Kinetics and mechanisms of hepatic acute phase response to subtotal partial hepatectomy and cultural impact on environmental hepatic end-stage liver injury in the homeless

Intoxication and liver damage induced by carbon tetrachloride (CCl(4)), aflatoxin B1, diabetes, and subtotal partial hepatectomy (PH(90)) in rats in which approximately 90% of the total hepatic tissue mass is surgically removed produces an acute-phase response (APR) whose initial stage prior to regression closely mimics the APRs associated with the life-threatening hepatic failure seen in the homeless.Rats treated by PH(90)were either healthy, CCl(4)-intoxicated, diabetic, or alflatoxin B1 (AFB1) intoxicated to the point of 75% liver insufficiency. It is well documented that high rates of mortality following PH(90)in aseptic rats could be minimized by supplementing drinking water with 20% glucose, organic components of L-15 medium and housing animals in cages maintained at 33-35;C. Aseptic rats showed a mild 20-30% decrease in APR proteins during the first 4-5 days following PH(90), while a maximal APR was noted 9-12 days post PH(90)and lasted for ~30 days when it returned to values close to those of healthy controls. This delay in hepatic APR of the remnant caudate lobe favoured replacement of lost basophilic clumps and ribosomes. The newly synthesized ribosomes of the nascent hepatocytes quantitatively maintained the APR signals of the injured caudate hepatocytes, and biosynthesized and released a typical spectrum of APR proteins. We suggest that massively injured liver has decoded an already stored and irreversible DNA-biochemical sequence of events in which priority is given to recovery of lost tissues by delaying an APR response to injury. In PH(90)of diabetic and CCl(4)-intoxicated rats, the hepatic dual functions of regeneration and APR processes associated with intoxication-initiated catabolic signals, created a heavy metabolic burden on the remnant caudate lobe leading to higher rates of mortality. APR of healthy rats to AFB1 parallels that of alpha-amanitin-induced intoxication. Similarly, within shorter time scale proportional to the severity of surgery, livers undergoing 75% partially hepatectomy (PH(75)) delayed both the onset and regression of APR.We are therefore led to believe that approaches other than liver transplantation should be considered as viable alternatives in the treatment of various acute and chronic liver diseases to avoid rejection and retransplantation. Scarcity of cadaveric liver has forced the medical community to investigate xenotransplantation with its unknown risks. Concomitantly, it is suggested that in view of the incalculable risks of indifference, the homeless must receive much improved medical care as we have found that two-dimensional immunoelectrophoretic assay of their serum is indicative of acute and chronic liver injury. The scientific and moral interrelationships of related matters are illuminated.     

Oral administration of immunoglobulin G-enhanced colostrum alleviates insulin resistance and liver injury and is associated with alterations in natural killer T cells

Insulin resistance and metabolic syndrome are chronic inflammatory conditions that lead to hepatic injury and non-alcoholic steatohepatitis (NASH). Bovine colostrum has therapeutic effects in a variety of chronic infections. However its effectiveness in NASH was never studied. Natural killer T (NKT) cells have been shown to be associated with some of the pathological and metabolic abnormalities accompanying NASH in leptin-deficient (ob/ob) mice. In the present study, we used hyperimmune bovine colostrum to treat hepatic injury and insulin resistance and we also assessed the effects on NKT cells. We used ob/ob mice that were fed for 6 weeks with either 0·1 mg bovine colostrum prepared from non-immunized cows, 0·1 mg hyperimmune colostrum raised against a bacterial lipopolysaccharide (LPS) extract or 0·001, 0·1 or 1 mg of immunoglobulin (Ig)G purified from hyperimmune colostrum (IgG-LPS). NKT cells were phenotyped by flow cytometry, and hepatic injury and insulin resistance were assessed by measuring fasting glucose levels, glucose tolerance tests and liver enzymes. Fat accumulation was measured in the liver and plasma. Oral administration of hyperimmune colostrums decreased alanine aminotransferase (ALT) serum levels and serum triglycerides compared to controls. Glucose intolerance was also improved by the hyperimmune colostrum preparations. These results were accompanied by a decrease in serum tumour necrosis factor (TNF)-α levels following oral treatment with 0·1 or 1 mg of IgG-LPS. The beneficial effects of hyperimmune colostrums were associated with an increase in the number of splenic NKT cells. These data suggest that oral administration of hyperimmune colostrum preparations can alleviate chronic inflammation, liver injury and insulin resistance associated with NASH.     

