Έρευνα γονιδιακής θεραπείας - Recombinant DNA Gene Therapy

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Σπύρος

Μέλος του προσωπικού
στο στάδιο της έρευνας,με ενθαρρυντικά αποτελέσματα,βρίσκεται η θεραπεία της τριχόπτωσης σε γονιδιακό επίπεδο
βασίζεται στην τεχνική αναδημιουργίας DNA σε επίπεδο γονιδίου-υπευθύνου για την τριχοφυΐα/τριχόπτωση
το σημαντικό είναι ότι:
- η θεραπεία θα απευθύνεται σε όλους τους τύπους τριχόπτωσης
- η επιτυχία της θα είναι 100%
- παρόμοιες τεχνικές χρησιμοποιούνται ήδη για την θεραπεία του καρκίνου του δέρματος

I) Gene Therapy May Hold Cure To Baldness

CHICAGO (CNN) -- Researchers at the University of Chicago's Howard Hughes Medical Center have discovered a new approach to treat baldness -- gene therapy.

Scientists were able to successfully transform skin cells into hair follicles in lab mice through the introduction of a so-called messenger molecule containing the protein beta catenin.

"We've always been told that you're born with a fixed number of hair follicles and that you can never grow them again in adult life," said Angela Christiano of Columbia University. "This study would suggest we now we have the capability to do that."

Similar experiments on humans, however, are not likely in the near future. The scientists have created some very hairy lab mice, but still don't understand how to contain the hair follicle growth process.

"You can actually go too far and cause the cells to grow too much," said University of Chicago researcher Elaine Fuchs. She warned that unchecked cell growth could lead to the development of tumors.

"We still need to understand how this molecule is regulated inside the cell of the developing hair follicle to really take it to the level of clinical application," she added.

About 50 percent of men over 50 experience some type of baldness, although different types can affect women and children as well.


II) Researchers Find First Gene for Baldness

By Reuters
January 29, 1998

WASHINGTON — Researchers announced Thursday the discovery of a gene which causes a rare form of hair loss, and may eventually be used to treat other types of hair loss.

The new gene, appropriately called hairless, could regulate the human hair cycle, they reported in the journal Science, report on their study of a Pakistani family suffering from Alopecia Universalis, a condition which leaves the affected person with no hair, including no body hair or eyebrows.

"The discovery of this new gene gives us endless possibilities that may allow us to effectively treat hair loss and possibly baldness within the next five years,'' said study leader and dermatologist Angela Christiano of New York's Columbia-Presbyterian Medical Center.

"It is now within our reach to design ways to grow hair, remove hair, even dye hair genetically and, best yet, this can all be accomplished topically, reducing possible side-effects.''

"With the hairless gene, the real basis of hair loss can begin to be understood,'' Christiano said. "We can now look at the cause — the genes themselves — with the understanding that hormones are important but not primary.''

"Hair follicles, like all cells, have cycles. This finding is the first indication that we may be able to regulate that cycle, triggering the growth of new hair. It may be possible, for instance, to treat hair loss through gene therapy administered topically via the hair follicles.''

Companies have already been developing means to perform gene therapy, although None have yet proven universally successful. The major limitation to date has been the discovery of an actual gene that causes male pattern hair loss.

What is not known and what will not be reported in the media is whether or not this gene may actually lead to a hair loss cure. There are many genes that relate to hair. Alopecia Areata and Universalis are thought to be autoimmune disorders and not related to male pattern hair loss, so it is unknown whether this gene may eventually lead to a cure, but you have to have a first step.

III) Gene therapy might treat baldness - U.S. experts say

By Reuters
June 13, 1999
WASHINGTON, June 10 (Reuters) - It might be possible to use gene therapy to treat baldness, researchers said on Thursday.

A team at the University of Pennsylvania said they had managed to get growing human hairs to take up genetic material -- and said it had been easier than they expected.

So far they have only been able to turn hair blue. But they say the idea could be turned to growing hair someday.
to worry about transcribing errors, and he liked the speed with which he could assist a larger clientele. He was even reconfiguring his two popular Web sites so customers could periodically access their files. , said in a statement.

The idea behind gene therapy is to use genetic material to replace a faulty
gene, or to boost the efforts of genes. It is being tested in a range of
conditions from cancer to heart failure.

Cotsarelis's team thought they would try it for a range of hair loss, including alopecia areata, caused when the body's immune system mistakenly attacks the hair follicles.

``It often occurs in children and can be psychologically devastating,''
Cotsarelis, who reported his teams' findings to a meeting of the American
Society of Gene Therapy, said.

