OBJECTIVETo investigate the co-culture of keratinocytes with Malassezia isolates which cause the pityriasis versicolor with different color and to analyze the changes of cytokines associated with melanogenesis.

METHODSThe effects of Malassezia species with different proportions on the growth rate of keratinocytes was assessed with 5 g/L methyl thiazolyl tetrazolium (MTT). Co-culture of keratinocytes and Malassezia species were performed with isolates from hyer- and hypo-pigmentation areas of pityriasis versicolor. The supernatants were collected at different time points, and the changes of basic fibroblast growth factor (b-FGF), endothelin-1 (ET-1), nerve growth factor-beta (NGF-beta), interleukin-1alpha (IL-1alpha), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), stem cell factor (SCF) were recorded. Three control groups were established accordingly.

RESULTSWhen the ratio between keratinocytes and Malassezia species was lower than 1: 10, the growth rate of keratinocytes was not affected by Malassezia (P > 0.05). When the ratio was increased above 1:20, the growth rate of keratinocytes was significantly inhibited by Malassezia (P < 0.01). The secretions of IL-1alpha, IL-6, TNF-alpha, and ET-1 was significantly increased after the co-culture of keratinocytes and Malassezia (P < 0.01), while those of b-FGF, NGF-beta, and SCF had no significant changes (P > 0.05). Compared with the isolates from the hypo-pigmentation area, ET-1 induced by isolate from hyperpigmentation area significantly increased (P < 0.01).

CONCLUSIONWhen Malassezia isolates are co-cultured with keratinocytes, the secretions of cytokines associated with melanogenesis may differ from each other. ET-1 may play certain role in the hyper-pigmentation of pityriasis versicolor.

Cell Proliferation ; Cells, Cultured ; Cytokines ; biosynthesis ; Humans ; Keratinocytes ; cytology ; metabolism ; microbiology ; Malassezia ; isolation & purification ; physiology ; Melanins ; biosynthesis ; Tinea Versicolor ; microbiology

The three mammalian isoforms of transforming growth factor-beta (TGF-beta1, beta2, beta3) are potent regulators of cell growth, differentiation, and extracellular matrix deposition. To study their role in skin differentiation, we investigated the expression of TGF-beta isoforms on cell growth and differentiation induction of the human keratinocyte cell line, HaCaT by elevating the Ca2+ concentration. An ELISA and RT-PCR assay revealed secreted TGF-beta 1 protein and TGF-beta1 mRNA were increased during calci-um-induced differentiation. In contrast, major differences were seen for TGF-beta 2 and TGF-beta 3 mRNA which were decreased during differentiation, but TGF-beta 2 and TGF-3beta protein were not evident on an ELISA. These results suggest different functions for each TGF-beta isoforms in epidermal differentiation, such that TGF-beta 1 is associ-ated with the more differentiated state, and TGF-beta 2 and TGF-beta 3 may be associ-ated the more proliferated state.
Cell Differentiation/physiology ; Cell Line ; Gene Expression Regulation, Developmental/*physiology ; Humans ; Keratinocytes/*cytology/*physiology ; Protein Isoforms/metabolism ; Transforming Growth Factor beta/*metabolism

Our objective is to determine the quality of tissue engineered human skin via immunostaining, RT-PCR and electron microscopy (SEM and TEM). Culture-expanded human keratinocytes and fibroblasts were used to construct bilayer tissue-engineered skin. The in vitro skin construct was cultured for 5 days and implanted on the dorsum of athymic mice for 30 days. Immunostaining of the in vivo skin construct appeared positive for monoclonal mouse anti-human cytokeratin, anti-human involucrin and anti-human collagen type I. RT-PCR analysis revealed loss of the expression for keratin type 1, 10 and 5 and re-expression of keratin type 14, the marker for basal keratinocytes cells in normal skin. SEM showed fibroblasts proliferating in the 5 days in vitro skin. TEM of the in vivo skin construct showed an active fibrocyte cell secreting dense collagen fibrils. We have successfully constructed bilayer tissue engineered human skin that has similar features to normal human skin.
Fibroblasts/*cytology ; Keratinocytes/*cytology ; Mice, Nude ; Microscopy, Electron ; Microscopy, Electron, Scanning ; Quality Control ; Regeneration/physiology ; Skin/pathology ; Skin Transplantation/pathology ; Skin Transplantation/*standards ; Tissue Engineering/*standards

OBJECTIVETo investigate the effect of fetal bovine serum (FBS) on expression of pigment epithelium-derived factor (PEDF) in normal epidermal keratinocytes and dermal fibroblasts.

METHODSKeratinocytes and fibroblasts were incubated with 10% FBS. PEDF protein level in the cells was determined by immunofluorescence and Western blot.

RESULTSPEDF was localized mostly in the cytoplasm,while some in the nuclei. The distribution of PEDF in cytoplasm was in a granular pattern. 10% FBS increased the expression of PEDF both in keratinocytes and fibroblasts,but histamine and Phorbol 12-myristate 13-acetate (PMA) did not interfere the distribution of PEDF in cells.