Role of c-Jun N-terminal kinase and p38/activation protein-1 in interleukin-1β-mediated type I collagen synthesis in rat hepatic stellate cells

Interleukin-1 (IL-1) may play a role in maintaining hepatic stellate cell (HSC) in activated state that is responsible for hepatic fibrogenesis. However, the signal transduction pathway that is stimulated by IL-1 in HSC remains to be fully elucidated. The aims of this study were to investigate the role of c-Jun N-terminal kinase (JNK) and p38/activation protein (AP-1) in IL-1β-mediated type I collagen synthesis in rat HSCs. Here, we show that IL-1β could activate JNK and p38 in a time-dependent manner, and that inhibition of the JNK pathway could increase collagen synthesis; however, inhibition of the p38 pathway could inhibit collagen synthesis. Furthermore, IL-1β activated AP-1 in a time-dependent manner in rat HSCs. These data demonstrate that L-1β could promote the synthesis of type I collagen in rat HSCs, and the JNK and p38/AP-1 pathways were involved in this process. In summary, IL-1β-induced collagen synthesis is possibly mediated by cytoplasmic JNK and p38/AP-1 pathways. Therefore, drugs that block the p38/AP-1 pathway may inhibit liver extracellular matrix synthesis and suppress liver fibrosis.     

Enhanced synthesis of cytokines by peripheral blood monocytes cultured in the presence of autoantibodies against U1-ribonucleoprotein and/or negatively charged molecules: implication in the pathogenesis of pulmonary hypertension in mixed connective tissue disease (MCTD).

An attempt was made to determine whether addition of purified autoantibodies against U1-ribonucleoprotein (RNP) and negatively charged molecules (cardiolipin and double-stranded (ds) DNA) to cultures of peripheral blood monocytes could enhance the synthesis of cytokines in patients with MCTD and normal healthy volunteers. It was found that: (i) at the baseline, levels of cytokines such as IL-1 alpha, IL-1 beta and IL-6 extracellularly released by or associated with monocytes were significantly higher in MCTD patients than in normal subjects; (ii) addition of antibodies against U1-RNP to cultures of MCTD monocytes resulted in a significant overall increase of the released and cell-associated IL-1 alpha, IL-1 beta and IL-6. On the other hand, addition of antibodies against cardiolipin or dsDNA to cultures of MCTD monocytes resulted in a significant increase of released and/or cell-associated IL-1 alpha and IL-1 beta; (iii) addition of these autoantibodies to cultures of normal monocytes resulted in a significant overall increase of released and cell-associated IL-1 alpha, IL-1 beta and IL-6. The extent of enhancement of cytokines released by or associated with monocytes was greater in normal subjects than in MCTD patients; (iv) a F(ab')2 preparation of autoantibodies against U1-RNP also enhanced the level of released and cell-associated IL-1 alpha. Our findings that both autoantibodies against U1-RNP and negatively charged molecules were able to enhance the synthesis of cytokines by monocytes suggest that these autoantibodies might cause derangement of endothelial cells and lead to proliferative vasculopathy, which is a characteristic of pulmonary hypertension in MCTD.     

Influence of an established acute phase response on the severity of experimental nephritis.

Small doses of lipopolysaccharide (LPS) induced an acute phase response (APR), and a number of studies have also shown that this greatly enhances the severity of glomerular injury in the heterologous phase of nephrotoxic nephritis (hNTN), an experimental model of anti-glomerular basement membrane (GBM) disease. Here, we examined the influence of pre-existing subclinical infection and raised APR, assessed by plasma alpha 2-macroglobulin (alpha 2-M) concentration, on the degree of injury in this model of nephritis. Studies were initially performed to determine the normal range of alpha 2-M in rats and its modulation by IL-6 and different doses of LPS. Plasma concentration of alpha 2-M was found to be variable and dependent on the weight of the rats. Single injections of either LPS or IL-6 had a comparable effect, and continuous perfusions of LPS caused a progressive increase in alpha 2-M which peaked at 48 h and declined gradually over 1 week. Following induction of nephritis with 10 mg of anti-GBM antibody, rats with raised alpha 2-M had 14 +/- 3 mg/24 h albuminuria compared with 4 +/- 1 mg/24 h in rats with normal alpha 2-M (P < 0.001, Wilcoxon). Injection of 20 mg anti-GBM antibody caused 36 +/- 11 mg/24 h albuminuria compared with 16 +/- 4 mg/24 h (P < 0.001), respectively. However, all these rats remained active and none of them died. In contrast, injection of 0.25 microgram LPS before induction of nephritis with 10 mg anti-GBM antibody, in rats with raised alpha 2-M, caused severe albuminuria (115 +/- 23 mg/24 h) compared with rats having normal levels of alpha 2-M (72 +/- 15 mg/24 h, P < 0.05). Furthermore, rats with raised alpha 2-M also had severe systemic manifestations characterized by pulmonary haemorrhage and extensive glomerular thrombosis, and many of them died. These results demonstrate the potential effect of pre-existing subclinical infection and raised APR on severity of glomerular injury which may affect the outcome of experimental studies.     

