Hair Follicle Tissue Research Articles

CircCSPP1 Competitively Binds miR-10a to Regulate BMP7 Expression and Affects the Proliferation of Dermal Papilla Cells.

A series of differentially expressed circular RNAs (circRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs) were identified through sequencing in the hair follicle tissues of Hu sheep with small-waved and straight wool patterns. Based on these findings, the circCSPP1-miR-10a-BMP7 (Bone Morphogenetic Protein 7) regulatory network was constructed. The preliminary study highlighted that miR-10a and the BMP7 gene exhibited not only significant differential expression across hair follicle tissues with different patterns in Hu sheep but also had an impact on the proliferation of hair papilla cells. The proliferation of hair papilla cells is intricately linked to hair follicle development and growth. Consequently, we selected the circCSPP1-miR-10a-BMP7 regulatory network to validate its role in promoting hair papilla cell proliferation in Hu sheep. Firstly, the authenticity of circCSPP1 was successfully confirmed through RNase R digestion and reverse primer amplification. Additionally, nucleoplasmic localization analysis determined that circCSPP1 was predominantly distributed in the cytoplasm. Using the dual-luciferase gene reporter system, we verified the targeting relationship between circCSPP1 and miR-10a, building upon our previous validation of the miR-10a-BMP7 interaction. This clarified the competing endogenous RNA (ceRNA) mechanism within the circCSPP1-miR-10a-BMP7. Furthermore, rescue experiments confirmed that circCSPP1 competitively binds to miR-10a, thereby regulating BMP7 expression and influencing the proliferation of hair papilla cells in Hu sheep. This discovery provides a solid foundation for future investigations into the mechanisms underlying wool curvature and the formation of lambskin patterns, offering insights into the complex regulatory networks that govern these phenotypic traits in Hu sheep.

Unique feather color characteristics and transcriptome analysis of hair follicles in Liancheng White ducks

Avian feather color is a fascinating trait, and the genetic mechanism of duck plumage formation is still in the preliminary stage. In this study, feather color of Liancheng White ducks was analyzed by determination of melanin content and RNA-seq analysis. In this research, 9 ducks from Mallards (n = 3), Liancheng White (n = 3) and Pekin ducks (n = 3) were used by high performance liquid chromatography (HPLC) and Masson-Fontana staining to reveal the difference of feather melanin content. RNA-seq from 11 hair follicle tissues (1- and 8-wk-old) of Liancheng White ducks (n = 5) and Pekin ducks (n = 7) was used to analyze the candidate genes for the feather melanin synthesis, and Immunofluorescence experiment was used to show the protein expression in 6 black- and white-feathered ducks. Pectorale, skin, liver, fat, brain, heart, kidney, lung, spleen of an 8-wk-old black-feathered Mallard were collected for candidate gene expression. The results showed that the contents of feathers, beak, web melanin in Liancheng White ducks were higher than in Pekin ducks (p < 0.05). Melanin within hair follicles was located in the barb ridge and hair matrix of black feather duck, also we found that TYRP1, TYR, SOX10 genes were differentially expressed between Liancheng White and Pekin ducks (p < 0.05), and these genes were mainly expressed showed in duck skin tissues. This study revealed the unique feather color phenotype of Liancheng White duck shedding light on the transcriptome that underlies it.

Acquired curved hair is caused by fusion of multiple hair matrix cells

Background“Curved hair” caused by acquired factors is considered to have adverse cosmetic effects, but the detailed mechanism behind curved hair remains obscure. ObjectiveWe attempted to clarify the causes of curved hair that appeared to have occurred via acquired factors. MethodsOuter root sheath cells (ORSC) isolated from plucked human hair follicles were used to evaluate the expression of type IV collagen. Straight and curved hairs with hair follicle tissue attached were also collected from the same individuals and subjected to morphological, immunohistochemical, and gene expression analyses. ResultsThe amount of type IV collagen increased upon inducing endoplasmic reticulum stress in ORSC. Meanwhile, in curved hair follicle tissue, the gene expression of type IV collagen decreased. In addition, the curved hair follicle tissue obtained from participants in their 30 s to 50 s had distorted shapes compared with that of straight hair from the same individuals. It was also observed that hair matrix cells based on multiple hair germs fused to eventually form a single hair follicle and hair shaft. In curved hair follicle tissue, KRT71 protein, a marker of inner root sheath differentiation, was unevenly distributed and there was elevated expression of Dickkopf-1 (DKK1) protein, an inhibitor of the Wnt signaling pathway. ConclusionOur study revealed the fusion of hair matrix cells during hair follicle regeneration as a cause of acquired curved hair. We consider that such fusion causes hair follicle tissue to abnormally differentiate, resulting in asymmetric hair follicle shapes and curved hair.

