In Vitro Effects of 1,25-Dihydroxyvitamin D3 on the Production of Interleukin-1alpha by Ultraviolet B Irradiation in Cultured Human Keratinocyte Cell Line HaCaT Cells / 대한피부과학회지

BACKGROUND: Keratinocyte-derived interleukin-1(IL-1)alpha is one of the key cytokines in initiation of cutaneous inflammation. Release of IL-1alpha from human keratinocytes may be induced by proinflammatory stimuli including ultraviolet B(UVB) irradiation, and subsequently, keratinocyte-derived IL-1alpha may exert numerous paracrine and autocrine effects. 1,25-dihydroxyvitamin D3(1,25(OH)2D3) is involved in the regulation of keratinocyte proliferation and differentiation and is also recognized to have immunoregulatory properties such as an antiinflammatory effect. OBJECTIVE: The purpose of this study was to investigate the in vitro effects of 1,25-(OH)2D3 on the production of IL-1alpha by UVB irradiation in cultured human keratinocyte cell line HaCaT cells. RESULTS: are summerized as follows; 1. The vialility of cultured HaCaT cells measured by MTS assay at 24 hours after UVB irradiation was significantly reduced at the doses of above 100 mJ/cm2 of UVB(p<0.05). 2. The secretion of IL-1alpha by HaCaT cells was significantly increased at the doses of above 30 mJ/cm2 of UVB(p<0.05). UVB irradiation could not influence on the secretion of IL-1beta by HaCaT cells. 3. At the concentrations of 10-8M and 10-6M of 1,25(OH)2D3, the production of IL-1alpha by HaCaT cells(48 hours after 100 mJ/cm2 UVB irradiation) was significantly inhibited in both culture supernatants and cell lysates(p<0.05). CONCLUSION: UVB irradiation increased the production of IL-1alpha by HaCaT cells and this stimulatory effect on the production of IL-1alpha induced by UVB irradiation was suppressed by 1,25-(OH)2D3. Calcipotriol(MC-903) had similar suppressive effect on the production of IL-1alpha induced by UVB irradiation in HaCaT cells to that of 1,25(OH)2D3.

The Effects of CD11c/CD18 and CD14 Blocking on Lipopolysaccharide-induced Endotoxemia

We studied the morphologic changes and the expression of cytokines of major organs by blocking CD14 and CD11c/CD18, which are known to be receptors of lipopolysaccharide (LPS), in the LPS induced endotoxemic mice. In 2 and 8 hours after initial intraperitoneal injection of 10 mg/kg of LPS into the mice, 500 microgram/kg of anti-CD14 antibody (Ab) and/or the same dosage of the anti-CD11c/CD18 Ab were administered intravenously, respectively or concomitantly. Under the light microscope, the LPS only and the LPS with the anti-CD14 Ab injected groups (group 1 and 2) showed marked acute inflammation in the organs, especially in the lung and liver, but the LPS with the anti-CD11c/CD18 Ab only or with both anti-CD14 and anti-CD11c Abs injected groups (group 3 and 4) revealed only mild acute inflammation. Under the electron microscope, there was marked inflammation in the group 1 and 2 such as marked infiltration of neutrophils, monocytes/ macrophages, lymphocytes, aggregation of platelets, and marked edematous change of endothelial cells with separation from the basement membrane. However in the group 3 and 4, there was only mild inflammation such as mild infiltration of neutrophils in the tissue or aggregation of neutrophils in the capillaries and sinusoids with mild endothelial swelling. The expressions of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1alpha (IL-1alpha), detected by RT-PCR method, was remarkable in the group 2, but minimal in the group 3 and 4. We conclude that blocking the CD11c/CD18 with anti-CD11C/CD18 Ab is effective for the prohibition of biologic reactions and diminution of the inflammation induced by the LPS, even in the LPS induced endotoxemia.

Inhibitory Effects of Dexamethasone on Production IL-1alpha and TNF-alpha in Peripheral Blood Mononuclear Cells

PURPOSE: IL-1alpha and TNF-alpha have a seminal role in the intial events of inflammation. An area of intense interest is the assessment of new therapeutic modalities that regulate inflammatory response in acute bacterial infection. We conducted this study to compare the inhibitory effects of dexamethasone on the secretion of proinflammatory cytokines, such as IL-lalpha and TNF-alpha from cord blood mononuclear cells(MC) to those of adult blood MC during stimulation with S. aureus TSST-1 and E. coli LPS. METHODS: MC were isolated by differential centrifugation on Ficoll-Hypaque gradients. Each MC were incubated with TSST-1(2ug/ml) or LPS(0.2ug/ml), with various concentrations of dexamethasone for 72hr. And the other MC were incubated with TSST-1 or LPS, using the same concentration of dexamethasone, which was added 4hr before or simultaneously or 4hr, 24hr, 48hr after the stimulation. Concentration of IL-1alpha and TNF-alpha was measured by ELISA kit. RESULTS: Dexamethasone showed significant inhibitory effects on secretion of IL-1alpha and TNF-alpha. In comparison with both cytokines, secretion of IL-1alpha was suppressed more severely than TNF-alpha. In comparison with each stimulators, inhibition of TSST-1 induced cytokines production was greater than LPS. There was no difference between adult and cord blood MC. When dexamethasone was added to MC 4hr before the stimulation, it had the best inhibitory effects on the production of proinflammatory cytokines. CONCLUSION: Proinflammatory cytokine production in cord and adult blood MC were inhibited by dexamethasone in a dose-dependent manner. Early treatment of dexamethasone is more effective and can be used for modulating or suppressing excessive proinflammatory cytokine production in acute bacterial infection.

