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The big question:
Is this another 2-5 year false promise with the eventual and likely turn around time of 15 years or what?Comment
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Honestly we would have to now, at what exact stage the clinical trials are at. Their funding, which has to be substantial if they enrolled 400 people for phase 1( if it is phase 1), and what is the clinical testing cycle for new drug on treatment in Taiwan.
But Jahodas methods are the end game, they are the "cure". So even if it ain't the full cure(22% gene expression in Jahoda/Christiano method) they at least started with clinical trials. If they improve the method the safety ahs already been proven, and if Lin's method ends up in upping the gene expression then thats it.Comment
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Back in 2009...
An assistant professor at National Taiwan University’s biomedical engineering institute has utilized tissue-engineering technology to offer new hope in the fight against baldness.
Professor Lin Sung-jan took 10 hair follicles from rodents and cultivated 8 to 10 million dermal papilla cells in vitro in 20 days. Using aggregates of between 3 and 5 million dermal papilla cells, he mixed these with rodent skin cells and transplanted them onto bare rodent skin, which sprouted hair.
Lin’s findings were published in the internationally renowned tissue-engineering journal, Biomedical Materials, and also earned him Academia Sinica’s 2009 Junior Researcher Award June 1. The award committee felt his use of biomedical materials to develop micro-tissues capable of insertion and verification via animal testing had value for clinical applications in inducing and facilitating hair follicle regeneration.
Discovering that dermal papilla cells function to send signals and implement instructions, Lin developed biomaterial that can assemble and produce such cells. He also developed a bio-reaction device for use in mass-producing micro-tissues to induce hair follicle regeneration.
Lin has also taken human hair follicles and conducted similar experiments, successfully growing hair on the skin of rodents. In future, he hopes to be able to control the size and color of hair grown.
“Hair that is too thick or thin will not do,” Lin said. “If hair color can be controlled, it will be possible to transplant white or even blond hair.”Comment
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Scalable production of controllable dermal papilla spheroids on PVA surfaces and the effects of spheroid size on hair follicle regeneration.:
Therapeutic strategy for hair regeneration: hair cycle activation, niche environment modulation, wound-induced follicle neogenesis, and stem cell engineering.
http://www.researchgate.net/publicat...ll_engineeringComment
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Macroenvironmental regulation of hair cycling and collective regeneration behavior
More articles on this site:
Comment
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Hey brother
yeah I managed to get my hands on ine of the papers but not all of them. Uploading them would be fantastic
Btw southern just posted some more studies. Is anyone able to maybe just copy paste the studies on here? This way we can have a great database of everything to do with this technique
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Also just for the record, this isn't Jahoda's culturing method. They're going about it in a completely dofferent way. I'll try and summarise it this weekend for everyone.
Btw, did anyone send them an email?Comment
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For those of you wanting to read their papers but can not access them, here's the key points in their 2008 study. If anyone is able to access their 2011 study, it would be really appreciated. I'm still trying to get my friends on another forum to track it down
__________________________________________________ ______________
Self-assembly of dermal papilla cells into inductive spheroidal microtissues on poly(ethylene-co-vinyl alcohol) membranes for hair follicle regeneration
Received 19 April 2008
Accepted 12 May 2008
Tai-Horng Young, Chiao-Yun Lee, Hsien-Ching Chiu, Chih-Jung Hsu, Sung-Jan Lin
Unlike other fields of tissue reconstruction, such as adipose tissue and cartilage reconstruction which involves only one type of cells, production of human HFs in vitro by inducing cultured epithelial cells into a complex HF mini-organ is very challenging. Though organ culture of excised HFs in vitro has been demonstrated, efficient neogenesis of human HFs in adult life in vitro has not been achieved.