Biomimetic biphasic microsphere preparation based on the thermodynamic incompatibility of glycosaminoglycan with gelatin methacrylate for hair regeneration

Hair follicle (HF) tissue engineering is promising for hair loss treatment especially for androgenetic alopecia. Physiologically, the initiation of HF morphogenesis relies on the interactions between hair germ mesenchymal and epithelial layers. To simulate this intricate process, in this study, a co-flowing microfluidic-assisted technology was developed to produce dual aqueous microdroplets capturing growth factors and double-layer cells for subsequent use in hair regeneration. Microspheres, called G/HAD, were generated using glycosaminoglycan-based photo-crosslinkable biological macromolecule (HAD) shells and gelatin methacrylate (GelMA) cores to enclose mesenchymal cells (MSCs) and mouse epidermal cells (EPCs). The findings indicated that the glycosaminoglycan-based HAD shells display thermodynamic incompatibility with GelMA cores, resulting in the aqueous phase separation of G/HAD cell spheres. These G/HAD microspheres exhibited favorable characteristics, including sustained growth factor release and wet adhesion properties. After transplantation into the dorsal skin of BALB/c nude mice, G/HAD cell microspheres efficiently induced the regeneration of HFs. This approach enables the mass production of approximately 250 dual-layer microspheres per minute. Thus, this dual-layer microsphere fabrication method holds great potential in improving current hair regeneration techniques and can also be combined with other tissue engineering techniques for various regenerative purposes.

Activation of the integrated stress response in human hair follicles.

Unravelling how energy metabolism and stress responses are regulated in human scalp hair follicles could reveal novel insights into the controls of hair growth and provide new targets to manage hair loss disorders. The Mitochondrial Pyruvate Carrier (MPC) imports pyruvate, produced via glycolysis, into the mitochondria, fuelling the TCA cycle. Previous work has shown that MPC inhibition promotes lactate generation, which activates murine epithelial hair follicle stem cells (eHFSCs). However, by pharmacologically targeting the MPC in short-term human hair follicle ex vivo organ culture experiments using UK-5099, we induced metabolic stress-responsive proliferative arrest throughout the human hair follicle epithelium, including within Keratin 15+ eHFSCs. Through transcriptomics, MPC inhibition was shown to promote a gene expression signature indicative of disrupted FGF, IGF, TGFβ and WNT signalling, mitochondrial dysfunction, and activation of the integrated stress response (ISR), which can arrest cell cycle progression. The ISR, mediated by the transcription factor ATF4, is activated by stressors including amino acid deprivation and ER stress, consistent with MPC inhibition within our model. Using RNAScope, we confirmed the upregulation of both ATF4 and the highly upregulated ATF4-target gene ADM2 on human hair follicle tissue sections in situ. Moreover, treatment with the ISR inhibitor ISRIB attenuated both the upregulation of ADM2 and the proliferative block imposed via MPC inhibition. Together, this work reveals how the human hair follicle, as a complex and metabolically active human tissue system, can dynamically adapt to metabolic stress.

