Tissue Engineering Strategies for Human Hair Follicle Regeneration: How Far From a Hairy Goal?

This study found that the human placenta extracellular matrix hydrogel restored the hair-inductive capacity of high-passaged dermal papilla cells, enabling them to regenerate new hair follicles when co-grafted with mouse epidermal cells.

This study found that cultured mouse dermal papilla (mDP) cells can induce hair follicle neogenesis in de novo regenerated skin tissues grafted onto mice.

This study demonstrated that combining the Wnt/β-catenin activator CHIR99021 with 3D spheroid culture effectively enriched hair follicle formation in reconstituted human skin.

This study developed a method for generating germ-like tissues called bbHFGs, which efficiently promoted hair follicle formation in mice, potentially advancing hair regenerative medicine applications.

This study found that TSA restored the hair-inductive capacity of skin-derived precursors in mice by enhancing BMP gene expression and signaling through histone acetylation.

The authors conclude that optimizing hair shaft production and appearance may best be achieved by integrating biological, chemical, and physical intervention strategies.

This study demonstrated that enhancing human skin constructs with hair follicles through engineered cell organization and vascularization improved hair growth in immunodeficient mice, suggesting potential advances for treating alopecia and chronic wounds.

This review discusses the significant burden of disease and psychosocial implications associated with alopecia, highlighting its comorbidities and the impact on quality of life despite being viewed traditionally as an aesthetic concern, but reports no clinical results.

This review discusses the use of Dermal Papilla cells as in vitro models for studying hair growth modulators, emphasizing their role in aiding the development of new hair treatments, but reports no new clinical results.

This study found that using 3D dermal papilla spheroid models enhances extracellular matrix production and hair follicle marker expression, providing insights into hair follicle biology and potential for drug screening.

This study found that a cocktail of three proteins from embryonic skin can enable adult fibroblasts to regenerate hair follicles by altering gene expression and activating regenerative signaling pathways.

This study observed that dermal papilla cell aggregates showed increased viability and gene expression on softer 3D substrates, indicating the importance of substrate stiffness in cellular behavior.

This study demonstrated a method for large-scale preparation of self-sorted hair follicle germs in vitro, which successfully generated hair follicles when transplanted into the skin of nude mice.

This study found that newborn mouse skin organoids can robustly grow hair in vivo, while adult organoids require specific interventions to restore their hair-forming ability.

This study found that 5% activated platelet-rich plasma significantly improved cell proliferation and hair-inductive ability of dermal papilla cells in vitro, and promoted hair follicle formation in mice.

This study found that micro-niches within hair follicles create heterogeneity among stem cells and transit-amplifying cells, leading to specialized progenitors that control tissue morphogenesis and regeneration.

This study found that while extracellular matrix components like hyaluronic acid promoted larger organoid formation, other matrix components hindered hair follicle germ assembly in an in vitro model.

This study demonstrated that cultured epidermal stem cells and skin-derived precursors can regenerate functional hair follicles and sebaceous glands in both mice and adult humans, suggesting potential for bioengineered skin substitutes.

Researchers created a fully functional, bioengineered skin system with hair from stem cells that successfully integrated when transplanted into mice.

This research found that Foxc1 transcription factor and COL17A1 are critical in regulating quiescence and hair thinning in hair follicle stem cells, with aging-related DNA damage leading to hair loss.

This protocol describes a method for regenerating hair follicles using a bioengineering technique called the Organ Germ Method, but it reports no new clinical results.

This study observed that applying JAK-STAT pathway inhibitors to mouse and human skin led to rapid hair growth by inducing the anagen phase of hair follicles.

This article discusses the challenges and possible solutions in hair restoration surgery, focusing on donor hair availability, hair survival, and concealing surgical evidence, and reports no new clinical results.

This study identifies a bipotent stem cell in adult hair follicles that self-renews and contributes to dermal sheath and papilla cell populations, potentially aiding hair regrowth after injury, disease, or aging.

This article provides contact information for Bruce A. Morgan and features no new research findings.

