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Vitiligo and the melanocyte reservoir.

Falabella R - Indian J Dermatol (2009)

Bottom Line: Repigmentation of vitiligo depends on available melanocytes from three possible sources: from the hair follicle unit which is the main provider of pigment cells, from the border of vitiligo lesions, and from unaffected melanocytes within depigmented areas; pigment cells at these locations originate a perifollicular, border spreading and a diffuse repigmentation pattern.Melanocyte tissue stem cells located in the niche at the bulge region of the hair follicle are the most important sources for providing immature pigment cells that undergo terminal differentiation and originate repigmentation, but cytokines, UVR and other molecules acting in melanogenesis with adequate regulation mechanisms contribute to successful recovery in vitiligo.The presence of keratinocyte stem cells in the interfollicular epidermis raises the question on the possibility of melanocyte stem cells in a similar location and the development of future strategies for therapeutic purposes.

View Article: PubMed Central - PubMed

Affiliation: Universidad del Valle, Carrera 38A # 5A-100, Centro Dermatológico de Cali - CDC, Calle 5B3 # 38-44, Cali, Colombia. rfalabella@uniweb.net.co

ABSTRACT
Repigmentation of vitiligo depends on available melanocytes from three possible sources: from the hair follicle unit which is the main provider of pigment cells, from the border of vitiligo lesions, and from unaffected melanocytes within depigmented areas; pigment cells at these locations originate a perifollicular, border spreading and a diffuse repigmentation pattern. In order for repigmentation to take place under stimulation with diverse therapies, melanocytes should be present in appropriate numbers. Melanocyte tissue stem cells located in the niche at the bulge region of the hair follicle are the most important sources for providing immature pigment cells that undergo terminal differentiation and originate repigmentation, but cytokines, UVR and other molecules acting in melanogenesis with adequate regulation mechanisms contribute to successful recovery in vitiligo. The presence of keratinocyte stem cells in the interfollicular epidermis raises the question on the possibility of melanocyte stem cells in a similar location and the development of future strategies for therapeutic purposes.

No MeSH data available.


Related in: MedlinePlus

The melanocyte reservoir. Illustration depicts the location of keratinocyte and melanocyte stem cells. Other, mature terminal melanocytes are also shown
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Figure 0004: The melanocyte reservoir. Illustration depicts the location of keratinocyte and melanocyte stem cells. Other, mature terminal melanocytes are also shown

Mentions: As mentioned, it is assumed that stem cells are maintained in a specific environment known as the niche. Nishimura et al., in 2002 identified melanocyte stem cells in the lower permanent portion of Dct-lacZ transgenic mice hair follicles, which become activated at early anagen as they are tightly coupled to the hair regeneration cycle.[31] They are located in the lower part of the hair follicle bulge, just below the hair follicle stems cells.[32] The bulge region of the hair follicle, defined as the portion of the outer root sheath of the hair follicle at the insertion site of the arrector pili muscle, constitutes currently the best characterized site of epidermal stem cell populations [Figure 4]. In addition, there is evidence of other stem cells located in the interfollicular epidermis, that is, the portion of the epidermis located between the orifices of hair follicles.[27]


Vitiligo and the melanocyte reservoir.

Falabella R - Indian J Dermatol (2009)

The melanocyte reservoir. Illustration depicts the location of keratinocyte and melanocyte stem cells. Other, mature terminal melanocytes are also shown
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2807704&req=5

Figure 0004: The melanocyte reservoir. Illustration depicts the location of keratinocyte and melanocyte stem cells. Other, mature terminal melanocytes are also shown
Mentions: As mentioned, it is assumed that stem cells are maintained in a specific environment known as the niche. Nishimura et al., in 2002 identified melanocyte stem cells in the lower permanent portion of Dct-lacZ transgenic mice hair follicles, which become activated at early anagen as they are tightly coupled to the hair regeneration cycle.[31] They are located in the lower part of the hair follicle bulge, just below the hair follicle stems cells.[32] The bulge region of the hair follicle, defined as the portion of the outer root sheath of the hair follicle at the insertion site of the arrector pili muscle, constitutes currently the best characterized site of epidermal stem cell populations [Figure 4]. In addition, there is evidence of other stem cells located in the interfollicular epidermis, that is, the portion of the epidermis located between the orifices of hair follicles.[27]

Bottom Line: Repigmentation of vitiligo depends on available melanocytes from three possible sources: from the hair follicle unit which is the main provider of pigment cells, from the border of vitiligo lesions, and from unaffected melanocytes within depigmented areas; pigment cells at these locations originate a perifollicular, border spreading and a diffuse repigmentation pattern.Melanocyte tissue stem cells located in the niche at the bulge region of the hair follicle are the most important sources for providing immature pigment cells that undergo terminal differentiation and originate repigmentation, but cytokines, UVR and other molecules acting in melanogenesis with adequate regulation mechanisms contribute to successful recovery in vitiligo.The presence of keratinocyte stem cells in the interfollicular epidermis raises the question on the possibility of melanocyte stem cells in a similar location and the development of future strategies for therapeutic purposes.

View Article: PubMed Central - PubMed

Affiliation: Universidad del Valle, Carrera 38A # 5A-100, Centro Dermatológico de Cali - CDC, Calle 5B3 # 38-44, Cali, Colombia. rfalabella@uniweb.net.co

ABSTRACT
Repigmentation of vitiligo depends on available melanocytes from three possible sources: from the hair follicle unit which is the main provider of pigment cells, from the border of vitiligo lesions, and from unaffected melanocytes within depigmented areas; pigment cells at these locations originate a perifollicular, border spreading and a diffuse repigmentation pattern. In order for repigmentation to take place under stimulation with diverse therapies, melanocytes should be present in appropriate numbers. Melanocyte tissue stem cells located in the niche at the bulge region of the hair follicle are the most important sources for providing immature pigment cells that undergo terminal differentiation and originate repigmentation, but cytokines, UVR and other molecules acting in melanogenesis with adequate regulation mechanisms contribute to successful recovery in vitiligo. The presence of keratinocyte stem cells in the interfollicular epidermis raises the question on the possibility of melanocyte stem cells in a similar location and the development of future strategies for therapeutic purposes.

No MeSH data available.


Related in: MedlinePlus