不同黑素细胞群在有色毛囊重建中作用的研究

目的观察不同种属小鼠的毛囊细胞能否嵌合重建有色毛囊, 探讨不同黑素细胞群在小鼠有色毛囊重建中的作用。方法选取C57BL/6J、BALB/C胎鼠或乳鼠皮肤, 分离出表皮细胞群、毛囊上皮细胞群和真皮细胞群, 培养、纯化从表皮细胞群获得的表皮黑素细胞。实验包含三部分, ①乳鼠C57BL/6J毛囊重建实验:分为表皮细胞+毛囊上皮细胞组、真皮细胞组;②嵌合毛囊重建实验:分为乳鼠C57BL/6J真皮细胞组、乳鼠BALB/C真皮细胞组、乳鼠BALB/C真皮+乳鼠C57BL/6J真皮细胞组、胎鼠BALB/C真皮细胞+胎鼠C57BL/6J真皮细胞组;③有色毛囊重建实验:分为乳鼠BALB/C真皮细胞+乳鼠C57BL/6J表皮细胞组、乳鼠BALB/C真皮细胞+乳鼠C57BL/6J毛囊上皮细胞组、乳鼠BALB/C真皮细胞+培养的C57BL/6J表皮黑素细胞组。采用小室移植法将不同细胞接种于裸鼠的背部, 每组4只。于移植后4周和8周, 通过大体观察、组织学及免疫荧光评估毛囊重建情况。结果移植后4周和8周, 乳鼠C57BL/6J毛囊重建实验中(本部分实验2组共8只BALB/C裸鼠, 7只存活, 1只因创面感染死亡...     

小鼠皮肤移植细胞有效重建毛发

目的研究将新鲜分离的新生小鼠皮肤细胞移植到免疫缺陷鼠上有效重建毛囊的新技术。方法新生C57小鼠取其皮肤,将表皮和真皮细胞分别分离并混合,做成高浓度的细胞悬液,移植到免疫缺陷鼠NU/NU,CB-17 SCID,NOD SCID上,观察皮肤再生情况。结果细胞移植2周之后,伤口处肉眼可见黑色皮肤形成,3周后长出大量毛发,8周后观察重建的毛发维持良好状态。没有移植细胞的对照观察到伤口愈合但没有毛发形成。组织学分析显示再生的皮肤含有成熟的毛囊和毛干并连有皮脂腺及真皮毛乳头,并且新形成的皮肤不仅有表皮层和真皮层,还有皮下脂肪层,表明移植的细胞可重建完整的皮肤。细胞移植到三种不同的免疫小鼠NU/NU,CB-17 SCID和NOD SCID上,毛囊重建的结果相似。结论创建了一套分离和移植皮肤细胞的技术,可在免疫缺陷鼠上高效地重建毛发。该技术可以用于毛囊再生的研究,并具有潜在的临床应用价值。     

中药黄芪、女贞子、人参促毛发生长的在体研究

目的:以C57BL/6小鼠为动物模型,探讨中药黄芪、女贞子、人参混合煎剂促进C57BL/6小鼠毛发生长的可能机制。方法:中药组小鼠给予中药混合煎剂口饲,对照组给予等量生理盐水,观察小鼠背部皮肤颜色变化和毛发生长情况。同时在光镜下观察小鼠毛囊组织学变化及毛囊内细胞的凋亡的状况。结果:中药组小鼠饲饮中药煎剂后背部皮肤颜色由粉红色变为黑色比对照组提前了1d,背部皮肤颜色由黑色变为灰黑色比对照组延长了1.5d。组织学上,拔毛后第18天对照组小鼠毛囊处于退行中晚期,而中药组仍为生长Ⅵ期和退行早期毛囊。中药组小鼠毛囊内凋亡细胞数量比对照组减少(P<0.001)。结论:黄芪、女贞子、人参混合煎剂促毛发生长作用可能与抑制退行期毛囊内细胞凋亡,诱导和延长C57BL小鼠毛发的生长期有关。     