They have not tried to treat baldness just yet. Instead, they used a gene
coding for an enzyme known as beta galactosidase, which turns the hair
follicle blue.

They grafted pieces of human scalp to specially bred mice.

To deliver the genes they used liposomes, which are little spheres of fat-like substance which are easily absorbed into cells. And they used a simpler form of the genetic material called plasmid DNA.

"When we apply the preparation to the follicles, the liposomes bind to the
cell membrane and the DNA is released into the cell, quickly finding its
way to the nucleus,'' Cotsarelis said.

The next step would be to try this targeting a gene that affects hair growth.
But there is a problem. Scientists do not yet know which genes these are.

But they say the idea holds promise.

"This is an example of a very clever use of a vector to deliver a protein, if
it works,'' said Dr. James Wilson, president of the American Society of Gene Therapy.


IV) A Novel Method for Gene Transfer into Keratinocytes in Vivo

Sawamura et al (p. 195) show that the use of the hemagglutinating virus of Japan (HVJ) incorporated into liposomes is useful for in vivo gene transfer into normal and transformed keratinocytes. This method involves the entrapment of DNA and nuclear protein within liposomes and the use of HVJ to enhance liposome fusion with cell membranes, increasing the efficiency of gene transfer. This method has been used successfully for gene transfer in other cells and tissues, leading the investigators to ask whether this method might transfer genes effectively to epidermal keratinocytes in vivo. The authors introduced the beta-galactosidase gene into the skin of hairless rats by this method and detected enzyme activity in the keratinocytes of the treated skin. Transfer efficiency of the HVJ-liposome method was about five times higher than with the use of "naked" DNA. The authors also assessed the efficacy of the method for transfer of the thymidine kinase gene of herpes simplex virus, incorporation of which can cause inhibition of growth of squamous cell carcinoma cells incubated with ganciclovir. Growth of transfected tumor cells in the presence of ganciclovir was inhibited, indicating that the method was effective in this setting as well. These findings indicate that the HVJ-liposome method is suitable for gene transfer to keratinocytes in vivo as well as in vitro and could be useful in gene therapy.

Source: Journal of Investigative Dermatology

V) Topical Viral Vectors for Transfer of Genes to the Skin

The ability to transfer genes to the skin could be useful in many genetic diseases and non-heritable diseases and also in such problems such as wound healing. A major hurdle in gene delivery to the skin has been the relatively poor transduction efficiency observed with currently available methods of delivering the gene of interest to the target tissue. Glynis Scott and her colleagues (Lu et al, p. 803) show that either of two viral vectors applied topically to mouse skin, an adenovirus or a herpes simplex amplicon virus, result in extensive delivery of plasmid DNA to most layers of the epidermis. Topical application of the adenovirus vector resulted in expression of the reporter lacZ gene for up to 7 days, with minimal associated inflammation. Intra-amniotic injection of the adenovirus vector successfully transferred genes to fetal periderm. Since transferred genes have not yet been shown to persist in skin, the technique will not cause the transfected periderm to develop into an epidermis that continues to secrete a gene product permanently, but the method could be useful in delivering secreted gene products into the amniotic fluid. The amplicon herpes virus vector produced extensive tissue necrosis, which will probably limit its use as a viral delivery system. These results indicate that adenovirus vectors may be useful, for example, in a "gene cream" for delivery of genes to the skin.

VI) Why is Expression of Retroviral Genes Lost?: Importance in Gene Therapy

Retroviruses engineered to produce human proteins and then transduced into a wide variety of types of cells are part of a strategy for gene therapy. In epidermal keratinocytes, expression of a transgene introduced by a retroviral transduction is expressed in culture for long periods of time, but is not sustained in vivo. Fenjves et al (p. 576) used the blood clotting protein, factor IX, examine this issue. Human keratinocytes in culture were transduced with retroviruses containing cDNA for factor IX. The transduced cells, which expressed factor IX in culture, were grafted onto nude mice, and factor IX was measured in their serum. "Shut off" of the foreign protein was noted in vivo even though these same cells continued to secrete factor IX in culture. The authors showed that a "control" protein produced constitutively by the human keratinocytes, apolipoprotein E, was still present in the serum of the grafted mice beyond the time when factor IX was no longer detectable. Since the human cells were not lost, and since there was no block to secretion of protein by grafted cells, the authors suggest that the lack of sustained expression of the transgene is due to inactivation of the retroviral promoter in vivo. Understanding of the mechanism of this loss of expression is crucial for the future of gene therapy. The authors suggest, and the work of others suggests, that use of tissue-specific promoters, such as a promoter controlling production of a human epidermal protein, may help overcome this problem.