In this study, researchers developed a method to differentiate human iPSCs into cells that can generate all lineages of hair follicles, potentially aiding treatments for hair loss and skin disorders.

This review examines the literature on the molecular and cellular makeup of the hair follicle niche and how it influences stem cell behavior during hair regeneration, but does not provide new experimental results.

This study found that altering cell culture conditions to form three-dimensional papilla spheroids can restore the ability of human dermal papilla cells to induce hair growth in adult skin.

This article reviews methods to enhance epithelial–mesenchymal interactions for hair follicle bioengineering but does not present new experimental results; it emphasizes optimizing combinations for successful regeneration.

This study found that both human and rat dermal papilla spheroids can induce hair follicle neogenesis, but larger spheroids increase inductivity without significantly affecting hair fiber diameter.

This review discusses mesenchymal–epithelial interactions in hair follicle development and cycling, highlighting recent insights without reporting new experimental results.

This study reports that hair regeneration in live mice involves spatially regulated stem cell divisions and requires mesenchymal interactions, observed in real-time using a novel non-invasive imaging method.

This study found that dermal Shh signaling regulates specific dermal papilla signatures essential for maintaining hair follicle development, suggesting that the Shh-Noggin signaling loop is crucial for hair morphogenesis.

This study demonstrated that bioengineered hair follicles reconstituted from embryonic skin cells and transplanted into hosts can restore physiological hair functions, suggesting potential applications for treating alopecia.

This study demonstrates the potential of using bioengineered follicles from adult tissue-derived stem cells for fully functional hair regeneration, illustrating possible applications in organ replacement therapy.

This study found that cultured human dermal papilla cells formed into three-dimensional spheres have an increased ability to induce hair follicles from mouse epidermal cells compared to two-dimensional cultures.

This study successfully recreated human hair follicles in vitro, which offers a potential advancement in hair regeneration and understanding the effects of drugs on hair follicles.

This study found that androgenetic alopecia may involve a defect in the conversion of hair follicle stem cells to progenitor cells, as demonstrated by a reduced presence of progenitor cells in bald scalp samples.

This study developed a method for expanding human dermal papilla cells in vitro while maintaining their ability to induce hair growth, advancing the potential for follicular cell implantation as a treatment for hair loss.

This review discusses the development and advances in studying trichogenic dermal cells for hair follicle morphogenesis, summarizing methods, bioassays, and molecular markers, but reports no new research findings.

This review discusses the shedding phase of the hair cycle, known as exogen, and reports no new findings while analyzing related processes like club fiber formation and release.

In this study, co-grafting human keratinocytes with murine dermal papilla-enriched cells produced hair follicle-like structures, but without regular hair formation, suggesting anomalous folliculogenesis.

This article reviews the stages and regulation of the hair cycle, highlighting molecular regulators involved, but it does not present new research findings.

This article reviews follicular melanogenesis, detailing how melanin synthesis and its regulation in hair follicles depend on a complex interplay of cellular and molecular mechanisms, but reports no new clinical findings.

This study suggests that stress negatively affects hair growth by inducing inflammation and early hair cycle transitions in mice, which might inform strategies for managing stress-related hair loss in humans.

This study demonstrated that clonal dermal papilla and dermal sheath cell lines from hair follicles can differentiate into lipid and bone cells, suggesting their potential as a stem cell source for tissue engineering.

This study found that dermal papilla and peribulbar dermal sheath cup cells in mice can both induce hair follicle formation, suggesting they may have similar functional roles in hair growth.

This review summarizes recent advances in understanding the molecular mechanisms of hair follicle formation and discusses potential future clinical applications for treating hair loss and skin tumors, but it reports no new clinical results.

This study found that the volume of a hair follicle's dermal papilla is strongly correlated with its size, primarily due to the number of cells it contains and the volume of extracellular matrix.

This study observed that human hair follicles were able to regenerate fiber-forming structures after the bulb was amputated and transplanted onto athymic mice, suggesting a general regenerative capacity.

This article describes the potential role of various growth factors and molecules in regulating mammalian hair follicle development but does not present new experimental results.