毛囊混合细胞植入胶原/壳聚糖多孔支架诱导裸鼠毛发生长及支架内形成血管样结构

目的 探讨利用毛囊混合细胞植入胶原,壳聚糖多孔支架内重建毛囊的可行性与支架内血管形成状态.方法 用注射法将体外培养的C57BL/6J近交系乳鼠背部皮肤毛囊混合细胞接种至胶原,壳聚糖多孔支架,培养2周后,将含毛囊混合细胞胶原/壳聚糖多孔支架植入裸鼠皮下,肉眼观察裸鼠背部毛发形成情况.6周后取移植区皮肤组织经10%甲醛固定后行组织学观察(HE染色).结果 移植至裸鼠皮下5周后,裸鼠背部在含毛囊混合细胞的胶原,壳聚糖多孔支架移植区皮肤出现毛发,丰长,6周后取皮肤组织作HE染色发现有分化成熟的毛囊形成,且支架内有血管样结构形成.而空白胶原/壳聚糖多孔支架移植区皮肤未发现毛生长,组织检杳也未发现有毛囊形成,且只有在支架表浅部位有少黑血管样结构形成.结论 毛囊混合细胞植入胶原/壳聚糖多孔支架内可诱导裸鼠毛发的形成,促进支架血管样结构的形成.     

毛囊毛发的病理生理学

<正>0001小鼠皮肤移植细胞有效重建毛发郝泽芳(济南市妇幼保健院妇产科),潘婧,吴训伟//中国皮肤性病学杂志.-2015,29(11).-1130~1133,1144新生C57小鼠取其皮肤,将表皮和真皮细胞分别分离并混合,做成高浓度的细胞悬液,移植到免疫缺陷鼠NU/NU,CB-17SCID,NODSCID上,观察皮肤再生情况。结果:细胞移植2周之后,伤口     

真皮干细胞在毛囊周期中的作用

毛囊由表皮(上皮)及真皮(间充质)组成,它们之间的相互作用在毛囊的形态发生及生长中发挥重要作用,二者之间相互作用是毛囊成功重建的关键因素.在毛发形成过程中,真皮细胞是诱导者,上皮细胞是应答者.真皮鞘和毛乳头内存在毛囊真皮干细胞,属于成体干细胞,具有慢周期、未分化、自我更新和体外增殖能力强的特点.真皮鞘中的真皮干细胞较长寿,可以历经几个毛囊周期,重建真皮鞘.在毛囊周期的生长期,真皮鞘中的干细胞产生新细胞提供给毛乳头;在退行期,真皮干细胞子代移出毛乳头或死亡.毛囊真皮细胞对于损伤和疾病之后的毛囊重建及修复具有重要意义.     

血管内皮生长因子165基因转染小鼠硬皮病皮损的实验研究

目的:探讨硬皮病基因治疗的新方法。方法:建立小鼠硬皮病动物模型后,应用电穿孔技术将血管内皮生长因子(VEGF)165真核表达质粒导入硬皮病小鼠硬化的皮下;再利用免疫组化、原位杂交法检测小鼠硬皮病皮损VEGF165的表达及观察组织病理改变。结果:①转基因后硬皮病鼠毛发生长明显增多,而未转基因硬皮病鼠毛发未见生长。②组织病理检查示转基因鼠毛囊明显增生,毛囊数每一低倍视野平均为(12.0±1.6)个,显著高于未转基因硬皮病鼠组(P<0.05)。真皮厚度增加,新生血管增加。③免疫组化、原位杂交法检测示转基因鼠表皮和真皮细胞及间质VEGF165表达明显增加。结论:电穿孔技术可将外源性基因转入小鼠硬化的皮肤,使其高表达。外源性VEGF165基因转染后,可明显促进小鼠硬化的皮肤毛发生长,已萎缩的真皮组织增生。     

裸鼠重建毛囊的组织学研究

目的 观察毛乳头细胞诱导毛囊再生民政部和毛囊重建情况。方法 采用器官型培养技术和裸鼠移植技术,将培养的毛囊毛乳头细胞、真皮鞘细胞和头皮（或包皮）真皮成纤维细胞分别制成胶原凝胶,再接种于毛囊上皮上段、下段和球部细胞,进行体外增习移植试验,结果 在毛囊毛乳头细胞与毛囊各段上皮细胞的器官型培养中均可见毛囊样结构形成;毛囊真皮鞘细胞凝胶上培养的毛球部细胞也重建出毛囊样结构。移植到裸鼠皮下后则可见较为完整的     

毛乳头细胞与毛发上皮细胞相互作用的研究

目的探讨人毛乳头细胞和毛发上皮细胞间的相互作用,了解毛发生长周期的调控,寻找体内外毛囊重建的途径。方法人毛乳头细胞和毛发上皮细胞分室和共同培养于 DMEM培养基中,在不同时相计数两种细胞,并观察细胞的生长方式。结果毛乳头细胞和毛发上皮细胞的生长能相互促进,毛发上皮细胞能诱导培养的毛乳头细胞形成毛乳头样结构。结论毛囊真－表皮间的作用是双向的,它们共同控制着毛囊的生长和发育。     

