The damage of sweat glands in patients with extensive deep burns results in the loss of thermoregulation, which seriously affects the quality of life of patients. At present, there are many researches on the repair of sweat gland function, but the mechanism of human sweat gland development has not been fully clarified. More and more studies have shown that the cascaded pathways of Wnt/β-catenin, ecto- dysplasin A/ectodysplasin A receptor/nuclear factor-κB, sonic hedgehog, and forkhead box transcription factor jointly affect the development of sweat glands, and it has been reported that the cascaded signaling pathways can be used to achieve the reconstruction of sweat adenoid cells in vitro. This article reviews the signaling pathways that affect the development of sweat glands and their involvement in the reconstruction of sweat adenoid cells in vitro.
Adenoids/metabolism* ; Hedgehog Proteins/metabolism* ; Humans ; Quality of Life ; Signal Transduction ; Sweat/metabolism* ; Sweat Glands/physiology*

Sweat gland is one of the important appendage organs of the skin, which plays an important role in thermoregulation and homeostasis maintenance. Sweat glands are damaged and unable to self-repair after burns, resulting in perspiration disorders eventually. However, current clinical strategies cannot restore the function of the damaged sweat glands effectively. Therefore, it is urgent to seek treatments that can promote the regeneration of sweat glands and restore their normal functions. Stem cells have extensive sources, low immunogenicity, high proliferation capacity, and multi-directional differentiation potential, which have become a focus in the field of regenerative medicine. In recent years, a variety of stem cells have been induced to differentiate into sweat gland-like tissue with certain secretory function, which provides treatment direction for sweat gland regeneration after burns in clinic. This article reviews the recent research advances on the application of stem cells in sweat gland regeneration from the perspectives of the manner by which stem cells transform into sweat gland cells in different environments and their influencing factors.
Cell Differentiation/physiology* ; Regeneration/physiology* ; Skin ; Stem Cells ; Sweat Glands/physiology*

BACKGROUNDSweat glands (SGs) can not regenerate after complete destruction in the severe skin injury, so it is important to find a ideal stem cell source in order to regenerate functional SGs. Hair follicle stem cells (HFSCs) possess the obvious properties of the adult stem cells, which are multipotent and easily accessible. In this research, we attempted to direct the HFSCs suffered from the sweat gland cells (SGCs) special differentiation by a co-operative coculture system in vitro.

METHODSThe designed co-culture microenvironment in the transwell was consist of two critial factors: heat shocked SGCs and dermis-like mesenchymal tissue, which appeared independently in the two control groups; after induction, the purified induced SGC-like cells were transplanted into the full-thickness scalded wounds of the nude mice, after 4 weeks, the reconstructed SG-like structures were identified by immunohistochemical and immunofluorescence analysis.

RESULTSA part of HFSCs in experimental group finally expressed SGCs phenotypes, by contrast, the control group 1 which just containing dermis-like mesenchymal tissue failed and the control group 2 consisted of heat shocked SGCs was in a poor efficiency; by immunofluorescence staining and flow cytometry analysis, the expression of HFSCs special biomarkers was down regulated, instead of the positive efficiency of SGCs special antigens increased; besides, the induced SGCs displayed a high expression of ectodysplasin A (EDA) and ectodysplasin A receptor (EDAR) genes and proteins; after cell transplantation, the youngest SG-like structures formed and be positive in SGCs special antigens, which never happened in untreated wounds (P < 0.05).

CONCLUSIONThe HFSCs are multipotential and capable in differentiating into SGCs which promise a potential stem cells reservoir for future use; our special co-culture microenvironment is promising for HFSCs differentiating; the induced SGCs are functional and could work well in the regeneration of SGs.

Animals ; Blotting, Western ; Cell Differentiation ; physiology ; Cell Proliferation ; Fluorescent Antibody Technique ; Hair Follicle ; cytology ; Humans ; Immunohistochemistry ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Sweat Glands ; cytology

No abstract available.
Adenosine Triphosphate/pharmacology ; Anions/metabolism ; Bicarbonates/metabolism* ; Chlorides/metabolism* ; Cyclic AMP/pharmacology ; Cystic Fibrosis Transmembrane Conductance Regulator/physiology* ; Electric Conductivity ; Electrophysiology ; Gluconates/pharmacology ; Human ; Membrane Potentials/physiology ; Membrane Potentials/drug effects ; Potassium/pharmacology ; Sweat Glands/metabolism*

BACKGROUNDIn hypertrophic scar tissue, no sweet gland and hair follicle exist usually because of the dermal and epidermal damage in extensive thermal skin injury, thus imparing regulation of body temperature. This study was designed to reveal the morphological and distributional characteristics of the sweat glands in normal skin and hypertrophic scar obtained from children and adults, and to study the possible interfering effects of the scar on regeneration of the sweat gland after burn injury.

METHODSBiopsies of hypertrophic scar were taken from four children (4 - 10 years) and four adults (35 - 51 years). Normal, uninjured full-thickness skin adjacent to the scar of each patient was used as control. Keratin 19 (K19) was used as the marker for epidermal stem cells and secretory portion of the sweat glands, and keratin 14 (K14) for the tube portion, respectively. Immunohistochemical and histological evaluations were performed.

RESULTSHistological and immunohistochemical staining of skin tissue sections from both the children and adults showed K19 positive cells in the basement membrane of epidermis of normal skin. These cells were seen only single layer and arranged regularly. The secretory or duct portion of the eccrine sweat glands was situated in the dermis and epidermal layer. However, in the scar tissue, K19 positive cells were scant in the basal layer, and the anatomic location of the secretory portion of sweat glands changed. They were located between the border of the scar and reticular layer of the dermis. These secretory portions of sweat glands were expanded and were organized irregularly. But a few K14 positive cells were scattered in the scar tissues in cyclic form.

CONCLUSIONSThere are some residual sweat glands in scar tissues, in which the regeneration process of active sweat glands is present. Possibly the sweat glands could regenerate from adult epidermal stem cells or residual sweat glands in the wound bed after burn injury.

Adult ; Burns ; pathology ; Child ; Child, Preschool ; Cicatrix, Hypertrophic ; metabolism ; pathology ; Epidermis ; cytology ; Humans ; Immunohistochemistry ; Keratin-14 ; Keratins ; analysis ; Middle Aged ; Regeneration ; Skin ; cytology ; Stem Cells ; cytology ; Sweat Glands ; pathology ; physiology