Soy protein/β-chitin sponge-like scaffolds laden with human mesenchymal stromal cells from hair follicle or adipose tissue promote diabetic chronic wound healing

Chronic wounds are a worldwide problem that affect >40 million people every year. The constant inflammatory status accompanied by prolonged bacterial infections reduce patient's quality of life and life expectancy drastically. An important cell type involved in the wound healing process are mesenchymal stromal cells (MSCs) due to their long-term demonstrated immunomodulatory and pro-regenerative capacity. Thus, in this work, we leveraged and compared the therapeutic properties of MSCs derived from both adipose tissue and hair follicle, which we combined with sponge-like scaffolds (SLS) made of valorized soy protein and β-chitin. In this regard, the combination of these cells with biomaterials permitted us to obtain a multifunctional therapy that allowed high cell retention and growing rates while maintaining adequate cell-viability for several days. Furthermore, this combined therapy demonstrated to increase fibroblasts and keratinocytes migration, promote human umbilical vein endothelial cells angiogenesis and protect fibroblasts from highly proteolytic environments. Finally, this combined therapy demonstrated to be highly effective in reducing wound healing time in vivo with only one treatment change during all the experimental procedure, also promoting a more functional and native-like healed skin.

Organoid‐Loaded Cryomicroneedles for Biomimic Hair Regeneration

AbstractOrganoids have attracted extensive attention in the field of hair follicle (HF) tissue engineering and regeneration. However, HF organoid implantation faces a number of difficulties, such as low viability ratios, invasive trauma, and complicated procedures. To overcome these issues, a convenient and minimally invasive delivery approach with high efficiency and cell viability is required. Here, HF organoid‐loaded methacrylated gelatin‐cryomicroneedles (GelMA‐cryoMNs) that are capable of efficient transdermal delivery and can maintain the viability of the embedded organoids are developed. The GelMA‐cryoMNs are fabricated by a stepwise cryogenic molding process using a balanced ratio of cryopreservation agents and GelMA hydrogel. They can be inserted easily into porcine skin and melted without leaving residue after delivering the organoids. In vitro and in vivo, organoids delivered by the cryoMNs retain cell viability, self‐assembly, and differentiation ability. In mice, HF organoid‐loaded GelMA‐cryoMNs are delivered to the superficial dermis, resulting in subsequent HF development and the formation of an array of biomimetic hair tufts that broke through the skin surface. A promising strategy is provided here for biomimetic hair neogeneration that benefits from minimal invasion, low cost, and simple fabrication. The GelMA‐cryoMNs developed here could also have broader applications in tissue engineering and organ regeneration.

A novel antibacterial hydrogel based on thiolated ovalbumin/gelatin with silver ions to promote wound healing in mice

Hydrogels could be used as wound dressings, but most protein-based hydrogels lack anti-bacterial effects. Here, we successfully prepared a silver ion cross-linked thiolated protein hydrogel (thiolated Ovalbumin and Gelatin, O3G7). The wound photographs showed that the healing rate (96.23 %) of hydrogel-treated mice was higher than the control group. Meanwhile, the hydrogel increased the granulation tissue's total protein content. Furthermore, it significantly increased the collagen content, consistent with the results of Masson's trichrome (MT) staining and immunohistochemical analysis of type I collagen (ColI). The results of hematoxylin and eosin (H&E) staining showed the growth and proliferation of inflammatory cells, granulation tissue, fibroblasts, blood vessels and hair follicles in acute wounds. O3G7 hydrogel had fewer inflammatory cells and more neovascularization, and hair follicle tissue and intact epidermis could be observed. The results of immunofluorescence and immunohistochemistry showed that the O3G7 group reduced the expression of tumor necrosis factor (TNF)-α (56.87 % of the control group) and upregulated the expression of transforming growth factor (TGF)-β (1.29 times of the control group). These results suggest that O3G7 hydrogel significantly affects the healing of acute wounds. This study demonstrates that hydrogels prepared from food-derived proteins will be promising and bio-safe candidates in bioengineering.

The Effect of Lavandula stoechas on Wound Healing in an Experimental Diabetes Model.