毛囊干细胞与组织工程研究进展

毛囊干细胞研究取得突破性进展的标志是由孙同天、Lavker和Cotsarelis等提出了隆突激活假说,明确了其定位的部位,是少数几种成体干细胞首先被明确定位的干细胞之一,并逐步得到了验证。毛囊干细胞不仅可以分化为毛囊上皮细胞,而且可以分化为皮脂腺细胞、表皮角质形成细胞,其分化过程是干细胞分化为短暂倍增细胞,最后分化为终末分化细胞。近年来进一步证明了毛囊隆突部也是多种干细胞的居住地,包括黑素干细胞,和毛囊干细胞存在同步化激活的机制。Wnt/β-catenin是毛囊发育、再生循环的基本信号通路,使毛囊在再生过程出现着色一致的毛发。诱导和重建毛囊形成是组织工程皮肤最主要的目标之一,毛乳头细胞的凝集性生长特性是诱导毛囊形成的条件,因此,维持毛乳头细胞凝集性生长特性主要有细胞团块法、低黏附性培养板(或高分子材料膜)法、悬滴培养法和胶原凝胶成球法,以实现体外重建毛乳头的目的。毛囊组织工程在体外还不能真正诱导形成,现有的毛囊再生或新生的成功方法还是须移植到动物体内,才能形成完整毛囊并产生毛发。主要方法有移植小室法、混合游离细胞注射法和皮瓣法。诱导毛囊形成比较成功的细胞是啮齿类动物来源的胚胎或新生鼠毛囊细胞和人胚胎毛囊细胞,成年人头皮毛囊来源细胞目前仍未能诱导出毛囊新生或再生。     

Skin equivalent assay: An optimized method for testing for hair growth reconstitution capacity of epidermal and dermal cells

Hair follicle reconstitution requires highly organized epithelial‐mesenchymal interactions. Skin equivalents containing the epidermal and dermal cells with hair reconstitution capacity can reproduce these processes, but have not been established. This study was conducted to develop a hair follicle‐producing three‐dimensional (3D) skin equivalent assay using neonate mouse epidermal and dermal cells. A skin equivalent comprised of mouse dermal cells (MDCs) embedded in type I collagen and overlaid with mouse epidermal cells (MECs) was used. MDCs were mixed with type I collagen and cultured for 7 days. One day after adding MECs on top, the composites were grafted onto nude mice. MDCs cultured on a two‐dimensional (2D) plate for 7 days and mixed with MECs as a negative control, and freshly isolated MDCs and MECs mixture (chamber assay) as a positive control were also grafted. Six weeks after grafting, regenerated hair follicles were analysed. Our 3D skin equivalent culture assay reproducibly regenerated hair follicles, while MDCs precultured in the 2D model with MECs did not. Compared to the chamber assay, which produced randomly oriented hair follicles, nearly all regenerated hair follicles in our assay extruded through the skin and numerous regenerated hair follicles were higher than those in the chamber assay. Several representative genes associated with hair induction showed higher expression in our assay than in the 2D model. When Wnt3a was added, the number of regenerated hairs increased. Organized hair follicle regeneration was accomplished using our assay. This approach can be applied to assess a test agent with hair growth‐promoting effects.     

Comparisons of mouse models for hair follicle reconstitution

Three methods are currently available to reconstitute hair follicles in mice. Direct comparisons have yet to be made to determine which method is most efficient. In this study, mouse epithelial cells (MECs) and mouse dermal cells (MDCs) were grafted onto the dorsal skin of nude mice using the chamber, flap or patch assays. Comparisons were made based on gross, scanning electron microscopic and histological observations. MDCs alone induced hair follicle reconstitution with the production of hairs yielding false-positive results caused by contamination by hair follicle remnants. Neither primary MECs nor cultured MDCs alone formed hair follicles but did result in hair follicle formation when mixed together. Frozen MECs or MDCs resulted in decreased hair follicle-inductive activity but could still regenerate hairs. The hair patch assay was the quickest model (20±3 days) to determine whether cell mixtures would reconstitute hair follicles that produce hairs; however, the hair follicles were randomly orientated and often associated with foreign body granulomas. The flap assay took the longest time (29±2 days) to produce follicles and hairs to develop with a clinically natural appearance, but an epidermal sheet was needed. The chamber assay was the most labour-intensive and cell number-dependent procedure but follicles developed in a dense, clinically normal manner.     