Another approach for HF bioengineering is to generate environments that allow skin to simulate the complex HF morphogenic process in embryological stage. One particular subject regarding this is the dominant role of DP cells in guiding the non-follicular epidermis to develop into HF structures. During the initial stage of HF morphogenesis, DP cells self-aggregate in the dermis and play a vital role in guiding the epidermal placode to develop into follicular structures. It was initially demonstrated that freshly isolated DP can induce new HFs when it is properly placed in the skin in rodents. However, to generate a large number of new HFs, DP cells should be expanded in vitro. The in vitro expansion of DP cells was first achieved by Jahoda and Oliver. The same group and other researchers have also demonstrated that cultured DP cells also retain the ability of inducing new HFs when they are transplanted in close proximity to the epidermis.
Of note is that the ability of DP cells to induce new HFs is dependent on their intercellular organization. Physiologically, DP cells are aggregated in the hair bulb. When they are cultured in vitro on conventional culture plates, they show a tendency to aggregate. The HF induction activity is only preserved when they are transplanted to the subepidermal space as dense aggregates.
Therefore, neogenesis of HF can be achieved by transplanting cultured DP cells as dense multicellular aggregates or microtissues. However, high efficiency of DP expansion and HF neogenesis should be achieved before such procedures can be put into clinical applications.
In addition to the large number of new HFs required, HFs should also be regenerated with a natural density and spacing on the desired body surface. To solve the above-mentioned issues in HF engineering, we can employ a three-step approach:
1) First, DP cells are expanded in vitro. The method utilized should be able to expand a large number of DPs within an acceptable period.
2) Second, DP cells are cultivated into dense microtissues. Since thousands of DP microtissues are needed, the method used in this step is also a key to the efficiency of the entire process.
3) Lastly, DP cells are transplanted with desired spacing to regenerate HFs.
The expansion of DP cells has been demonstrated by explant culture on conventional culture plates. However, there is currently lack of an efficient method to cultivate DP cells into dense multicellular aggregates on a large scale for the purpose of HF engineering. A two-step rotation and floatation method has been employed to generate tissues with limited follicular differentiation by using single cells isolated from the lip skin of fetal rats, but the method is labor taking and cells from adult rats fail to aggregate into microtissues in this system.
We have shown that cells can self-assemble into dense spheroids on controlled biomaterial surfaces [27–29]. Up to date, the interaction of DP with biomaterials has been rarely examined and the ability of controlled biomaterial surfaces to enhance the selfassembly of DP cells into microtissues has not been tested. Though self-aggregation of DP cells is essential for HF morphogenesis and physiology, the detailed dynamics and mechanism regarding this self-assembling behavior have not been investigated in detail. Establishing an in vitro model for DP self-aggregation may contribute to researches in this field.
In this work, we describe the behavior of DP cells on poly- (ethylene-co-vinyl alcohol) (EVAL) membrane surface, especially the spontaneous growth of DP cells into spheroidal microtissues that are able to induce new HFs. This self-aggregation is associated with a higher local cell density, relatively weakened cell–substrate adhesivity and enhanced cell migration on EVAL. Our results suggest that an adhesive biomaterial is suitable for quick expansion of DP cells and a relatively low-adhesive surface is required for DP aggregation. In addition to HF engineering, this system can also help to analyze the self-aggregation behavior of DP cells.
Materials and methods
1) Poly(ethylene-co-vinyl alcohol) (EVAL) membrane preparation: Commercially available EVAL (E105A, Kuraray, Japan, 56 mol% vinyl alcohol) was
used in this study. EVAL membrane with a dense structure was prepared as previously described [30,31]. The EVAL solution was prepared by dissolving EVAL in dimethyl sulfoxide (Merck, Germany) to a final concentration of 20 wt.% at 60 C in a water bath.
2) Cell culture: Vibrissal HFs were isolated by scissors and forceps from skin specimens fromcheeks ofWistar rats in Dulbecco’s Modified Eagle’s Medium (DMEM) (Gibco) supplemented with 1-fold concentrated Antibiotic–Antimycotic
*NOTE: this was a study in rats...
