contributors, including profile separation. We envision this MPS implementation of the HIrisPlex-S system for eye, hair, and skin color prediction from DNA as a starting point for further expanding MPS-based forensic DNA phenotyping. This may include the future addition of SNPs predictive for more externally visible characteristics, as well as SNPs for bio-geographic ancestry inference, provided the statistical framework for DNA prediction of these traits is in place.

Optical features of human skin revealed by optoacoustic mesoscopy in the visible and short-wave infrared regions.

Detailed assessment of skin conditions or the efficacy of skin treatments could greatly benefit from noninvasively assessing the distribution of cutaneous and subcutaneous structures and biomolecules. We considered ultrawideband raster scan optoacoustic mesoscopy with an extended wavelength range from visible to short-wave infrared and observed previously unseen high-resolution images of lipids colocalized with water, melanin, and hemoglobin distribution in human skin. Based on this contrast, the technique resolves subcutaneous fat, the pilosebaceous unit with complete hair strand and bulb, dermal microvasculature, and epidermal structures. We further visualize melanoidins that form via the Maillard reaction in the ultrathin stratum corneum layer, analyze their absorption spectrum, and separate them from the melanin layer. The suggested method may allow novel interrogation of skin conditions, possibly impacting diagnostics and medical and cosmetic treatments.

Optical coherence tomography in forensic sciences: a review of the literature.

Optical coherence tomography (OCT) is an interferometric imaging technique that has revolutionized clinical ophthalmology since the first half of the 1990's. Despite this approach being successfully employed in ophthalmology and having great potential in forensic cases, its use in different forensic fields appears to be quite limited. In this review we reviewed the scientific literature regarding the application of OCT in forensic science and legal medicine from 1995 to 2019. Our research showed the usefulness of this approach for the study of coronary injuries, postmortem ocular changes, forensic entomology, and several other applications of specific forensic interest (the study of blood stains, fingerprints, and hair bulbs for personal identification, as well as the study of materials found in the crime scene for comparation, or anti-fraud investigation). The creation of specific 'ad hoc' devices and a better knowledge of this type of technology by pathologists will be a fundamental step to continue to develop the use of OCT forensic fields.

Abstract 4947: Plucked anagen scalp hair: A comparison between different analytical techniques to establish reproducible drug induced transcriptional changes and provide pharmacodynamic biomarker and target engagement information from oncology patients

Abstract Plucked anagen scalp hair is an ideal surrogate tissue to monitor drug induced transcriptional changes. High vascularisation of the hair follicle, ease of sampling and high degree of similarity of expression in hair of pathways dysregulated in cancers, make the cellular bulb of plucked human scalp hair an excellent surrogate tissue for the non-invasive monitoring of pharmacodynamic (PD) and mechanism of action (MOA) effects in clinical trials. Using our ex vivo plucked hair culture platform, plucked scalp hair bulbs from several healthy donors were exposed to BEZ235, a dual pan-class PI3K and mTOR inhibitor at different concentrations and durations. Total RNA was isolated from the cellular bulb of anagen hair post-culture and samples were assessed by microarray and RNA-seq analysis to assess dose dependent global transcriptional alterations and develop a gene expression signature indicative of BEZ235 exposure. Two different microarrays, the Affymetrix Clariom D and U133 plus 2.0 arrays, were directly compared to RNA-seq data obtained from the same ex vivo culture samples. Genetic signatures indicative of exposure of plucked scalp hair to BEZ235 were established using all three analytical techniques. The transcriptional readouts from the plucked scalp hair samples revealed strong correlations (0.97-0.99) in the genes expressed in anagen scalp hair between donors. In addition, global gene expression data indicated that assessing pooled scalp hairs was sufficient to detect significant differential expression (p<0.05 & 1.5 fold change) underpinning the low variance in the majority of target genes in plucked hair as a biomarker platform. Gene signatures for compounds targeting the PI3K/mTOR pathway that were established using the ex vivo plucked scalp hair platform were subsequently used to support clinical trials and scalp hair taken from patients receiving treatment showed an excellent post-exposure target signature modulation. In summary, the results of the ex vivo plucked assessment generated a dose dependent and biologically relevant transcriptional signature following exposure to BEZ235. Plucked anagen scalp hair is therefore an ideal non-invasive surrogate tissue to obtain drug-induced pharmacodynamic biomarker and target engagement information from oncology patients. Citation Format: Tim Mefo, Elliott Harrison, Alan Murdoch, Benjamin Reed. Plucked anagen scalp hair: A comparison between different analytical techniques to establish reproducible drug induced transcriptional changes and provide pharmacodynamic biomarker and target engagement information from oncology patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4947.