CCL3/MIP-1alpha is pro-inflammatory in murine T cell-mediated hepatitis by recruiting CCR1-expressing CD4(+) T cells to the liver

T cell-mediated hepatitis is associated with significant morbidity and mortality worldwide. Levels of C-C chemokine ligand 3/macrophage inflammatory protein-1alpha (CCL3/MIP-1alpha) are elevated in the serum of patients with T cell-mediated liver diseases, but its role is not fully understood. Con A-induced hepatitis is a murine liver-specific inflammation mediated by activated T cells and is driven by an up-regulation of the hepatic expression of IFN-gamma. In this study, we have used CCL3/MIP-1alpha gene-deficient mice to examine the role of CCL3/MIP-1alpha in the pathogenesis of Con A-induced hepatitis. We demonstrate a novel pro-inflammatory role for CCL3/MIP-1alpha since CCL3/MIP-1alpha deficiency significantly attenuated hepatic injury, both biochemically and histologically. Moreover, the recruitment of CCR1-expressing CD4(+) T cells to the liver after Con A treatment was strikingly attenuated by CCL3/MIP-1alpha deficiency. Correspondingly, hepatic IFN-gamma produced by the recruited CD4(+) T cells was significantly reduced by CCL3/MIP-1alpha deficiency during Con A-induced hepatitis. Furthermore, treatment of mice with a dual CCR1/CCR5 peptide antagonist, methionylated RANTES, also markedly reduced hepatic injury and decreased the numbers of CD4(+) T cells within the liver producing IFN-gamma during Con A-induced hepatitis. These findings demonstrate that blockade of the CCL3/MIP-1alpha-CCR1 pathway may represent a novel therapeutic target for treating T cell-mediated liver diseases.     

Characterization of 17 novel endoglin mutations associated with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia type 1 (HHT1) is a vascular dysplasia caused by mutations in the endoglin (ENG) gene and associated with epistaxis, telangiectases, and a high incidence of pulmonary arteriovenous malformations. To efficiently detect deletions and insertions, we optimized a quantitative multiplex polymerase chain reaction (QMPCR) analysis. We report 17 novel mutations, of which six were detected by QMPCR. Three deletions occurring in intronic sequences were associated with a single copy of exons 9a-14, exon 5, and exons 7-8, respectively. A transient 70kDa monomeric mutant protein resulted from the in-frame deletion of exons 7 and 8 but no mutant protein was present in the other cases. Deletion (in exon 10) or insertion (in exon 7) of two nucleotides, as well as a 1-bp deletion in the small exon 9a were found by QMPCR. Sequencing was required to detect single nucleotide deletions/insertions in exons 2, 5, 6, and 8. No mutant proteins were associated with these frame shift mutations. Two novel splice site mutations resulted in skipping of exons 2 and 4, respectively, while a previously reported intron 3 splice mutant was observed as a de novo mutation. We also report five novel nonsense and missense mutations, including one de novo. Review of the 80 HHT1 families reported to date indicates that 10% would not be resolved by sequencing and that an additional 25% could be revealed by QMPCR performed prior to sequencing. Thus the use of QMPCR accelerates genetic screening for HHT1 and resolves mutations affecting whole exons.     

