Induced pluripotent stem cells and neurological disease models / 生理学报

The availability of human stem cells heralds a new era for in vitro cell-based modeling of neurodevelopmental and neurodegenerative diseases. Adding to the excitement is the discovery that somatic cells of patients can be reprogrammed to a pluripotent state from which neural lineage cells that carry the disease genotype can be derived. These in vitro cell-based models of neurological diseases hold promise for monitoring of disease initiation and progression, and for testing of new drug treatments on the patient-derived cells. In this review, we focus on the prospective applications of different stem cell types for disease modeling and drug screening. We also highlight how the availability of patient-specific induced pluripotent stem cells (iPS cells) offers a unique opportunity for studying and modeling human neurodevelopmental and neurodegenerative diseases in vitro and for testing small molecules or other potential therapies for these disorders. Finally, the limitations of this technology from the standpoint of reprogramming efficiency and therapeutic safety are discussed.

Transplantation of human bone marrow-derived mesenchymal stem cells transfected with ectodysplasin for regeneration of sweat glands / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Patients with severe full-thickness burn injury suffer from their inability to maintain body temperature through perspiration because the complete destructed sweat glands can not be regenerated. Bone marrow-derived mesenchymal stem cells (BM-MSCs) represent an ideal stem-cell source for cell therapy because of their easy purification and multipotency. In this study, we attempted to induce human BM-MSCs to differentiate into sweat gland cells for sweat gland regeneration through ectodysplasin (EDA) gene transfection.</p><p><b>METHODS</b>The dynamic expression of EDA and EDA receptor (EDAR) were firstly observed in the sweat gland formation during embryological development. After transfection with EDA expression vector, human BM-MSCs were transplanted into the injured areas of burn animal models. The regeneration of sweat glands was identified by perspiration test and immunohistochemical analysis.</p><p><b>RESULTS</b>Endogenous expression of EDA and EDAR correlated with sweat gland development in human fetal skin. After EDA transfection, BM-MSC acquired a sweat-gland-cell phenotype, evidenced by their expression of sweat gland markers by flow cytometry analysis. Immunohistochemical staining revealed a markedly contribution of EDA-transfected BM-MSCs to the regeneration of sweat glands in the scalded paws. Positive rate for perspiration test for the paws treated with EDA-transfected BM-MSCs was significantly higher than those treated with BM-MSCs or EDA expression vector (P < 0.05).</p><p><b>CONCLUSIONS</b>Our results confirmed the important role of EDA in the development of sweat gland. BM-MSCs transfected with EDA significantly improved the sweat-gland regeneration. This study suggests the potential application of EDA-modified MSCs for the repair and regeneration of injured skin and its appendages.</p>

A new way for isolation and cultivation of sweat gland ductal cells from human split-thickness skin in vitro / 中华外科杂志

<p><b>OBJECTIVE</b>To explore a new method of isolation and culture of eccrine sweat gland ductal cells from human split-thickness skin graft in vitro.</p><p><b>METHODS</b>Human split-thickness skin graft which was presented by volunteer (n = 10) was digested with type II collagenase, and then sweat gland duct were isolated from the split-thickness skin graft, primary cultures were incubated at 37 degrees C in humidified atmosphere of 5% CO2, 95% O2. The cultured eccrine sweat gland ductal cells were identified by analysis CEA, CK8, CK18, CK19 antigens expression with flow cytometry, RT-PCR and Western Blot, and by detecting the electrophysiology with whole cell patch clamp technology.</p><p><b>RESULTS</b>The isolated eccrine sweat gland ductal cells could grow by adhering to the wall, proliferate in vitro after 48 h of adhering to the wall, and confluens after 2 - 4 weeks of adhering to the wall. The FACs analysis showed the expression of CEA was (90.26 +/- 1.12)%, (89.70 +/- 1.43)%, and CK8 was (94.41 +/- 1.84)%, (93.65 +/- 1.63)% in primary cultured sweat gland ductal cells and primary cultured eccrine sweat gland cells, respectively, and there is no significant difference between the two groups (P > 0.05). Immunocytochemistry staining showed CEA, CK8, CK18, CK19 was positive in sweat gland duct cells, RT-PCR revealed that CEA, CK8, CK18 and CK19 gene expression in sweat gland ductal cells, and Western Blot analysis showed the expression of CEA brand, CK8 brand, CK18 brand, and CK19 brand in sweat gland ductal cells, patch clamp indicated that this cells has distinct amiloride sensitive Na(+) channels.</p><p><b>CONCLUSIONS</b>The cultured human eccrine sweat gland duct cells in vitro display the markers and biological characteristics of sweat gland epithelial lineage, and this method of digest the split-thickness skin graft to get the sweat gland duct cells is better than classical dissect sweat gland under dissect microscope.</p>