Human Perifollicular Macrophages Undergo Apoptosis, Express Wnt Ligands, and Switch their Polarization during Catagen

Human Perifollicular Macrophages Undergo Apoptosis, Express Wnt Ligands, and Switch their Polarization during Catagen

Progressive expression of PPARGC1\u03b1 is associated with hair miniaturization in androgenetic alopecia

Current opinion views androgens as the pathogenic driver in the miniaturization of hair follicles of androgenetic alopecia by interfering with the dermal papilla. This cannot be the sole cause and therefore it is important for therapeutic and diagnostic purposes to identify additional pathways. Comparative full transcriptome profile analysis of the hair bulb region of normal and miniaturized hair follicles from vertex and occipital region in males with and without androgenetic alopecia revealed that next to the androgen receptor as well the retinoid receptor and particularly the PPAR pathway is involved in progressive hair miniaturization. We demonstrate the concurrent up-regulation of PPARGC1a in the epithelial compartment and androgen receptor in the dermal papilla of miniaturized hair. Dynamic Ppargc1a expression in the mouse hair cycle suggests a possible role in regulating hair growth and differentiation. This is supported by reduced proliferation of human dermal papilla and predominantly epithelial keratinocytes after incubation with AICAR, the agonist for AMPK signaling which activates PPARGC1a and serves as co-activator of PPARγ. In addition, miRNA profiling shows enrichment of miRNA-targeted genes in retinoid receptors and PPARGC1α/PPARγ signaling, and antigen presentation pathways.

“Miliacin encapsulated by polar lipids stimulates cell proliferation in hair bulb and improves telogen effluvium in women”

Miliacin, the main triterpenoid from millet, is known to stimulate keratinocyte metabolism and proliferation. Polar lipids are able to form vesicles with active compounds and to improve their bioavailability. We aimed to demonstrate potential benefits of a solution of miliacin encapsulated within polar lipids (MePL) on telogen effluvium prevention and hair condition in women. After preliminary cell proliferation studies, a placebo-controlled, multicentric, randomized, double-blind trial was performed on sixty-five nonmenopausal women affected by telogen effluvium, to assess the efficacy of a 12-week oral supplementation with MePL. Telogen and anagen densities were determined by phototrichogram analysis. Scalp dryness and hair brightness were clinically evaluated using a Likert scale. MePL further enhanced cell proliferation in hair bulb from human scalp than miliacin alone. Compared to the placebo treatment, MePL supplementation significantly reduced telogen density after 12weeks of treatment. An increase of anagen density was observed in both groups, although there was no significant difference between the two treatments. Scalp dryness was more decreased in the MePL group than in the placebo group. A better improvement of hair brightness was also observed after 12weeks of supplementation with MePL. Twelve weeks of MePL supplementation significantly reduced the hair density in the telogen phase and, in parallel, improved scalp dryness and hair condition. These effects could be linked to MePL activity on cell proliferation in hair bulb. MePL is an original association of plant extract that could help to prevent and/or limit hair loss in women.

Bacillus/Trapa japonica Fruit Extract Ferment Filtrate enhances human hair follicle dermal papilla cell proliferation via the Akt/ERK/GSK-3\u03b2 signaling pathway

BackgroundDespite advances in medical treatments, the proportion of the population suffering from alopecia is increasing, creating a need for new treatments to control hair loss and prevent balding. Treatments based on plant-derived compounds could potentially prevent hair loss. Human hair follicle dermal papilla (HDP) cells, a type of specialized fibroblast in the hair bulb, play an essential role in controlling hair growth and in conditions such as androgenic alopecia. We examined the effect of Bacillus/Trapa japonica fruit ferment filtrate extracts (TJFs) on HDP cells to determine whether activation of the Akt/ERK/GSK-3β signaling pathway improved HDP cell proliferation.MethodsWe prepared TJFs using various methods. The extract properties were analyzed using WST-1, Lowry, and cell migration assays as well as immunofluorescence staining. We also determined the cell cycle stage and performed western blotting and an in ovo chick chorioallantoic membrane assay. Last, we constructed an organotypic three-dimensional cell culture model for immunohistochemical use.ResultsOur study confirmed that the TJFs contained numerous peptides and five unknown fractions. The TJFs stimulated HDP cell proliferation and migration via the Akt/ERK/GSK-3β signaling pathway. To verify that the Akt/ERK/GSK-3β pathway affected HDP cell proliferation, we treated HDP cells with LY294002 (an Akt inhibitor), BIO (a GSK-3β inhibitor), and PD98059 (an ERK inhibitor). The TJFs also induced cell cycle progression, inhibited type І 5α-reductase, decreased apoptosis, and enhanced angiogenesis (vascular expansion). In addition to these signaling pathways, proteins including insulin-like growth factor-1 and keratinocyte growth factor, stimulating hair growth, were detected in the three-dimensional cell culture model.ConclusionsOur results confirmed that TJFs enhance HDP cell proliferation via the Akt/ERK/GSK-3β signaling pathway, suggesting a potential treatment for alopecia.

