Objective To evaluate the serum histamine-releasing activity of patients with chronic urticaria and explore the pathogenesis of chronic urticaria. Methods Sixty-two chronic urticaria patients were studied by using in vivo autologous serum skin test (ASST) and in vitro histamine release assay of human cutaneous mast cells incubated with the patient′s sera. Results Twenty-four out of 62 patients showed a wheal response to autologous serum (38.71%). Sera from patients with chronic urticaria released a significantly higher quantity of histamine compared with the control subjects (P

0.05).ASST+ patients had larger wheals(P

Objective To study the effects of the IL-1 receptor antagonist (IL-1Ra) on matrix metalloproteinase 1 (MMP-1) expression in UV-irradiated fibroblasts. Methods Simulating the impact of environmental ultraviolet (UV) light on human skin, UVA-irradiated human fibroblasts were cultured in medium obtained from UVB-irradiated HaCaT cells. MMP-1 was detected by ELISA in the culture medium of fibroblasts. After treatment with IL-1Ra, the mRNA expression levels of C-Jun, C-Fos and GAPDH (internal control) of fibroblasts were measured by real-time fluorescent quantitative RT-PCR. Results Production of MMP-1 by UVA (10 J/cm2)-irradiated fibroblasts was increased in culture medium from UVB-irradiated HaCaT cells. The fibroblasts produced significantly higher levels of MMP-1 in culture medium from HaCaT cells treated without UVB than those with 15 mJ/cm2 UVB (t = 8.413,P= 0.014). However, IL-1Ra inhibited MMP-1 production of fibroblasts in a dose-dependent manner. Standard curves of real-time fluorescent quantitative RT-PCR showed a linear correlation between the copy number and the threshold cycle (Tc). Melting curves confirmed the specificity of PCR products. The original copy numbers of C-Jun and C-Fos as well as the ratios of the numbers to the GAPDH copy number showed that IL-1Ra inhibited the C-Jun mRNA expression of fibroblasts in a dose-dependent manner but had no significant effects on C-Fos mRNA expression. Conclusions The culture medium from UVB-irradiated HaCaT cells can promote MMP-1 production by UVA-irradiated fibroblasts. IL-1Ra reduces MMP-1 production via inhibition of C-Jun mRNA expression.

In order to investigate the effects of cis-UCA on cell -mediated immunity, we established a murine model of DTH response to DNP6OVA which is indicated by the increasing in the ear thickness of the mouse after resensitization, compared with those of the mouse injected with 200 g cis - UCA and trans -UCA intraperitoneally (i. p. ). The average of the increasing in ear thickness of each group was 9. 1 1. 13 10-2 mm (n=8, the number of ears) for the group administrated with cis-UCA; 17. 45 0. 88 10 - 2 mm (n= 8) for the group administrated with trans-UCA ; 16. 43 + 1. 83 10 - 2 mm(n= 7) for control group. It is suggested that there are immunosuppression of DTH response to DNP6OVA in mouse administrated with ets-UCA and no effecs of trans-UCA on this response.

Objective To establish a cell line with repressed expression of p53 by transfecting a plasmid construct expressing short hairpin RNA(shRNA)targeting p53 into human skin fibroblasts(HSFs),and to evaluate the effect of repression of p53 expression on the senescence in HSFs.Methods The eukaryotic expressing plasmid pGCsi-p53 containing shRNA targeting p53 gene was transfected into HSFs with lipofectamine.Subsequently,the cells were selected by G418,and resistant cell clones were chosen and expanded.Reverse transcription-PCR and real time fluorescence-based quanitative PCR were performed to determine the expression of p53 gene,and Western blot to detect the expression of p53 protein in HSFs.The senescence in HSFs was evaluated by SA β-gal staining,and cell proliferation by methyl thiazolyl tetrazolium(MTT)assay.Results A HSF clone with repressed expression of p53 was established successfully.The expressions of p53 mRNA and protein were downregulated in transfected HSFs compared with untransfected HSFs(0.09 ± 0.03 vs.0.32 ± 0.04,0.11 ± 0.04 vs.0.84 ± 0.05,both P ＜ 0.01).The percentage of senescent cells was 13.47％ ± 1.01％ in the transfected HSFs,significantly lower than that in untransfected HSFs(18.10％ ± 0.66％,P ＜ 0.05).As MTT assay showed,the proliferation was accelerated in transfected HSFs compared with untransfected HSFs(P ＜ 0.05).Conclusions The repression of p53 expression decelerates the senescence in HSFs,but promotes the proliferation of HSFs.