Synchronous increase of four acute phase proteins synthesized by the same hepatocytes during the inflammatory reaction: a combined biochemical and morphologic kinetics study in the rat

The hepatic synthesis of four "acute phase reactants" (APR), i.e., fibrinogen, alpha 1-acid glycoprotein, alpha 2-macroglobulin, and haptoglobin has been investigated in rats suffering from turpentine-induced inflammation. To follow the change in the rates of synthesis of the four APR, their concentrations were measured by immunonephelemetry in both the plasma and the hepatic microsomal fraction at various times after injury. A synchronous increase in the concentrations of these four proteins was observed in the liver (maximum 24 hours) as well as in the plasma (maximum 40 hours) of the same animals. In parallel, the site of their synthesis was localized in liver sections by light and electron microscopy using direct immunoperoxidase labeling. Of the liver cells, only the hepatocytes were labeled. In the early period of the inflammatory reaction (10 to 16 hours), synthesizing cells were detected principally in the periportal zone, but later (24 hours), the labeled area was extended to nearly the entire hepatic lobule. When serial sections of liver were examined at that time, the same cells were found to contain simultaneously the four APR. Within the cells examined by electron microscopy, the four proteins were localized in the secretory pathway, i.e., rough and smooth endoplasmic reticulum, Golgi apparatus, and secretory vacuoles. Therefore, we conclude that: (1) the experimental inflammatory reaction induces a synchronous increase in the synthesis of four APR by the liver; (2) this increased synthesis apparently results from an increased number of synthesizing hepatocytes; (3) these cells have a preferential periportal localization; and (4) individual hepatocytes are not specialized in the synthesis of a single plasma protein.     

CHOP‐mediated hepcidin suppression modulates hepatic iron load

The liver is the central regulator of iron metabolism and accordingly, chronic liver diseases often lead to systemic iron overload due to diminished expression of the iron‐regulatory hormone hepcidin. To study the largely unknown regulation of iron metabolism in the context of hepatic disease, we used two established models of chronic liver injury, ie repeated carbon tetrachloride (CCl₄) or thioacetamide (TAA) injections. To determine the impact of CCAAT/enhancer‐binding protein (C/EBP)‐homologous protein (CHOP) on hepcidin production, the effect of a single TAA injection was determined in wild‐type and CHOP knockout mice. Furthermore, CHOP and hepcidin expression was assessed in control subjects and patients with alcoholic liver disease. Both chronic injury models developed a distinct iron overload in macrophages. TAA‐, but not CCl₄‐ injected mice displayed additional iron accumulation in hepatocytes, resulting in a significant hepatic and systemic iron overload which was due to suppressed hepcidin levels. C/EBPα signalling, a known hepcidin inducer, was markedly inhibited in TAA mice, due to lower C/EBPα levels and overexpression of CHOP, a C/EBPα inhibitor. A single TAA injection resulted in a long‐lasting (> 6 days) suppression of hepcidin levels and CHOP knockouts (compared to wild‐types) displayed significantly attenuated hepcidin down‐regulation in response to acute TAA administration. CHOP mRNA levels increased 5‐fold in alcoholic liver disease patients versus controls (p < 0.005) and negatively correlated with hepcidin expression. Our results establish CHOP as an important regulator of hepatic hepcidin expression in chronic liver disease. The differences in iron metabolism between the two widely used fibrosis models likely reflect the differential regulation of hepcidin expression in human liver disease. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Differences of peripheral inflammatory markers between mild cognitive impairment and Alzheimer's disease

Multiple pathogenic factors may contribute to the pathophysiology of Alzheimer's disease (AD). Peripheral markers have been used to assess biochemical alterations associated with AD and mild cognitive impairment (MCI) involved in its pathophysiology. The present study was conducted to evaluate inflammatory peripheral markers in elderly patients with MCI, patients with AD and normal elderly subjects. We measured plasma levels of different cytokines (IL-6, TNF-alpha and IFN-alpha) and platelet levels of cyclooxigenase-2 (COX-2) from 34 patients with MCI, 45 patients with AD and 28 age-matched control subjects. MCI and AD patients showed similarities in TNF-alpha and COX-2 levels, and differences in IL-6 and INF-alpha. Whereas augmented IL-6 levels have been found in AD patients, a significant increase in INF-alpha has been detected only in patients with MCI possibly associated with the depression stage frequently found in cognitive impairment. In conclusion, inflammatory response may be an early factor in AD development and these changes in circulating markers are possibly related to the progression of MCI to AD.     

Early induction of IL-1 receptor antagonist (IL-1Ra) in infants and children undergoing surgery.