Incorporation of zolpidem and methoxyphenamine into white hair strands after single administrations: Influence of hair pigmentation on drug incorporation

In order to investigate the influence of pigmentation on the incorporation of drugs into hair, time-course changes in drug distribution along non-pigmented (white) hairs as well as pigmented (black) hairs plucked from the same subject was observed following single administrations of two basic drugs with different properties, zolpidem and methoxyphenamine. These drugs in 1-mm sections of single hair specimens were each determined by a liquid chromatography–tandem mass spectrometric procedure. During the early stage (12–36 h) after intake, for black hairs, both drugs were detected over the entire area of hair root (4–5 mm in length), in which notable concentration of these drugs in the hair bulb (0–1-mm segment from the bottom of hair root, Region 1) and lower concentrations in the upper dermis zone (1–2-mm to 3–4-mm or to 4–5-mm segments, Region 2) were commonly observed. Meanwhile, for white hairs, high drug concentrations in Region 1 as detected in black hairs were not observed although only small amounts of these drugs were detected over Region 2. Subsequent time-course changes in the concentration of drugs in hair demonstrated that the drugs once incorporated into white hair via Region 2 decreased gradually over the period from 24 h to 35 days after intake, but those of black hairs remained almost unchanged. These findings revealed here suggest that hair pigments have two important roles in the distribution of drugs: (1) incorporation of drugs into hair via Region 1, and (2) retention of already incorporated drugs in the hair tissue. These findings would be useful for discussing individual drug-use history based on hair analysis in the forensic fields.

Hair Testing for Drugs in the Field of Forensics

Hair testing for drugs has been used extensively in the field of forensics since the 1990s as a means of obtaining firm evidence of drug ingestion. In addition to its longer detection windows, hair is the only specimen that can provide chronological information on individual drug use. Illicit drugs and hypnotics account for the majority of substances involved in crimes; they are usually analyzed to prove an addictive use or an exposure to drugs in drug-facilitated crimes. The mechanism of drug incorporation into hair has been intensively investigated to properly interpret the results of hair analysis. However, the exact mechanism remains under much discussion, despite the growing application of hair tests. Recently, the authors have applied matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) imaging and sectional hair analysis of 1-mm segments using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for single-strand hair, to investigate the incorporation pathways of drugs into hair. Time-course changes in drug distribution along single-strand hair suggest that the incorporation of drugs occurs in two regions of the hair root, the hair bulb and the upper part of hair root, and suggest that incorporation from the hair bulb continues for about 2 weeks. Distribution profiles of different drugs in hair additionally revealed that the main incorporation pathway varies (i.e., via the hair bulb or the upper part of hair root) depending on the properties of the drug/metabolite. These findings should be taken into account upon discussing individual drug-use history based on the results of hair analysis.

Histopathology of aging of the hair follicle.

Hair follicles experience several changes with aging, the most noticeable of which is graying of the hair shaft due to loss of melanin. Additional changes in the diameter and length of the hair have contributed to the concept of senescent alopecia, which is different from androgenetic alopecia according to most. Graying happens in most individuals, although in different grades and starting at different ages. It is related to a decrease in the number and activity of the melanocytes of the hair bulb, which eventually completely disappear from the bulb of the white hair. Residual non-active melanocytes remain in the outer root sheath and in the bulge, which allows for repigmentation of the hair under certain stimuli or conditions.