Source: Journal of Investigative Dermatology

VII) Evidence for a single gene effect causing polycystic ovaries and male pattern baldness.

Author
Carey AH; Chan KL; Short F; White D; Williamson R; Franks S
Address
Department of Obstetrics and Gynaecology, St Mary's Hospital Medical School, Imperial College of Science Technology and Medicine, London, UK.
Source
Clin Endocrinol (Oxf), 1993 Jun, 38:6, 653-8
Abstract
OBJECTIVE: Polycystic ovary syndrome is one of the most common endocrine disorders but its aetiology remains unknown. It is highly prevalent within families, suggesting a genetic basic for the syndrome, but the mode of inheritance is unclear. The purpose of this study was to determine the mode of inheritance of polycystic ovary syndrome, within the families of affected individuals, by classic segregation analysis. DESIGN: All first degree relatives of affected individuals were screened for the presence or absence of polycystic ovaries in post-menarchal-premenopausal women and early onset male pattern baldness (MPB) in the males. In extended pedigrees, assignment of affected status in post-menopausal women was made by consideration of the clinical history alone. PATIENTS: Fourteen women (probands), presenting with a variety of clinical symptoms, were identified sequentially as having polycystic ovaries (PCO) by ultrasound scan. They were examined in detail to determine their family structure, clinical and endocrine status. Ten families were found to have sufficient members for further study. MEASUREMENTS: All family members had their body mass index calculated, their degree of hirsutism assessed using the Ferriman and Gallwey score and serum levels of gonadotrophins (FSH and LH), testosterone, prolactin and 17 alpha-hydroxyprogesterone measured by radioimmunoassay. A careful reproductive history was taken for each woman and any menstrual disturbance was noted. Obese probands had their glucose and insulin response to a standard 75-g oral glucose tolerance test determined. Each male family member was also assessed for the degree and time of onset of balding. RESULTS: First degree female relatives of affected individuals had a 51% chance of being affected. Early onset male pattern baldness (MPB) was found to be an accurate phenotype for obligate male carriers. Each family showed autosomal dominant inheritance for PCO with greater than 90% penetrance. CONCLUSIONS: We postulate that PCO and male pattern baldness are caused by alleles of the same gene which affect androgen production or action. The different frequencies of PCO and male pattern baldness arise from differing thresholds for phenotypic expression in females and males respectively. The modifying effects of other genes is the most likely explanation of the somewhat variable phenotype.

VIII) A recent study in the Journal of Investigative Dermatology studied 828 healthy families comprising 3000 individuals. They studied both young, bald individuals as well as older, non-bald individuals and compared the genes controlling 5-alpha reductase activity (DHT production). It was found that the genes between all the individuals showed no differences. In other words, the genes that control DHT production in men are NOT the cause of male pattern baldness. Some have theorized recently that it could be that the genes for DHT production in balding men caused a higher production of DHT, thus causing baldness. This study shows that there is no overproduction of DHT, or if there is it is not caused by the genes that control DHT production (5-alpha reductase activity).

Another interesting finding of the study was that baldness did not follow a simple genetic inheritence pattern. The study suggests researching the possibility of multiple genes controlling hair loss.

Genetic analysis of male pattern baldness and the 5alpha-reductase genes.
Author
Ellis JA; Stebbing M; Harrap SB
Address
Department of Physiology, The University of Melbourne, Parkville, Victoria, Australia.
Source
J Invest Dermatol, 110(6):849-53 1998 Jun
Abstract
Genetic predisposition and androgen dependence are important characteristics of the common patterned loss of scalp hair known as male pattern baldness. The involvement of the 5alpha-reductase enzyme in male pattern baldness has been postulated due to its role in the metabolism of testosterone to dihydrotestosterone. There are two known isozymes of 5alpha-reductase. Type I has been predominantly localized to the skin and scalp. Type II, also present on the scalp, is the target of finasteride, a promising treatment for male pattern baldness. We conducted genetic association studies of the 5alpha-reductase enzyme genes (SRD5A1 on chromosome 5 and SRD5A2 on chromosome 2) using dimorphic intragenic restriction fragment length polymorphisms. From a population survey of 828 healthy families comprising 3000 individuals, we identified 58 young bald men (aged 18-30 y) and 114 older nonbald men (aged 50-70 y) for a case control comparison. No significant differences were found between cases and controls in allele, genotype, or haplotype frequencies for restriction fragment length polymorphisms of either gene. These findings suggest that the genes encoding the two 5alpha-reductase isoenzymes are not associated with male pattern baldness. Finally, no clear inheritance pattern of male pattern baldness was observed. The relatively strong concordance for baldness between fathers and sons in this study was not consistent with a simple Mendelian autosomal dominant inheritance. A polygenic etiology should be considered.
 