The cytokine response to injury or trauma is of interest in terms of both its mediation of the acute phase response and its possible relation to the immunological depression observed after major surgery. In this study, the production of cytokines IL-1 beta, tumour necrosis factor-alpha (TNF-alpha), IL-6 and the naturally occurring inhibitor of IL-1, IL-1Ra, have been investigated in infants and children undergoing Swenson's pull-through operation for Hirschsprung's disease. Samples of peripheral blood were taken before, during and after surgery for the measurement of cytokines. IL-1Ra levels increased significantly (P < 0.01) at 2 h after commencement of surgery, with maximal levels for individual patients being attained between 3 h and 5 h (range 7.6-67.9 ng/ml). The mean level of IL-1Ra was maximal (26.2 ng/ml) at 5 h and returned to baseline levels between 24 h and 72 h. There were no changes observed in the circulating levels of IL-1 beta in nine out of 11 patients following commencement of surgery. TNF-alpha levels did not increase in any of the patients studied. IL-6 levels increased significantly (P < 0.02) 3 h after commencement of surgery, reaching maximum concentrations at 24 h (range 20-670 pg/ml), with levels falling between 48 h and 72 h. This study demonstrates, in vivo, the independent induction of IL-1Ra without a concomitant increase of IL-1 beta levels after major surgery. It also shows that IL-1Ra is the earliest cytokine produced in response to surgical stress.     

Enhanced Cytokine Synthesis of Leukocytes by a β-Glucan Preparation, SCG, Extracted from a Medicinal Mushroom, Sparassis crispa

Sparassis crispa is edible mushroom recently cultivable in Japan. It contains significantly high content (∼40%) of 6-branched 1,3-β-D-glucan showing antitumor activity in mice. We recently purified a β-glucan preparation designated as “SCG.” It was considered worth while to test SCG in vitro with whole blood collected from human volunteers. The present study is focusing on the cytokine productivity of SCG in an in vitro human system. The following results were observed: (i) SCG dose dependently enhanced IL-8 synthesis of whole blood cell culture of human peripheral blood. (ii) IL-8 synthesis was enhanced in both PBMC and PMN cultures. (iii) IL-8 synthesis was induced in the culture with autologous plasma, but significantly reduced after 56°C treatment. (iv) The activity was also weak in heat inactivated fetal calf serum (FCS). (v) A complement fragment, C5a, was released by SCG dependently upon dose and kinetics. (vi) Anti-SCG natural antibody was detected in human plasma. From these facts, SCG was observed to have the capacity to activate human leukocytes and related immune system.     

太子参多糖减轻高脂诱导的小鼠肝脏胰岛素抵抗

目的:通过研究太子参多糖(Radix Pseudostellariae polysaccharide,RPP)减轻高脂肪诱导肝脏胰岛素抵抗的作用,探寻其主要影响因素及发生的分子机制。方法:随机将C57BL/6J小鼠分为低脂饲料对照组(LFD组)和高脂饲料组(HFD组),16周后,经腹腔注射丙酮酸耐量试验(IPPTT)确定胰岛素抵抗糖代谢紊乱模型成功后,开始进行含RPP(500 mg/kg)的高脂饲料干预(HFD+RPP组),连续干预4周之后,检测丙酮酸耐量以及肝脏组织和线粒体丙二醛(MDA)含量。同时采用Western blot法检测肝脏组织中p-AKT(Ser473/Thr308)、p-AMPK、核因子E2相关因子2(Nrf2)、NQO1和IκBα的蛋白水平变化。结果:经RPP干预后,模型组小鼠血糖水平明显降低;肝脏和线粒体的MDA水平显著降低;肝脏组织p-AKT及p-AMPK的蛋白水平明显增高;NQO1、HO-1和IκBα蛋白水平也同时上调。结论:太子参多糖能够有效抑制高脂肪诱导的C57BL/6J小鼠高血糖作用,其机制可能与改善肝脏胰岛素信号转导,并减轻氧化应激反应,同时激活Nrf2信号通路及抑制肝脏炎症信号激活作用有关。     

Synergistic antiviral effect of a combination of mouse interferon-alpha and interferon-gamma on mouse hepatitis virus

