ABSTRACT
BACKGROUND:Epidermal stem cells as special stem cells of the skin not only plays an important role in maintaining the metabolism of skin, but also is closely related to wound repair, which are the basis for the occurrence and repair of skin and its appendages. Now, epidermal stem cells have been paid great attention on the research of gene therapy and celltherapy with its specific biological advantages. OBJECTIVE:To summarize the research status on features and clinical application of epidermal stem cells. METHODS:A computer-based online retrieval of CNKI, PubMed database and Google scholar was performed for searching papers about clinical application of epidermal stem cells using the keywords of“epidermal stem cells, stem cells division, stem cells culture, clinical application”in Chinese and English. Older theoretical perspectives and repetitive research were excluded. Finally, only 41 articles were included in result analysis. RESULTS AND CONCLUSION:Epidermal stem cells have the great potential of proliferation and multi-directional differentiation, and have important significances for large-area skin defects (burn and trauma), skin tissue engineering, and gene therapy. There are stil many problems that need to be solved, such as how to screen surface markers special for epidermal stem cells and how to induce skin differentiation of epidermal stem cells.
ABSTRACT
Objective To study the relationship of proliferation and activation of T lymphocyte subsets and disease progression in antiretroviral-naive human immunodeficiency virus(HIV)-1-infected individuals.Methods Forty-nine antiretroviral-naive,chronically HIV-1 infected patients and 16 healthy,HIV-1 negative controls were enrolled in this study.The patients were divided into 3 groups according to their CD4+T cell counts:<200×106/L,(200-350)×106/L and>350×106/L.Peripheral blood mononuclear cells(PBMC)were isolated.T cell proliferation index was measured by Ki-67 staining.T cell activation was detected by CD38 staining.The samples were analyzed by flow cytometry.The data were compared by one-way ANOVA.Results The percentage of Ki-67+cells in CIM+T ceils was 7.92%±4.37%in CD4+T cell<200×106/L group,which was significantly higher than those 0.39%d:0.24%in control group,2.61%±2.12%in(200-350)×106/k group and 2.65%±2.13%in>350 X106/L group(F=21.961,P<0.01).The percentage of Ki-67+cells in CD8+T ceils in CD4+T cells<200×106/L group was 2.87%±1.13%,which was also much higher than those in other 3 groups(0.15%±0.90%,1.40%±1.17%,1.22%±0.80%,respectively F=19.203,P<0.01).The Ki-67'CD4'T cells and Ki-67+CD8+T cells were inversely correlated with CD4+T cell counts(r=-0.654,r=-0.539,respectively;P<O.01),while were not correlated with viral load.The percentages of CD38+CD4+in CD4+T cells and CD38+CD8+in CD8+T cells were 44.14%±20.65%,50.64%±21.08%,respectively in CD4+T cells<200X 106/L group,and those were 10.22%±3.98%,6.46%±3.99%,respectively in control group,16.03%±10.20%,19.33%±13.43%,respectively in CD4+T cells(200-350)×106/Lgroup,13.69%±10.70%,16.98%±15.75%,respectively in CIM'T cells>350×106/L group(F=14.333,F=15.412,respectively;P<0.01).The expressions of Ki-67+ on CD4+ and CD8+T cells were positively correlated with CD38 expression(r=0.527,r=0.391,respectively;P=0.002).Conclusions The proliferation and activation of T lymphoeytes are enhanced during HIV/AIDS disease progression.And T eell activation may be the result of persistent immune activation.