CONCLUSION10% FBS can upregulate expression of PEDF in epidermal keratinocytes and dermal fibroblasts.

Animals ; Cattle ; Cells, Cultured ; Epidermis ; cytology ; metabolism ; Eye Proteins ; genetics ; metabolism ; Fetus ; Fibroblasts ; cytology ; metabolism ; Keratinocytes ; cytology ; metabolism ; Nerve Growth Factors ; genetics ; metabolism ; Serpins ; genetics ; metabolism ; Serum ; physiology ; Skin ; cytology ; metabolism ; Up-Regulation

Skin is the largest organ in human system and plays a vital role as a barrier against environment and pathogens. Skin regeneration is important in tissue engineering especially in cases of chronic wounds. With the tissue engineering technology, these skins equivalent have been use clinically to repair burns and wounds. Consented redundant skin samples were obtained from patients aged 9 to 65 years old. Skin samples were digested with dispase, thus separating the epidermis and the dermis layer. The epidermis layer was trypsinized and cultured in DKSFM in 6-well plate at 37 degrees C and 5% CO2. Once confluent, the culture were trypsinized and the cells were pooled. Cells were counted using haemacytometer. Doubling time and viability were calculated and analysed. From the result, we conclude that doubling time and viability of in vitro keratinocytes cultured in DKSFM media is not age dependant.
Age Factors ; Burns/physiopathology ; Burns/*therapy ; Cell Aging/*physiology ; Cell Division/physiology ; Cell Survival/physiology ; Chronic Disease ; Keratinocytes/*cytology ; *Skin Transplantation ; Statistics ; Tissue Engineering/*methods ; Wound Healing/physiology ; Wounds and Injuries/physiopathology ; Wounds and Injuries/*therapy

Antigens, CD34 ; metabolism ; Biomarkers ; metabolism ; Cell Differentiation ; physiology ; Hair Follicle ; cytology ; Humans ; Intramolecular Oxidoreductases ; metabolism ; Keratinocytes ; metabolism ; Melanins ; metabolism ; Melanocytes ; metabolism ; PAX3 Transcription Factor ; metabolism ; Stem Cells ; metabolism

The inactivation of p53 and p105RB by viral proteins or by mutations plays a key role in the oncogenesis of cervical carcinoma. The E6 and E7 proteins of HPV type 16 can bind to p53 and p105RB tumor suppressor gene products, respectively. In the present study, we tested a simple in vivo model that could explain the interactions between HPV E6 oncoprotein and p53 tumor suppressor protein. Our results showed that the life span of normal cervical epithelial cells was increased up to 4.5 times when transfected with expression vector containing E6/E7 ORF of HPV type 16. However, these cells did not divide after second crisis. Therefore, we employed an established human epidermal keratinocytes, RHEK-1. When transfected with an expression vector containing E6 ORF of HPV type 16, RHEK-1 cells showed anchorage independent growth character. When RHEK-E6 cells were transfected with wild type p53 expression vector, the growth rate of the RHEK-E6 cells was diminished. After 48 hours of transfection, many cells showed apoptotic signal but no more apoptotic signal was observed thereafter. These results suggested that the overexpression of the wild type p53 could overcome the dysfunction of the p53 on the cell cycle regulation imposed by E6 protein although not being of physiological condition.
Animal ; Base Sequence ; Cells, Cultured ; Cervix Uteri/*cytology ; Female ; Genes, p53/*physiology ; Human ; Keratinocytes/*cytology ; Mice ; Molecular Sequence Data ; Oncogene Proteins, Viral/genetics/*physiology ; Papillomavirus, Human/*genetics ; Support, Non-U.S. Gov't ; Transfection

Artemin is a neuronal survival and differentiation factor in the glial cell line-derived neurotrophic factor family. Its receptor GFRalpha3 is expressed by a subpopulation of nociceptor type sensory neurons in the dorsal root and trigeminal ganglia (DRG and TG). These neurons co-express the heat, capsaicin and proton-sensitive channel TRPV1 and the cold and chemical-sensitive channel TRPA1. To further investigate the effects of artemin on sensory neurons, we isolated transgenic mice (ARTN-OE mice) that overexpress artemin in keratinocytes of the skin and tongue. Enhanced levels of artemin led to a 20% increase in the total number of DRG neurons and increases in the level of mRNA encoding TRPV1 and TRPA1. Calcium imaging showed that isolated sensory neurons from ARTN-OE mice were hypersensitive to the TRPV1 agonist capsaicin and the TRPA1 agonist mustard oil. Behavioral testing of ARTN-OE mice also showed an increased sensitivity to heat, cold, capsaicin and mustard oil stimuli applied either to the skin or in the drinking water. Sensory neurons from wildtype mice also exhibited potentiated capsaicin responses following artemin addition to the media. In addition, injection of artemin into hindpaw skin produced transient thermal hyperalgesia. These findings indicate that artemin can modulate sensory function and that this regulation may occur through changes in channel gene expression. Because artemin mRNA expression is up-regulated in inflamed tissue and following nerve injury, it may have a significant role in cellular changes that underlie pain associated with pathological conditions. Manipulation of artemin expression may therefore offer a new pain treatment strategy.
Animals ; Hot Temperature ; Hyperalgesia ; metabolism ; Keratinocytes ; physiology ; Mice ; Mice, Transgenic ; Nerve Tissue Proteins ; genetics ; metabolism ; Nociceptors ; physiology ; Skin ; cytology ; TRPA1 Cation Channel ; TRPV Cation Channels ; metabolism ; Tongue ; cytology ; Transient Receptor Potential Channels ; metabolism