Sheep vibrissa dermal papillae induce hair follicle formation in heterotypic skin equivalents

Cultured skin equivalents were constructed by combining keratinocytes, outer root sheath cells or isolated epidermis, in vitro, with a matrix composed of collagen and cultured fibroblasts. When equivalents were grafted on to host animals, the epidermis thickened considerably, and tongues of cells penetrated the dermis, giving the dermal/epidermal junction a deeply sculptured profile. No cutaneous appendages were found in these grafts. We explored the possibility of inducing hair follicles by incorporating ovine hair follicle dermal papillae into constructs composed of an isolated epidermal sheet and a contracted dermal equivalent. In vitro, no morphogenetic changes associated with follicle formation were observed in the recombinants, but when grafted on to nude mice, follicle-like structures were identified. The follicles were large, and had developed adjacent to the epidermis, indicating that the matrix environment of the induced follicles may not have been compatible with the downgrowth of the epidermal plugs normally observed during follicle formation in living skin. Nevertheless, in histological sections, the induced structures displayed many of the morphological characteristics of follicles in vivo, including the production of keratinized hairs. These results indicate that skin equivalents provide a useful model for the study of the chemical and structural features of matrices that facilitate hair follicle development.     

Hair follicle reformation induced by dermal papilla cells from human scalp skin

To investigate the possibility of hair follicle reformation induced by dermal papilla cells in vivo and in vitro. Dermal papilla cells, dermal sheath cells obtained from human scalp skin by enzyme digestion were mixed with collagen to form mesenchymal cell-populated collagen gels. Superior and inferior epithelial cells and bulb matrical cells were then cultured on these gels by organotypic culture to recombine bilayer artificial skins. Dermal papilla cells and outer root sheath keratinocytes were mingled together and transplanted under subcutaneous tissue of the dorsal skin of nude mice. The results of histologic examination was observed with HE stain. These recombinants by organotypic culture all reformed bilayer structure like nature skin. Hair follicle-like structure reformation was found in dermal sheath cell-populated collagen gel when combined with superior or inferior epithelial cells. Dermal papilla cells also induced superior and inferior epithelial cells to form hair follicle on nude mice. Low passage dermal papilla cells mixed with hair follicle epithelial cells reformed many typical hair follicle structures and produced hair fibres after transplantation on nude mice. The dermal part of hair follicle, such as dermal papilla cells and dermal sheath cells, has the ability to induce hair follicle formation by interaction with the epithelial cells of hair follicle.     

A model system to analyse the ability of human keratinocytes to form hair follicles

Earlier studies showed that dermal cells lose trichogenic capacity with passage, but studies on the effect of keratinocyte passage on human hair follicle neogenesis and graft quality have been hampered by the lack of a suitable model system. We recently documented human hair follicle neogenesis in grafted dermal‐epidermal composites, and in the present study, we determined the effects of keratinocyte passage on hair follicle neogenesis. Dermal equivalents were made with cultured human dermal papilla cells and were overlaid with either primary or passaged human keratinocytes to form dermal‐epidermal composites; these were then grafted onto immunodeficient mice. Superior hair follicle neogenesis was observed using early keratinocyte cultures. Characteristics such as formation of hair shafts and sebaceous glands, presence of hair follicles with features of anagen or telogen follicles, and reproducible hair and skin function parameters make this model a tool to study human hair follicle neogenesis and development.     

Plasticity of hair follicle dermal cells in wound healing and induction

The capacity of adult hair follicle dermal cells to participate in new follicle induction and regeneration, and to elicit responses from diverse epithelial partners, demonstrates a level of developmental promiscuity and influence far exceeding that of interfollicular fibroblasts. We have recently suggested that adult follicle dermal cells have extensive stem or progenitor cell activities, including an important role in skin dermal wound healing. Given that up to now tissue engineered skin equivalents have several deficiencies, including the absence of hair follicles, we investigated the capacity of follicle dermal cells to be incorporated into skin wounds; to form hair follicles in wound environments; and to create a hair follicle-derived skin equivalent. In our study, we implanted rat follicle dermal cells labelled with a vital dye into ear and body skin wounds. We found that they were incorporated into the new dermis in a manner similar to skin fibroblasts, but that lower follicle dermal sheath also assimilated into hair follicles. Using different combinations of follicle dermal cells and outer root sheath epithelial cells in punch biopsy wounds, we showed that new hair follicles were formed only with the inclusion of intact dermal papillae. Finally by combining follicle dermal sheath and outer root sheath cells in organotypic chambers, we created a skin equivalent with characteristic dermal and epidermal architecture and a normal basement membrane - the first skin to be produced entirely from hair follicle cells. These data support the hypothesis that follicle dermal cells may be important in wound healing and demonstrate their potential usefulness in human skin equivalents and skin substitutes. While we have made progress towards producing skin equivalents that contain follicles, we suggest that the failure of cultured dermal papilla cells to induce follicle formation in wounds illustrates the complex role the follicle dermis may play in skin. We believe that it demonstrates a genuine dichotomy of activity for follicle cells within skin.     