Diabetic foot is a consequential and dangerous complication of diabetes, contributing to decreased quality of life, escalated hospitalizations, and increased mortality rates. Using an experimental model of diabetes, this study aims to investigate the effect of Lavandula stoechas on wound healing. A total of 35 albino Wistar rats, 250-350 grams in weight, were used. The rats were divided into five groups, seven rats in each group. Of these, 21 rats were induced with 50 mg/kg streptozotocin (STZ) to mimic the diabetic condition. Additionally, 14 rats remained non-diabetic and served as the control group. The diabetic rats were further divided into three subgroups. The non-diabetic group was split into two subgroups based on the dressing materials used (allicin, physiological serum, and control). Wound dimensions were assessed on Days 0, 7, 14, and 21. Biopsies were taken from the wound sites at the same time. There were significant differences between groups on Days 7, 14, and 21. The percentage of healing was highest in the Lavandula Stoechas group on Days 7, 14, and 21. Microscopic examination of the biopsies supported accelerated wound healing on Days 7 and 14. Reduced mononuclear cell density and increased hair follicle and adipose tissue development were observed in the DM (diabetes mellitus)-Lavandula Stoechas group on Day 7. On Day 14, the DM-Lavandula Stoechas group increased collagen levels and hair follicles. Similarly, the non-DM-Lavandula Stoechas group showed reduced bullae, dermal edema, and intraepithelial edema on Day 7. This was followed by increased fibroblast levels on Day 14. In conclusion, this study provides compelling evidence for the potential of Lavandula stoechas extract in the enhancement of diabetic wound healing. The multiple interactions revealed here highlight the need for further investigation into the underlying mechanisms. A cost-effective use of Lavandula stoechas opens up promising prospects in managing diabetic foot healing. This warrants additional research and clinical translation.

Treatment of androgenetic alopecia by exosomes secreted from hair papilla cells and the intervention effect of LTF.

Androgenetic alopecia (AGA) is the most common cause of chronic progressive hair loss in men, and AGA has a severe negative impact on the quality of life and physical and mental health of patients. Four female C57BL/6 mice were isolated from DP cells in culture (≤4 generations) after stimulation of DPC proliferation by herbal concentrations obtained by the CCK-8 method, and exosomes were isolated by differential centrifugation at low temperature. Testosterone propionate and topical hair removal treatments were used together to establish the C57BL/6 mouse AGA model, which was treated with LTF, 5% minoxidil, and LTF-DPC-EXO, respectively. ELISA was used to detect serum hormone levels, in vivo tracing was used to observe dynamic changes in exosomes, H&E staining showed changes in mouse hair follicle tissue, and (q) RT-PCR and WB were used to detect dorsal skin VEGF, AKT1, and CASP3 expression in dorsal skin tissues. Hair regeneration was significant in the LTF group, minoxidil group, and LTF-DPC-EXO group mice, and the hair growth was only seen in the local skin in the model group. The hormone T in all treatment groups was lower than that in the model group, and e2 was higher than that in the model group. (q) RT-PCR and western blot showed that VEGF and AKT1 expressions were upregulated and Caspase3 expression was downregulated in the skin sections of mice in the treatment groups. DPC-EXO obtained through LTF may activate AKT1 and VEGF in the PI3K/AKT signaling pathway to inhibit CASP3, thereby protecting DPC to restore the hair growth.

Microenvironmental reprogramming of human dermal papilla cells for hair follicle tissue engineering.

The restoration of hair-inductive potential in human dermal papilla cells (hDPCs) is a tremendous challenge for hair regeneration. Much of the research thus far has indicated that three-dimensional (3-D) culture shows improved efficacy in hair follicle (HF) neogenesis. However, mature HF cannot regenerate in an incomplete microenvironment. This study developed an optimized 3-D co-culture system to restore the hair-inductive characteristics of hDPCs by mimicking the in-vivo microenvironment. As a result, Matrigel-encapsulated hDPCs spontaneously formed into hDPC aggregates (hDPAs), which exhibited better activity, higher proliferation rates, and less apoptosis and hypoxia than the ultra-low attachment culture. Interestingly, the co-culture with the hair matrix cells and dermal sheath cup cells further enhanced the expression of hair regeneration-related genes of hDPAs compared to conditioned medium and improved mature HF induction. In addition, these hDPAs with higher hair inductivity could be produced on a large scale and easily separated for gene expression detection. Finally, the mRNA sequencing, PCR, and WB results showed that the co-culture biomimetic microenvironment stimulated the canonical Wnt signaling pathway and inhibited the BMP signaling pathway. Thus, this co-culture system will provide a reliable platform that allows high-throughput culture, testing, and harvesting of hDPAs for HF tissue engineering. STATEMENT OF SIGNIFICANCE: Extensive hair loss continues to be difficult to treat and causes significant patient morbidity. Hair follicle (HF) tissue engineering may seem to be a way out. However, the absence of the in-vivo microenvironment fails to regenerate mature hairs. This study systematically described a biomimetic co-culture approach to generate better quality human dermal papilla cell aggregates (hDPAs) with improved hair inductive properties, which can be further used for HF tissue engineering. The hDPC microenvironment was reprogrammed through the controllable formation of self-assembled organoids in Matrigel and the tri-culture with hair matrix cells and dermal sheath cup cells. This work indicates that the production of hDPAs could be readily scaled, in theory for large-scale assays, analyses, or therapeutic applications.