Although interferon (IFN)-alpha and IFN-gamma have been reported to exhibit a synergistic antiviral effect through the different signaling pathways in vitro, their therapeutic efficacy is not well defined in vivo. The current study was carried out to investigate the combined antiviral effect in a model of mouse hepatitis virus Type 2 (MHV-2) infection, in which fulminant hepatitis is developed. MHV-2 was injected intraperitoneally into 4-week-old ICR mice, IFN or the vehicle was administered intramuscularly for 5 days, and the antiviral effect was evaluated based on survival periods, liver histology, serum alanine transaminase (ALT) levels, and MHV-2 virus titers in the liver tissues. The animals in the group treated with a combination of IFN-alpha and IFN-gamma survived for longer periods than the groups treated with IFN-alpha alone and IFN-gamma alone (IFN-alpha 10(3) (IU/mouse)/-gamma 10(3) vs. IFN-alpha 10(3), P < 0.005; IFN-alpha 10(3)/-gamma 10(3) vs. IFN-gamma 10(3), P < 0.001). This is consistent with the lower levels of hepatocellular necrosis and serum ALT and the decreased titers of MHV-2 virus in the liver tissues (48 hr, P < 0.001; 72 hr, P < 0.001). These findings indicate that a combination of IFN-alpha and IFN-gamma exhibits a synergistic antiviral effect on MHV-2 infection. The biology of MHV-2 is quite different from that of human hepatitis viruses; however, these results suggest the beneficial combined therapy of IFN-alpha and IFN-gamma for the treatment of human viral hepatitis.     

Dysregulation of hepatic cAMP levels via altered Pde4b expression plays a critical role in alcohol‐induced steatosis

Alcohol‐induced hepatic steatosis is a significant risk factor for progressive liver disease. Cyclic adenosine monophosphate (cAMP) signalling has been shown to significantly regulate lipid metabolism; however, the role of altered cAMP homeostasis in alcohol‐mediated hepatic steatosis has never been studied. Our previous work demonstrated that increased expression of hepatic phosphodiesterase 4 (Pde4), which specifically hydrolyses and decreases cAMP levels, plays a pathogenic role in the development of liver inflammation/injury. The aim of this study was to examine the role of PDE4 in alcohol‐induced hepatic steatosis. C57BL/6 wild‐type and Pde4b knockout (Pde4b^?/?) mice were pair‐fed control or ethanol liquid diets. One group of wild‐type mice received rolipram, a PDE4‐specific inhibitor, during alcohol feeding. We demonstrate for the first time that an early increase in PDE4 enzyme expression and a resultant decrease in hepatic cAMP levels are associated with the significant reduction in carnitine palmitoyltransferase 1A (Cpt1a) expression. Notably, alcohol‐fed (AF) Pde4b^?/? mice and AF wild‐type mice treated with rolipram had significantly lower hepatic free fatty acid content compared with AF wild‐type mice. Importantly, PDE4 inhibition in alcohol‐fed mice prevented the decrease in hepatic Cpt1a expression via the Pparα/Sirt1/Pgc1α pathway. These results demonstrate that the alcohol‐ induced increase in hepatic Pde4, specifically Pde4b expression, and compromised cAMP signalling predispose the liver to impaired fatty acid oxidation and the development of steatosis. Moreover, these data also suggest that hepatic PDE4 may be a clinically relevant therapeutic target for the treatment of alcohol‐induced hepatic steatosis. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Dexamethasone affects cytokine-mediated adhesion of HL-60 human promyelocytic leukemia cells to cultured dermal microvascular endothelial cells

Leukocyte endothelial adhesion (LEA) is the prelude to a complex cascade of reactions following an immunological challenge. Recently, LEA has been implicated in the molecular basis of several dermatological disorders. While the role of proinflammatory cytokines, such as interleukin-1 beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), in LEA has been investigated using nondermal models, limited data exist regarding their effects on LEA in dermal models. This study shows that cotreatment of cultured human dermal endothelial cells (CADMEC) with IL-1beta and TNF-alpha resulted in a marked increase in the adherence of human promyelocytic leukemia (HL-60) cells to CADMEC and an increase in expression of intercellular adhesion molecule-1 and E-selectin. Pretreatment of CADMEC with dexamethasone, a long-lasting glucocorticoid, resulted in a decrease in both HL-60 cell adhesion to CADMEC and adhesion molecule expression. Taken together, these data demonstrate that LEA may play a role in inflammatory skin conditions and in the mechanisms underlying the potential use of glucocorticoids as a treatment option.