Objective To study the immunosuppression mechanism induced by ultraviolet (UV) and cis-urocanic acid. Method The auto lymphocyte proliferation test with Langerhans＇ cell (LC) in guinea -pig was performed. Results In exposure to low dose of UVB (25 J/m2) radiation, the inhibition rate of lymphocyte proliferation stimulated by LC was 10. 5%, the inhibition rates of UVB radiation in doses of 50 J/m2 and 100 J/m2 were 22.4% or 50%, respectively. The lymphocyte proliferation was almost completely suppressed by200J/m2 UVB radiation, while the inhibition of LC function by cis-urocanic acid was weak. Conclusion UVB significantly inhibits LC auto -stimulation in dose -dependent way, which may play an important role in UVB induced immunosuppression.

0.25)levels in the two groups.In the group treated with42mJ/cm 2 UVB irradiation followed by the addition of EGCG,the numbers of apoptotic and dead cells and Fas mRNA were decreased,but bcl-2protein was increased.Conclusions Low dosage of UVB irradiation could induce apoptosis of keratinocytes.High dosage of UVB irradiation might result in cell death.EGCG could reduce UVB-induced apoptosis of keratinocytes by increasing bcl-2protein and decreasing Fas mRNA.

Objective To explore the inhibitory action of antisense c-jun oligodeoxynucleotides(ODN) on matrix metalloproteinase(MMP) expression of fibroblasts induced by ultraviolet B (UVB). Methods The c-jun and c-fos protein expression induced by UVB were measured by Western blot. The mRNA expression of c-jun was determined by reverse transcriptase polymerase chain reaction (RT-PCR) after transfection with c-jun antisense ODN. The pro-MMP-1 and MMP-3 synthesis of fibroblasts was measured by ELISA after treatment with UVB and antisense c-jun ODN. Results The UVB-induced c-jun protein expression of fibroblasts increased to 1.8, 2.6, 3.3 times compared with that of non-irradiated controls,while there was no significant change in c-fos protein expression. The pro-MMP-1 and MMP-3 synthesis induced by UVB irradiation increased obviously. After transfection with different concentrations of c-jun antisense ODN, the UVB-induced c-jun mRNA expression could be significantly inhibited(P

Objective To investigate the protective effect of aloin on inducible nitric oxide synthase (iNOS) and nuclear factor kappa B (NF-kB) synthesis of HaCat cells induced by ultraviolet B (UVB) irradiation. Methods The proliferation of HaCat cells was measured by MTT method. iNOS mRNA was detected by reverse transcriptase polymerase chain reaction (RT-PCR). NO production was assessed by spectrophotometric method, and expression of NF-kB P65 was measured by immunofluorescent staining. Results After irradiation with 30 mJ/cm~2 of UVB, proliferation of HaCat cells was decreased, and NO generation and iNOS mRNA synthesis in HaCat cells were increased. UVB irradiation could also activate the expression of NF-kB P65 and promote its translocation into nucleus. NO generation and iNOS mRNA synthesis were markedly down-regulated in a dose-dependent manner by pre-treatment with different concentrations of aloin. The activation of NF-kB P65 was inhibited while the proliferation of HaCat cells was increased. All the difference reached statistical significance (P

Cao reported that melagenine extracted from human placenta was effective in the clinical treatment of vitiligo, to elucidate the possible mechanism involved, melagenine and placenta peptide were added to melanocytes in the culture, and the culture without melagenine as control. The results obtained by MTT showed that melagenine can stimulate melanoeyte proliferation, its promoting rate was 42.5%, while placenta peptide got a promoting rate of 5.9%, the difference was significant (P