P19 Effects of rumen-passed methionine on rumen tissue, microbiota, fetal fat, and hair follicle tissue development in pregnant ewes

P19 Effects of rumen-passed methionine on rumen tissue, microbiota, fetal fat, and hair follicle tissue development in pregnant ewes

Evaluation of the therapeutic effects of AGA drugs by measuring finasteride, dutasteride, and dihydrotestosterone in hair

BackgroundAndrogenetic alopecia (AGA) is treated by 5α-reductase inhibitors (5ARI) such as finasteride and dutasteride, which are widely used as therapeutic agents. However, their pharmacokinetics in target organs (scalp and hair follicles) have not yet been investigated. PurposeTo confirm the effective action of finasteride and dutasteride in the hair follicle tissues, we developed a method to measure these concentrations in hair. ResultsCompared to the non-detection (N.D.) group, the dihydrotestosterone (DHT) concentrations decreased significantly in both the finasteride and dutasteride groups. The dutasteride group showed significantly lower DHT concentrations among all groups. ConclusionsMeasurement of finasteride, dutasteride, and DHT concentrations in hair would aid in evaluating the drug pharmacokinetics and its therapeutic effects on AGA patients.

Ginsenoside CK inhibits androgenetic alopecia by regulating Wnt/β‐catenin and p53 signaling pathways in AGA mice

AbstractAndrogenetic alopecia (AGA) is one of the most common chronic skin diseases caused by the destruction of androgens in the body. It is caused by the excessive deposition of dihydrotestosterone around the hair follicle, resulting in hair follicle atrophy and hair cell apoptosis. It causes great anxiety and psychological distress to patients and affects sexual function in severe cases. As traditional Chinese herbs, ginsenosides have been proven to possess various pharmacological activities. Ginsenoside CK is one of the main ginsenosides, but its role and molecular mechanism in treating AGA remain unclear. Here, we found that ginsenoside CK intervention significantly reduced back hair loss in AGA mice, improved sexual organ damage and hair follicle cell apoptosis, and promoted hair growth in AGA mice. Ginsenoside CK treatment inhibited p53 expression, reduced the apoptosis of hair follicle cells induced by hormone deposition, activated the Wnt/β‐catenin cell proliferation signaling pathway, increased the level of vascular endothelial growth factor, promoted cell proliferation, and improved the atrophy of hair follicle tissue. Ginsenoside CK treatment also reduced testosterone levels in AGA mice, improved testicular tissue inflammation, and restored normal hormone metabolism in AGA mice. Our results indicated that ginsenoside CK reduced hair follicle cell apoptosis, promoted proliferation and development, and prolonged the hair growth cycle by regulating the Wnt and p53 signaling pathways, indicating the potential value of ginsenoside CK as a natural therapeutic agent for AGA.

Gene expression changes reveal the impact of the space environment on the skin of International Space Station astronauts.

