Muse Cells Derived from Dermal Tissues Can Differentiate into Melanocytes.

The objective of the authors has been to obtain multilineage-differentiating stress-enduring cells (Muse cells) from primary cultures of dermal fibroblasts, identify their pluripotency, and detect their ability to differentiate into melanocytes. The distribution of SSEA-3-positive cells in human scalp skin was assessed by immunohistochemistry, and the distribution of Oct4, Sox2, Nanog, and SSEA-3-positive cells was determined by immunofluorescence staining. The expression levels of Sox2, Oct4, hKlf4, and Nanog mRNAs and proteins in Muse cells were determined by reverse transcription polymerase chain reaction (RT-PCR) analyses and Western blots, respectively. These Muse cells differentiated into melanocytes in differentiation medium. The SSEA-3-positive cells were scattered in the basement membrane zone and the dermis, with comparatively more in the sebaceous glands, vascular and sweat glands, as well as the outer root sheath of hair follicles, the dermal papillae, and the hair bulbs. Muse cells, which have the ability to self-renew, were obtained from scalp dermal fibroblasts by flow cytometry sorting with an anti-SSEA-3 antibody. The results of RT-PCR, Western blot, and immunofluorescence staining showed that the expression levels of Oct4, Nanog, Sox2, and Klf4 mRNAs and proteins in Muse cells were significantly different from their parental dermal fibroblasts. Muse cells differentiated into melanocytes when cultured in melanocyte differentiation medium, and the Muse cell-derived melanocytes expressed the melanocyte-specific marker HMB45. Muse cells could be obtained by flow cytometry from primary cultures of scalp dermal fibroblasts, which possessed the ability of pluripotency and self-renewal, and could differentiate into melanocytes in vitro.

Muse Cells, a New Type of Pluripotent Stem Cell Derived from Human Fibroblasts.

A new type of mesenchymal stem cells (MSCs) that expresses stage-specific embryonic antigen 3 (SSEA-3) and the mesenchymal cell marker CD105 are known as multilineage-differentiating stress-enduring (Muse) cells. Studies have shown that stem cells in suspension cultures are more likely to generate embryoid body-like stem cell spheres and maintain an undifferentiated phenotype and pluripotency. We separated Muse cells derived from human dermal fibroblasts by long-term trypsin incubation (LTT) through suspension cultures in methylcellulose. The Muse cells obtained expressed several pluripotency markers, including Nanog, Oct4, Sox2, and SSEA-3, and could differentiate in vitro into cells of the three germ layers, such as hepatocytes (endodermal), neural cells (ectodermal) and adipocytes, and osteocytes (mesodermal cells). These cells showed a low level of DNA methylation and a high nucleo-cytoplasmic ratio. Our study provides an innovative and exciting platform for exploring the potential cell-based therapy of various human diseases using Muse cells as well as their great possibility for regenerative medicine.

N,N,N,N-Tetra-ethyl-6-{2-[(E)-1-(4-nitro-phen-yl)ethyl-idene]hydrazino}-1,3,5-triazine-2,4-diamine.

The title compound, C(19)H(28)N(8)O(2), was prepared by the reaction of N(2),N(2),N(4),N(4)-tetra-ethyl-6-hydrazino-1,3,5-triazine-2,4-diamine and 1-(4-nitro-phen-yl)ethanone in ethanol at room temperature. The mol-ecular conformation is stabilized by intra-molecular C-H⋯N hydrogen-bonding inter-actions. There are also inter-molecular N-H⋯O hydrogen bonds, and C-H⋯π and π-π inter-actions, which help to stabilize the crystal structure. The centroid-centroid distance is 3.6172 (10) Šbetween adjacent benzene and 1,3,5-triazine rings.