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Παναγιωτης

Μέλος του προσωπικού
Απ: Έρευνα γονιδιακής θεραπείας - Recombinant DNA Gene Therapy

πολυ ενδιαφερον
βεβαια ειναι λιγο μεγαλο και δεν εχω τοσο χρονο να το διαβασω τωρα
αλλα οποσδηποτε πρεπει να το κοιταξουμε

σαν πρωτο σχολιο με μια γενικη ματια ακουγεται τελειο
ξεχναμε μεταμοσχευσεις εχουμε 100% αποτελεσμα

ΑΛΛΑ αυτο που λεες σπυρο για το DNA εμενα με βρισκει ΠΟΛΥ επιφυλακτικο
Παρα Πολυ επιφυλακτικο
οτι εχει σχεση με την γενετικη
ωστοσο σαν ενημερωση ειναι πολυ καλα να ξερουμε ολοι μας

αλλα ας μην βιαζομαστε να χαρουμε ολοι μας μιας και δεν εχουν καταφερει να το τελειοποιησουν βρισκεται σε πειραματικο σταδιο
και για να φτασει στο σταδιο το τελικο πιστευω θα περασουν πολλα χρονια
εμας δεν μας πιανει
τα παιδια μας ισως

φαντασου ωσπου να παρει εγριση πρεπει πρωρα να τελειοποιηθει
επειτα να γινουν δοκομες σε πειραματοζωα (ανθρωπους)
και μετα να δουμε ΠΟΣΕΣ ΧΙΛΙΑΔΕΣ ΕΥΡΩ θα κοστιζει

γιατι φαντασου μια σοβαρη μεταμοσχευση εχει 15 χιλιαρικα
βεβεαι αυτο παει αναλογα με το ποσα μαλλια θα βαλεις που θα πας και λοιπα

για ΦΑΝΤΑΣΟΥ αναδημιουργια κελιων θαλακιων κυτταρων και οτι αλλο εχει εκει μεσα

μιλαμε για ΠΟΛΛΑΑΑΑΑΑΑΑ ΛΕΦΤΑΑΑΑΑΑΑΑ
 

Σπύρος

Μέλος του προσωπικού
Απ: Έρευνα γονιδιακής θεραπείας - Recombinant DNA Gene Therapy

δες 'το και αλλιώς :
- με την ίδια τεχνική παρασκευάστηκε η ανθρώπινη ινσουλίνη,ορμόνη αναντικατάστατη για την ζωή των διαβητικών
- αρχικά δεν τους χορηγούσαν σύριγγες(!) και η τιμή της ινσουλίνης ήταν ίση με ένα κατώτερο μισθό(!),αλλά μέσα σε 5-10 χρόνια χορηγείται από όλα τα ταμεία τζάμπα(0% συμμετοχή) και στους απόρους από την Πρόνεια...
δεν λέω- άλλο το ένα,άλλο το άλλο-η έρευνα,η μελέτη και η παρασκευή κοστίζουν σε αυτά,αλλά συνήθως είναι κοινωνικού συμφέροντος η θεραπεία και η κοινωνική κατακραυγή θα είναι παγκόσμια
 

lalakos

Member
Απ: Έρευνα γονιδιακής θεραπείας - Recombinant DNA Gene Therapy

Πιστεύω πως στο κοντινό μέλλον θα φάνουμε τυχεροί, αλλά αυτό που με προβληματίζει είναι οι ημερομηνίες των δημοσιευμάτων. Όλα είναι τη δεκαετία του 90. Έχουμε 08 τώρα. Όμως πραγματικά πιστεύω ότι θα το έχουμε σύντομα.
 

Σπύρος

Μέλος του προσωπικού
Απ: Έρευνα γονιδιακής θεραπείας - Recombinant DNA Gene Therapy

από το '93 και μετά άρχισε η μελέτη,με χρηματοδοτικό μπατζετ ανάλογο του προϋπολογισμού ενός μικρού κράτους... μην τρελαινόμαστε...
 

Παναγιωτης

Μέλος του προσωπικού
Απ: Έρευνα γονιδιακής θεραπείας - Recombinant DNA Gene Therapy

ναι σπυρο αλλο το ενα αλλο το αλλο σωστα
το ειναι θεμα ζωης και το αλλο κοσμιτικης

ενταξει το κρανος σου γραφει την ινσουλινη αλλα δεν νομιζω να σου γραψει φαρμακο για να βγαλεις μαλλια
 
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