The various types of ionizing radiation and altered gravity in the space environment present a risk to humans during space missions. Changes in the space environment lead to skin diseases, affecting the status of the aviators to fly. Therefore, it is important to explore the molecular-level changes in the skin during space missions. Bioinformatics analysis of gene arrays from hair follicle tissue of 10 astronauts was performed to explore changes in gene expression before, during and after space missions. First, STEM (Short Time-series Expression Miner) software was used to identify the expression patterns of hair follicle genes of astronauts pre-, in- and postflight. Gene Ontology Enrichment Analysis was then performed to explore the gene functions within the module. Protein-protein interaction network analysis was performed on skin-related genes. The transcriptional regulatory network within the module was constructed using the TRRUST database. The circadian rhythm-related genes within the module were screened using the MSigDB (Molecular Signatures Database). Based on differential expression analysis between the two groups, there were 327 differentially expressed genes after the astronauts entered space compared with preflight, and only 54 differentially expressed genes after returning to Earth. This outcome suggests that the expression of most genes can be recovered on return to the ground, but there are a small number of genes whose expression cannot be recovered in a short period of time. Based on time series analysis, 311 genes showed increased expression on entry into space and decreased expression on return to Earth. The genes of this expression pattern were associated with skin development, keratinocyte differentiation and cornification. Ten hub genes were identified as skin-related genes within the module, as well as nine transcription factors and three circadian genes. One hundred and seventy-nine genes decreased in expression after entry into space and increased on return to Earth. By reviewing the literature, we found that four of the genes, CSCD2, HP, CXCR1 and SSTR4, are associated with skin diseases. Through bioinformatics analysis, we found that the space environment affects skin keratinocyte differentiation, leading to skin barrier damage and inflammatory responses, and that this effect was decreased after return to Earth.

Bioabsorbable nano-micelle hybridized hydrogel scaffold prevents postoperative melanoma recurrence.

The residual and scattered small tumor tissue or cells after surgery are the main reason for tumor recurrence. Chemotherapy has a powerful ability to eradicate tumors but always accompanied by serious side effects. In this work, tissue-affinity mercapto gelatin (GelS) and dopamine-modified hyaluronic acid (HAD) were employed to fabricate a hybridized cross-linked hydrogel scaffold (HG) by multiple chemical reactions, which could integrate the doxorubicin (DOX) loaded reduction-responsive nano-micelle (PP/DOX) into this scaffold via click reaction to obtain the bioabsorbable nano-micelle hybridized hydrogel scaffold (HGMP). With the degradation of HGMP, PP/DOX was slowly released and formed targeted PP/DOX with degraded gelatin fragments as target molecules, which increased the intracellular accumulation, and inhibited the aggregation of B16F10 cells in vitro. In mouse models, HGMP absorbed the scattered B16F10 cells and released targeted PP/DOX to suppress tumorigenesis. For another, implantation of HGMP at the surgical site reduced the recurrence rate of postoperative melanoma and inhibited the growth of recurrent tumors. Meanwhile, HGMP significantly relieved the damage of free DOX to hair follicle tissue. This bioabsorbable nano-micelle hybridized hydrogel scaffold provided a valuable strategy for adjuvant therapy after tumor surgery.

Skin-on-a-chip strategies for human hair follicle regeneration.

The number of hair loss patients increases every year, and hair loss treatment has several limitations, so research on hair is attracting attention recently. However, most current hair follicle research models are limited by their inability to replicate several key functions of the hair follicle microenvironment. To complement this, an in vitro culture system similar to the in vivo environment must be constructed. It is necessary to develop a hair-on-a-chip that implements a fully functional hair follicle model by reproducing the main characteristics of hair follicle morphogenesis and cycle. In this review, we summarize the gradation of hair follicle morphogenesis and the roles and mechanisms of molecular signals involved in the hair follicle cycle. In addition, we discuss research results of various in vitro organoid products and organ-on-a-chip-based hair follicle tissue chips for the treatment of alopecia and present future research and development directions.

Scalable and high-throughput production of an injectable platelet-rich plasma (PRP)/cell-laden microcarrier/hydrogel composite system for hair follicle tissue engineering