Results
a) The formation of multicellular DP microtissues on EVAL membranes at higher seeding cell number
After 3 days in culture, formation of multiple dense DP microtissues can be observed on EVAL.
We characterize the number and size distribution of the DP microtissues formed on EVAL after 5 days in culture (Table 1). Approximately, the diameter of the microtissues formed on EVAL on day 5 can vary from tens of mm to about 300 mm. Since the diameters of the freshly isolated DPs of Wistar rats are about 100– 200 mm, microtissues with an average diameter larger than 125 mm are calculated. The number of microtissues increases as the seeding number is increased. At the seeding number of 160,000, the diameter of the microtissues is mainly within the range of 125– 150 mm. Overall, about 47 microtissues (diameter> 125 mm) can be obtained on an EVAL surface of 1.9 cm2 with a single seeding of 160,000 DP cells.
The scanning electron micrograph shows that the microtissue is a spheroidal structure (Fig. 2). This structure is similar to DPs in vivo, i.e. aggregated as a compact multicellular mass.
High viability of cells in DP microtissues and the transformable cell morphology on different substratum
After the microtissues are reseeded on TCPS surface, the cells are able to grow and migrate out of the microtissues on day 1 (Fig. 3). The microtissues start to disintegrate on day 2 and further grow into confluent flat cells on day 8 (Fig. 3). This observation indicates that the cells in DP microtissues are viable and the morphologies of DP cells are transformable on different culture substratum. We then quantify the cell viability and reveal that the cell viability in DP microtissues obtained on EVAL is different from that in DP spheroids generated by hanging drop method [24]. The cell viability in DP microtissues on EVAL is much higher than that in DP spheroids generated by hanging drop method (mean viability is 96.39 0.09 and 53.3 3.3%, respectively; p-value < 0.001). The result suggests that the viability of cells in microtissues can be affected by the method employed to generate microtissues.
DP microtissues are able to induce new HFs
We then ask whether DP microtissues generated on EVAL retain the HF induction activity. When DP microtissues are mixed with newborn mouse epidermal cells and injected into the hypodermis of nude mice in a patch assay, similar to positive controls (data not shown), they are able to induce new HFs (Fig. 4). In the negative controls, no HF is revealed (data not shown). The results show that, in addition to preserving molecular markers, DP microtissues generated on EVAL still retain HF induction ability, the signature function of DP cells.
Conclusion
Self-assembly of DP cells into spheroidal inductive microtissues can be facilitated when cells are seeded at appropriate densities on EVAL surface. Formation of DP microtissue is associated with enhanced cell migration and lower cell–substrate adhesivity on EVAL surface. On the contrary, a more adherent surface, such as TCPS, allows faster DP cell expansion in a monolayered morphology.
Our results suggest that, for efficient large-scale production of DP microtissues for HF engineering, cells can be first expanded on more adhesive surface and then transferred to EVAL to facilitate the self-assembly into microtissues.We also characterize the dynamics of DP microtissue formation on EVAL. After cells attach to EVAL, active migration, intercellular collision and intercellular aggregation lead to microtissue formation. Our system is of potential to be applied to HF engineering and the investigation of DP selfaggregation.Comment
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I have a feeling EVAL is not going into our scalp. I think they are only culturing the DP cells on it! Once in a spheroid microtissue structure, they are removed from the EVAL and simply implanted. Did anyone get that vibe reading their paper? We really need access to the second paper.Comment
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Thanks Desmond! I haven't sent the email yet. Not being a native english speaker, I guess I'm not the best candidate to do the job, but I guess I'll give it a try.
For those of you wanting to read their papers but can not access them, here's the key points in their 2008 study. If anyone is able to access their 2011 study, it would be really appreciated. I'm still trying to get my friends on another forum to track it down
__________________________________________________ ______________
Self-assembly of dermal papilla cells into inductive spheroidal microtissues on poly(ethylene-co-vinyl alcohol) membranes for hair follicle regeneration
Received 19 April 2008
Accepted 12 May 2008
Tai-Horng Young, Chiao-Yun Lee, Hsien-Ching Chiu, Chih-Jung Hsu, Sung-Jan Lin
Unlike other fields of tissue reconstruction, such as adipose tissue and cartilage reconstruction which involves only one type of cells, production of human HFs in vitro by inducing cultured epithelial cells into a complex HF mini-organ is very challenging. Though organ culture of excised HFs in vitro has been demonstrated, efficient neogenesis of human HFs in adult life in vitro has not been achieved.