培养毛乳头细胞生物学特性和毛囊重建的研究

目的 观察毛乳头细胞在体内外诱导毛囊再生和支持毛囊生长情况。方法 采用免疫组化、原位杂交、毛囊器官型培养和裸鼠移植技术，观察不同传代培养的毛乳头细胞碱性成纤维细胞生长因子，内皮素和干细胞因子的表达变化情况。结果 低传代培养的毛乳头细胞的内皮素和干细胞因子表达较强，传代6代后减弱。用低传代培养的毛乳头细胞与毛囊上皮细胞在毛囊器官型培养模型中可见毛囊样结构形成，移植到裸鼠后可见较为完整的毛囊形成。用低传代培养的毛乳头细胞与毛囊上皮细胞按一定比例混合后直接注射到裸鼠皮下，也可见毛囊样结构形成。发现毛乳头细胞诱导毛囊再生的能力与其表达内皮素和干细胞因子的强弱相关。结论 低传代培养的毛乳头细胞在体内外均具有诱导毛囊再生的能力，并且与其表达内皮素和干细胞因子的强弱相关。     

Human follicular stem cells: their presence in plucked hair and follicular cell culture

BACKGROUND AND OBJECTIVES: A considerable portion of the hair follicle remains attached to plucked hair and can be used for follicle cell culture. In this study we have phenotyped these cells in an attempt to identify the stem cell fraction. Reports in the literature have indicated that this cell population may be positive for cytokeratin (CK) 19. Because stem cells in general need to be protected from apoptosis, the presence of the apoptosis-suppressing Bcl-2 protein, together with the absence of the apoptosis-promoting Bax and the CK profile may be used as an indicator of the stem cell population in the hair follicle, and in cultures of hair follicle cells. METHODS: Hair follicles from skin biopsies and plucked hair were derived from the scalps of healthy volunteers. Follicular cells were cultured from the plucked hairs. These hair follicles, plucked hairs and cultured cells were examined for their CK profiles, which are indicative of the type of cell (basal/stem cells) and for their status with respect to the proliferation marker Ki-67, Bax and Bcl-2. RESULTS: We found coexpression for CK19 and Bcl-2, but not Bax in two distinct areas, localized in the upper and lower third of the follicle from both skin biopsies and plucked hairs, while proliferation markers were negative in these areas. CK19 and Bcl-2 were also coexpressed in combination in a fraction of the follicular cell culture. The skin basal cell marker CK14 could be found throughout the outer root sheath of the hair follicle from both skin biopsies and plucked hairs, as well as in the follicular cell culture. CONCLUSIONS: Thus, CK19/Bcl-2-positive and Bax-negative cells can be obtained from cells derived from plucked hair and are retained in cultures made from these cells. If this phenotype represents follicular stem cells, our finding endorses the assumption that stem cells are located in the bulge area of the hair follicle, as we did not find them in or near the dermal papilla.     

Isolation of murine hair-inducing cells using the cell surface marker prominin-1/CD133

Hair is a mini-organ in which dermal papilla (DP) cells play important roles in hair follicle morphogenesis and formation via interactions with epithelial cells. DP cells have previously been difficult to analyze because of the lack of a specific surface marker. We have demonstrated that prominin-1/CD133 (CD133) is a useful marker for murine DP cells. DP cells express CD133 during the early anagen stage (active growth phase) not only during hair morphogenesis, but also during the growth phase of hairs after birth. Gene expression and flow cytometric analysis revealed that CD133-positive (+) cells in the skin possess the characteristics of DP cells. The CD133(+) cells isolated from embryonic or adult skin-induced new hair follicles in vivo when they were transplanted into nude mice mixed with embryonic epithelial cells, but CD133-negative (-) cells could not. We propose that the CD133 is a novel surface marker useful for collecting DP cells in the anagen stage and for analyzing the function of DP.