Promotive effect of adipose-derived stem cells on the wound model of human epidermal keratinocytes in vitro / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the migrating effect of adipose derived stem cells (ADSCs) on the wound model of human epidermal keratinocyte (HEKa).</p><p><b>METHODS</b>Rat ADSCs (rADSCs) were isolated and cultured (n = 10), rADSCs were direct co-cultured with HEKa cells in experiment group (experimental group, n = 10). In the control groups, rADSCs were indirect co-cultured with HEKa cells in transwell chamber (indirect group, n = 8), or HEKa was cultured alone (single group, n = 8). Then confluent HEKa cells were scraped to establish a wound model under invert microscope. After scraped 24, 48, and 72 h, cell numbers of which migrated across the edge of the wound was measured, the rate of wound healing was calculated by using SigmaScan Pro 5 software, and the proliferating effect of rADSCs on HEKa were examined by incorporation of [(3)H] thymidine.</p><p><b>RESULTS</b>The cells migrated across the edge of wound after 24 hours in experimental group, indirect group, and single group were (9.2 + or - 0.2), (5.0 + or - 0.3), (4.2 + or - 0.3), and were (58.5 + or - 0.4), (26.5 + or - 0.3), (20.7 + or - 0.5) 48 hours after, and were (125.8 + or - 0.4), (43.0 + or - 0.5), (35.6 + or - 0.5) cells/HP 72 hours after, respectively; the numbers were all significantly higher in experimental group than those in control groups (P < 0.05). The rates of wound healing after scraped 72 hours were 61.0% + or - 3.0%, 35.0% + or - 2.5% and 32.0 + or - 2.1%, the outcome in experimental group was significantly better than in the control groups (P < 0.05). And the thymidine feeding displayed the proliferation of HEKa in the three groups were (1440 + or - 210), (1050 + or - 280) and (1130 + or - 390) cpm/10(5) cell, and there was significant difference between the experimental and the control groups (P < 0.05).</p><p><b>CONCLUSIONS</b>The rADSCs can promote the migration of HEKa by direct contact with it.</p>

Protective effect of non-mitogenic haFGF on cerebral ischemia-reperfusion injury in mice / 中国药理学通报

Aim To investigate the protective effect of non-mitogenic human acidic fibroblast growth factor (nm-haFGF) on cerebral ischemia-reperfusion injury in mice. Methods Cerebral ischemia-reperfusion model was made by ligating bilateral carotid for 20 minutes in mice. These mice were randomly divided into model group( iv NS), two doses of nm-haFGF (iv 25、50 ?g?kg-1) groups, rhaFGF group(iv 50 ?g?kg-1) and sham- operated group. Step down test and Y-type electric maze were used to examine the effect of nm-haFGF on learning and memory of mice, then Even′s Blue(EB) level and NO level in brain of these mice were measured. Results The nm-haFGF significantly decreased numbers of errors of mice in 5 min in step down test and in Y-type electric maze test; EB and NO levels in brain of these mice were lower than those of model group respectively. Conclusion The nm-haFGF can protect cerebral ischemia-reperfusion injury in mice.

Functional sweat gland implantation:a report of two cases / 解放军医学杂志

Background The loss of perspiration after a massive deep burn hampers the survivor to lead a life of high quality, as they are deprived the function of regulating body temperature through perspiration during sultry months. With maturation of science of burn care, the number of survivors is increased, therefore, it is imperative that this problem should be tackled in order to improve their quality of life. Objective To explore the possibility of transdifferentiating bone marrow mesenchymal stem cells (MSCs) into sweat gland cells (SGCs), and implanting the latter into fresh skin wound to generate functional sweat glands. Methods Human bone marrow MSCs and SGCs were isolated from the same patients. They were identified with specific markers, and then co-cultured. The stem cells which subsequently exhibited the phenotype of sweat gland cells were implanted into scald injured paws of nude mice, and regeneration of functioning sweat glands was confirmed by perspiration test (iodine and starch) and histological examination. A male patient bearing almost iden- tical burn scars on the posterior aspect of both arms was enrolled for clinical trial. The scars were first proved to be anhydrotic with iodine and starch test. With patient's written consent, the clinical trial was carried out. Bone marrow MSCs and sweat gland cells were obtained from the patient. After being heat shocked, the SGCs were co-cultured with MSCs. Three days later, the scars of both arms were excised. MSCs having acquired the phenotype of sweat gland cells after co-culture were evenly spread onto the excision wound on the right arm. They were covered with a piece of acellular allogeneic dermis, which was perforated with numerous micropores. On top of the latter, micrografts of autologous origin were transplanted, and the wound was finally covered with a piece of allogeneic skin graft. The wound on the left side was similarly covered, but without transdifferentiated MSCs. After complete healing of the wounds, perspiration test with iodine and starch was performed, and biopsy was taken from the MSCs transplanted area. The components of the sweat collected from the implantation area were analyzed and compared with that from normal skin elsewhere on the body. The same procedure was performed in a girl patient with a chin-neck contracture. The scar was totally excised, and into one third of the excision wound in vitro transdifferentiated MSCs were implanted similar to the above patient. The examinations were repeated after wound healed. Results In the animal experiment, it was shown that there was regeneration of functional sweat glands in the burned paws of the nude mice. In human patients, all wounds healed nicely. The areas where transdifferented MSCs were implanted showed positive iodine-starch perspiration test. Histological and immunohistochemical examination confirmed that the transformed MSCs bore the specific marker carcinoembryonic antigen (CEA) of sweat gland cells. Biochemical analysis of the excreted sweat contained similar components as that of sweat collected from normal skin. Conclusions MSCs can be transdifferentiated into SGCs in vitro, and they can be implanted into a fresh wound to form functional sweat glands. However, enormous amount of work should be done before the same result would be realized in patients with massive deep burn within a short duration after the injury, so that the patients could regain the function of perspiration after surviving the massive loss of normal skin.