Another approach for HF bioengineering is to generate environments that allow skin to simulate the complex HF morphogenic process in embryological stage. One particular subject regarding this is the dominant role of DP cells in guiding the non-follicular epidermis to develop into HF structures. During the initial stage of HF morphogenesis, DP cells self-aggregate in the dermis and play a vital role in guiding the epidermal placode to develop into follicular structures. It was initially demonstrated that freshly isolated DP can induce new HFs when it is properly placed in the skin in rodents. However, to generate a large number of new HFs, DP cells should be expanded in vitro. The in vitro expansion of DP cells was first achieved by Jahoda and Oliver. The same group and other researchers have also demonstrated that cultured DP cells also retain the ability of inducing new HFs when they are transplanted in close proximity to the epidermis.
Of note is that the ability of DP cells to induce new HFs is dependent on their intercellular organization. Physiologically, DP cells are aggregated in the hair bulb. When they are cultured in vitro on conventional culture plates, they show a tendency to aggregate. The HF induction activity is only preserved when they are transplanted to the subepidermal space as dense aggregates.
Therefore, neogenesis of HF can be achieved by transplanting cultured DP cells as dense multicellular aggregates or microtissues. However, high efficiency of DP expansion and HF neogenesis should be achieved before such procedures can be put into clinical applications.
In addition to the large number of new HFs required, HFs should also be regenerated with a natural density and spacing on the desired body surface. To solve the above-mentioned issues in HF engineering, we can employ a three-step approach:
1) First, DP cells are expanded in vitro. The method utilized should be able to expand a large number of DPs within an acceptable period.
2) Second, DP cells are cultivated into dense microtissues. Since thousands of DP microtissues are needed, the method used in this step is also a key to the efficiency of the entire process.
3) Lastly, DP cells are transplanted with desired spacing to regenerate HFs.
The expansion of DP cells has been demonstrated by explant culture on conventional culture plates. However, there is currently lack of an efficient method to cultivate DP cells into dense multicellular aggregates on a large scale for the purpose of HF engineering. A two-step rotation and floatation method has been employed to generate tissues with limited follicular differentiation by using single cells isolated from the lip skin of fetal rats, but the method is labor taking and cells from adult rats fail to aggregate into microtissues in this system.
We have shown that cells can self-assemble into dense spheroids on controlled biomaterial surfaces [27–29]. Up to date, the interaction of DP with biomaterials has been rarely examined and the ability of controlled biomaterial surfaces to enhance the selfassembly of DP cells into microtissues has not been tested. Though self-aggregation of DP cells is essential for HF morphogenesis and physiology, the detailed dynamics and mechanism regarding this self-assembling behavior have not been investigated in detail. Establishing an in vitro model for DP self-aggregation may contribute to researches in this field.
In this work, we describe the behavior of DP cells on poly- (ethylene-co-vinyl alcohol) (EVAL) membrane surface, especially the spontaneous growth of DP cells into spheroidal microtissues that are able to induce new HFs. This self-aggregation is associated with a higher local cell density, relatively weakened cell–substrate adhesivity and enhanced cell migration on EVAL. Our results suggest that an adhesive biomaterial is suitable for quick expansion of DP cells and a relatively low-adhesive surface is required for DP aggregation. In addition to HF engineering, this system can also help to analyze the self-aggregation behavior of DP cells.