OBJECTIVETo investigate the mechanism involved in aging process of immortalized human keratinocyte (HaCaT) and primary human epidermis keratinocyte of adults (HEKa) irradiated by ultraviolet B(UVB).

METHODSHEKa and HaCaT were repeatedly exposed to UVB at a subcytotoxic level. SA-beta-Gal staining was performed to evaluate the senescence state; flow cytometry was applied to detect the changes of apoptosis, necrosis and cell cycle. Intracellular levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured by ELISA method. Western blot was performed to detect the expression pattern of redox protein p66Shc and RT-PCR was performed to determine the mRNA level of human telomerase reverse transcriptase (hTERT).

RESULTStrong positive SA-beta-Gal staining was observed in both HEKa cell and HaCaT cells after UVB irradiation. Apoptosis rate increased from (1.81 +/-0.25)% to (4.43 +/-0.28)% and necrosis rate increased from (0.05 +/-0.01)% to (0.10 +/-0.03)% in HaCaT cell, but no marked arrest of cell cycle was observed during UVB irradiation. As a contrast, apoptosis rate of in HEKa cells significantly increased from (0.65 +/-0.05)% to (59.53 +/-2.35)%, and the necrosis rate in HEKa cells also reached (3.89 +/-0.24)%(P<0.05). Growth arrest in G0/G1 phase was also found in HEKa cells. In both cell lines, intracellular level of SOD decreased and MDA increased remarkably after UVB exposure, and an increased expression of p66Shc protein was also observed. High level of hTERT mRNA was detected in HaCaT cells and UVB exposure had little effect on its expression.

CONCLUSIONThe stress-induced premature senescence (SIPS) in HaCaT and HEKa cell lines by UVB irradiation might be closely associated with increased intracellular levels of oxidative stress, not related to the telomerase expression.

Apoptosis ; Cell Line ; Cells, Immobilized ; radiation effects ; Cellular Senescence ; physiology ; radiation effects ; Humans ; Keratinocytes ; cytology ; radiation effects ; Malondialdehyde ; metabolism ; Skin ; cytology ; Superoxide Dismutase ; metabolism ; Telomerase ; genetics ; metabolism ; radiation effects ; Ultraviolet Rays ; beta-Galactosidase ; pharmacology

OBJECTIVETo explore the effect of millimeter wave (MW) at low power density on gap junctional intercellular communication (GJIC) in human keratinocytes (HaCaTs).

METHODSFluorescence recovery after photobleaching (FRAP) technique was employed to determine effect of 30.16 GHz MW exposure at 1.0 and 3.5 mW/cm(2) on GJIC with laser confocal scanning microscope.

RESULTSFRAP analysis revealed that 12-O-tetradecanoylphorbol-13-acetate (TPA) at a dose of 5 microg/L could inhibit GJIC in HaCaTs. Fluorescence recovery rate fell from (55 +/- 17)% in the controls to (34 +/- 13)% after photobleaching, with a very significant difference (P < 0.001). Exposure to MW alone for one hour at either 1.0 mW/cm(2) or 3.5 mW/cm(2) did not affect GJIC, with fluorescence recovery rates of (52 +/- 16)% and (50 +/- 17)%, respectively. GJIC suppression induced by TPA was weakened by MW combined with 5 microg/L TPA treatment for one hour, which could be partially recovered by exposure to 1.0 mW/cm(2) MW with fluorescence recovery rate of (47 +/- 16)%, P < 0.01, and fully recovered by exposure to 3.5 mW/cm(2) MW with fluorescence recovery rate of (50 +/- 16)%, P < 0.001, with a very significant difference.

CONCLUSIONSGJIC suppression induced by TPA could be eliminated or diminished by exposure to millimeter wave in HaCaTs.

Cell Communication ; drug effects ; radiation effects ; Cell Line ; Fluorescence Recovery After Photobleaching ; methods ; Gap Junctions ; drug effects ; physiology ; radiation effects ; Humans ; Keratinocytes ; cytology ; physiology ; Microwaves ; adverse effects ; Tetradecanoylphorbol Acetate ; pharmacology