Inhibitory Effects of Actinomycin-D and Pentoxifylline on the Production of IL-1alpha and TNF-alpha by Human Cord and Adult Blood Mononuclear Cells

PURPOSE: An area of intense intrest is assessment of new therapeutic modalities that regulate the inflammatory response in acute bacterial infection is proving to be an area of interest these days. So we conducted this study to compare the inhibitory effects of actinomycin-D and pentoxifylline on the production of IL-lalpha and TNF-alpha from cord blood mononuclear cells (MC) to those from adult blood MC stimulated with S. aureus toxic shock syndrome toxin (TSST)-1 and E. coli lipopolysaccharide (LPS). METHODS: Cord and adult blood MC were isolated by differential centrifugation on Ficoll-Hypaque gradients. Each mononuclear cells were incubated with TSST-1 (2 microgram/ml) or LPS (0.2 microgram/ml), simultaneously with various concentrations of actinomycin-D or pentoxifylline added for inhibition. Concentration of interleukin-1alpha (IL-lalpha) and tumor necrosis factor-alpha (TNF-alpha) were measured by means of ELISA. RESULTS: In comparison with each inhibitory drug, actinomycin-D showed more potent inhibitory effects on the production of IL-1alpha and TNF-alpha from adult and cord blood MC stimulated by TSST-1 and LPS, than pentoxifylline (P<0.05). There was no difference between adult and cord blood MC. In comparison with each stimulator, inhibition of TSST-1 induced cytokines production with actinomycin-D was greater than pentoxifylline, in contrast to inhibition of LPS induced cytokines production with pentoxifylline which was greater than actinomycin-D in adult blood MC (P<0.05). CONCLUSION: Proinflammatory cytokine production in cord and adult blood MC were inhibited by each drug in the same manner except, the inhibition of pentoxifylline for LPS in cord blood MC. So it is possible that these drugs can be used to modulate or suppress excessive proinflammatory cytokine production in acute bacterial infection.

Production of Interleukin-1alpha and Tumor Necrosis Factor-alpha by Human Cord and Adult Blood Mononuclear Cells Stimulated by TSST-1 and LPS

PURPOSE: Immature immunological defens mechanism in the neonate may contribute to the high susceptibility to overwhelming sepsis. S. aureus TSST-1 and E. coli LPS known as one of the important pathogens of septic shock or toxic shock induce massive release of various cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1alpha (IL-1alpha) produced from peripheral blood mononuclear cells (PBMC). In contrast, limited information has been provided so far concerning the capacity of cytokine production from neonatal immune cells. METHODS: This study was conducted to compare the secretion of proinflammatory cytokines, such as IL-l and TNF-alpha from cord blood PBMC to those from adult blood PBMC stimulated by S. aureus TSST-1 and E. coli LPS. RESULTS: 1) IL 1-alpha was secreted in a time-dependent manner from cord & adult blood PBMC stimulated with several cytokine inducers, and LPS stimulated adult & cord blood PBMC secreted IL 1-alpha in a dose-dependent manner. 2) TNF-alpha secretion from cord blood PBMC stimulated with LPS and IFN- significantly decreased in a time dependent manner, but not from adult PBMC. And secretion of TNF- from cord blood PBMC reached the highest level 24 hours after stimulated with LPS or IFN-gamma. The secretion of TNF-alpha from adult blood PBMC showed similar pattern to those from cord blood PBMC, but higher than cord blood PBMC. 3) IL-1alpha & TNF-alpha secretion from cord & adult blood PBMC stimulated with TSST-1 had no significant difference except in TNF- secretion by TSST-1 at 96 hours. 4) The secretion of IL-1alpha from adult PBMC stimulated with LPS showed higher and longer than that from cord blood PBMC. 5) IL-1alpha & TNF-alpha secretion from cord & adult blood PBMC stimulated with IFN-gamma had no significant difference. CONCLUSIONS: In summary, proinflammatory cytokines such as IL-1alpha, TNF-alpha in cord blood PBMC were secreted in a time dependent manner, but the amounts of IL-1alpha and TNF-alpha secretion were lesser than those of adult blood PBMC, especially stimulated by LPS. These results suggest that increased susceptibility to infection in neonatal period may be partially from a functional immaturity of cord blood mononuclear cells.