Materials and methods
1) Poly(ethylene-co-vinyl alcohol) (EVAL) membrane preparation: Commercially available EVAL (E105A, Kuraray, Japan, 56 mol% vinyl alcohol) was
used in this study. EVAL membrane with a dense structure was prepared as previously described [30,31]. The EVAL solution was prepared by dissolving EVAL in dimethyl sulfoxide (Merck, Germany) to a final concentration of 20 wt.% at 60 C in a water bath.
2) Cell culture: Vibrissal HFs were isolated by scissors and forceps from skin specimens fromcheeks ofWistar rats in Dulbecco’s Modified Eagle’s Medium (DMEM) (Gibco) supplemented with 1-fold concentrated Antibiotic–Antimycotic
*NOTE: this was a study in rats...
Results
a) The formation of multicellular DP microtissues on EVAL membranes at higher seeding cell number
After 3 days in culture, formation of multiple dense DP microtissues can be observed on EVAL.
We characterize the number and size distribution of the DP microtissues formed on EVAL after 5 days in culture (Table 1). Approximately, the diameter of the microtissues formed on EVAL on day 5 can vary from tens of mm to about 300 mm. Since the diameters of the freshly isolated DPs of Wistar rats are about 100– 200 mm, microtissues with an average diameter larger than 125 mm are calculated. The number of microtissues increases as the seeding number is increased. At the seeding number of 160,000, the diameter of the microtissues is mainly within the range of 125– 150 mm. Overall, about 47 microtissues (diameter> 125 mm) can be obtained on an EVAL surface of 1.9 cm2 with a single seeding of 160,000 DP cells.
The scanning electron micrograph shows that the microtissue is a spheroidal structure (Fig. 2). This structure is similar to DPs in vivo, i.e. aggregated as a compact multicellular mass.
High viability of cells in DP microtissues and the transformable cell morphology on different substratum
After the microtissues are reseeded on TCPS surface, the cells are able to grow and migrate out of the microtissues on day 1 (Fig. 3). The microtissues start to disintegrate on day 2 and further grow into confluent flat cells on day 8 (Fig. 3). This observation indicates that the cells in DP microtissues are viable and the morphologies of DP cells are transformable on different culture substratum. We then quantify the cell viability and reveal that the cell viability in DP microtissues obtained on EVAL is different from that in DP spheroids generated by hanging drop method [24]. The cell viability in DP microtissues on EVAL is much higher than that in DP spheroids generated by hanging drop method (mean viability is 96.39 0.09 and 53.3 3.3%, respectively; p-value < 0.001). The result suggests that the viability of cells in microtissues can be affected by the method employed to generate microtissues.
DP microtissues are able to induce new HFs
We then ask whether DP microtissues generated on EVAL retain the HF induction activity. When DP microtissues are mixed with newborn mouse epidermal cells and injected into the hypodermis of nude mice in a patch assay, similar to positive controls (data not shown), they are able to induce new HFs (Fig. 4). In the negative controls, no HF is revealed (data not shown). The results show that, in addition to preserving molecular markers, DP microtissues generated on EVAL still retain HF induction ability, the signature function of DP cells.
Conclusion
Self-assembly of DP cells into spheroidal inductive microtissues can be facilitated when cells are seeded at appropriate densities on EVAL surface. Formation of DP microtissue is associated with enhanced cell migration and lower cell–substrate adhesivity on EVAL surface. On the contrary, a more adherent surface, such as TCPS, allows faster DP cell expansion in a monolayered morphology.
Our results suggest that, for efficient large-scale production of DP microtissues for HF engineering, cells can be first expanded on more adhesive surface and then transferred to EVAL to facilitate the self-assembly into microtissues.We also characterize the dynamics of DP microtissue formation on EVAL. After cells attach to EVAL, active migration, intercellular collision and intercellular aggregation lead to microtissue formation. Our system is of potential to be applied to HF engineering and the investigation of DP selfaggregation.Comment
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well that's really good news, esp. for everyone younger than 20. most of them likely won't need to deal with hair loss in serious stages anymore. but being a 25-year old I want them to hurry up a bit
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