BackgroundTissue engineering of hair follicles (HFs) has enormous potential for hair loss treatment. However, certain challenges remain, including weakening of the dermal papilla cell (DPC) viability, proliferation, and HF inducibility, as well as the associated inefficient and tedious preparation process required to generate extracellular matrix (ECM)-mimicking substrates for biomolecules or cells. Herein, we utilized gelatin methacryloyl (GelMA) and chitosan hydrogels to prepare scalable, monodispersed, and diameter-controllable interpenetrating network GelMA/chitosan-microcarriers (IGMs) loaded with platelet-rich plasma (PRP) and seeded with DPCs, on a high-throughput microfluidic chip.ResultsThe ECM-mimicking hydrogels used for IGMs exhibited surface nano-topography and high porosity. Mass production of IGMs with distinct and precise diameters was achieved by adjusting the oil and aqueous phase flow rate ratio. Moreover, IGMs exhibited appropriate swelling and sustained growth factor release to facilitate a relatively long hair growth phase. DPCs seeded on PRP-loaded IGMs exhibited good viability (> 90%), adhesion, spreading, and proliferative properties (1.2-fold greater than control group). Importantly, PRP-loaded IGMs presented a higher hair inducibility of DPCs in vitro compared to the control and IGMs group (p < 0.05). Furthermore, DPC/PRP-laden IGMs were effectively mixed with epidermal cell (EPC)-laden GelMA to form a PRP-loaded DPC/EPC co-cultured hydrogel system (DECHS), which was subcutaneously injected into the hypodermis of nude mice. The PRP-loaded DECHS generated significantly more HFs (~ 35 per site) and novel vessels (~ 12 per site) than the other groups (p < 0.05 for each).ConclusionTaken together, these results illustrate that, based on high-throughput microfluidics, we obtained scalable and controllable production of ECM-mimicking IGMs and DECHS, which simulate an effective micro- and macro-environment to promote DPC bioactivity and hair regeneration, thus representing a potential new strategy for HF tissue engineering.

Hairy nodule: A rare case report

Trichofolliculoma represents an uncommon hamartoma of hair follicle tissue typically occurring on face of adults. Trichofolliculoma represents abortive differentiation of pluripotent skin cells toward hair Follicles. Trichofolliculoma although classified under hair follicle tumors, essentially are benign hamartomas of the hair follicle. They are rare and usually present as solitary lesions on the face often with a tiny tuft of fine white hairs arising from the surface.We present a case of 40 year old female with a small growth on face from last 6 year, it is asymptomatic and non progressive in nature, on local examination the papule was skin colored, firm , non-tender, the systemic examination was noncontributory and radiological examination revealed no bony destruction or formation of sinus tract clinical diagnosis is thought to be benign adnexal lesion, excisional biopsy was done for the lesion, On histopathological examination it was confirmed as trichofolliculoma, so, the final diagnosis of trichofolliculoma was made, and no recurrence was noted during the follow‑up of 1 year.

Autoantigen Discovery in the Hair Loss Disorder, Alopecia Areata: Implication of Post-Translational Modifications.

Alopecia areata (AA) is a chronic, multifactorial, polygenic, and heterogeneous disorder affecting growing hair follicles in susceptible individuals, which results in a non-scarring and reversible hair loss with a highly unpredictable course. Despite very considerable research effort, the nature of the precipitating factor(s) responsible for initiating AA in any given hair follicle remains unclear, due largely to significant gaps in our knowledge of the precise sequence of the etiopathogenic events in this dermatosis. However, disease-related changes in the immune-competence of the lower growing hair follicle, together with an active immune response (humoral and cellular) to hair follicle-associated antigens, are key associated phenomena. Confirmation of the hair follicle antigen(s) implicated in AA disease onset has remained stubbornly elusive. While it may be considered somewhat philosophical by some, it is also unclear whether immune-mediated hair loss in AA results from a) an ectopic (i.e., in an abnormal location) immune response to native (unmodified) self-antigens expressed by the healthy hair follicle, b) a normal immune response against modified self-antigens (or neoantigens), or c) a normal immune response against self-antigens (modified/non-modified) that were not previously visible to the immune system (because they were conformationally-hidden or sequestered) but become exposed and presentable in an MHC-I/-II molecule-restricted manner. While some candidate hair follicle antigen target(s) in AA are beginning to emerge, with a potential role for trichohyalin, it is not yet clear whether this represents the initial and immunodominant antigenic focus in AA or is simply one of an expanding repertoire of exposed hair follicle tissue damage-associated antigens that are secondary to the disease. Confirmation of autoantigen identity is essential for our understanding of AA etiopathogenesis, and consequently for developing a more informed therapeutic strategy. Major strides have been made in autoantigen discovery in other autoimmune conditions. In particular, some of these conditions may provide insights into how post-translational modifications (e.g., citrullination, deamidation, etc.) of hair follicle-restricted proteins may increase their antigenicity and so help drive the anti-hair follicle immune attack in AA.