The Association between Genetic Variation in Wnt Transcription Factor TCF7L2 (TCF4) and Alopecia Areata

ABSTRACTBackground: Alopecia areata (AA) is a non-scarring hair loss with a polymorphous presentation ranging from patchy lesions to involvement of the entire scalp. The disease is the consequence of an autoimmune attack on hair bulbs that results in a premature transition of hair follicles to catagen and telogen. Thus the Wnt/β-catenin signaling pathway that regulates the hair cycling might be involved in the pathogenesis of AA. Genetic variations in the components of Wnt/β-catenin could greatly alter their adaptive mechanisms against an immunologic attack.Objectives: Our aim was to investigate the association between AA and genetic polymorphisms in the TCF7L2 gene, one of the most important components of the Wnt/β-catenin pathway.Methods: This is a case-control study of 145 patients with AA and 152 healthy controls. Genotyping of the TCF7L2 gene (rs7903146) was performed via the ARMS—PCR method (amplification refractory mutation system- polymerase chain reaction). The allele and genotype distribution was compared between the two groups.Results: The frequency of the T allele (0.38 vs. 0.28, odds ratio = 1.56, 95% CI = 1.09–2.17, p = 0.013) and TT + CT genotypes (0.68 vs. 0.53, odds ratio = 1.88, 95% CI = 1.17–3.02, p = 0.008) were significantly higher in AA patients.Conclusions: This study indicates that the TCF7L2 gene variant is associated with AA. Its contribution to disease pathogenesis could either be through a hair cycling defect or dendritic cell dysregulation.

504 CERKL expression enhances survival in cutaneous squamous cell carcinoma

Ceramide Kinase-Like Protein (CERKL) was originally described in retinal tissue. CERKL is thought to protect cells from oxidative stress, and mutations in CERKL underlie the inherited disease retinitis pigmentosa. Using RNA-seq and qPCR, we find that CERKL is upregulated in cutaneous squamous cell carcinoma (cSCC), as compared to normal keratinocytes or normal epidermis. Immunostaining confirms that CERKL expression is increased in cSCC and actinic keratosis compared to normal intrafollicular epidermis, and also is upregulated in metabolically active sites such as the hair bulb and sebaceous glands. CERKL protects cSCC cells from oxidative stress, as CERKL inactivation with siRNA leads to increased apoptosis when cSCC cells are exposed to oxidative stress through H2O2. These findings demonstrate that CERKL is important in cSCC survival and may lead to novel strategies for prevention or treatment of cSCC.

Sustained Human Hair Follicle Growth Ex Vivo in a Glycosaminoglycan Hydrogel Matrix.

Glycosaminoglycans (GAGs) and associated proteoglycans have important functions in homeostatic maintenance and regenerative processes (e.g., wound repair) of the skin. However, little is known about the role of these molecules in the regulation of the hair follicle cycle. Here we report that growing human hair follicles ex vivo in a defined GAG hydrogel mimicking the dermal matrix strongly promotes sustained cell survival and maintenance of a highly proliferative phenotype in the hair bulb and suprabulbar regions. This significant effect is associated with the activation of WNT/β-catenin signaling targets (CCDN1, AXIN2) and with the expression of stem cell markers (CK15, CD34) and growth factors implicated in the telogen/anagen transition (TGFβ2, FGF10). As a whole, these results point to the dermal GAG matrix as an important component in the regulation of the human hair follicle growth cycle, and to GAG-based hydrogels as potentially relevant modulators of this process both in vitro and in vivo.

Therapeutic Potential of Patient iPSC-Derived iMelanocytes in Autologous Transplantation

Induced pluripotent stem cells (iPSCs) are a promising melanocyte source as they propagate indefinitely and can be established from patients. However, the invivo functions of human iPSC-derived melanocytes (hiMels)remain unknown. Here, we generated hiMels from vitiligo patients using a three-dimensional system with enhanced differentiation efficiency, which showed characteristics of human epidermal melanocytes with high sequence similarity and involved inmultiple vitiligo-associated signaling pathways. A modified hair follicle reconstitution assay invivo showed that MITF+PAX3+TYRP1+ hiMels were localized in the mouse hair bulb and epidermis and produced melanin up to 7weeks after transplantation, whereas MITF+PAX3+TYRP1- hiMelanocyte stem cells integrated into the bulge-subbulge regions. Overall, these data demonstrate the long-term functions of hiMels invivo to reconstitute pigmented hair follicles and to integrate into normal regions for both mature melanocytes and melanocyte stem cells, providing an alternative source of personalized cellular therapy for depigmentation.