Resveratrol Prevents Endothelial Cells Injury in High-Dose Interleukin-2 Therapy against Melanoma

Immunotherapy with high-dose interleukin-2 (HDIL-2) is an effective treatment for patients with metastatic melanoma and renal cell carcinoma. However, it is accompanied by severe toxicity involving endothelial cell injury and induction of vascular leak syndrome (VLS). In this study, we found that resveratrol, a plant polyphenol with anti-inflammatory and anti-cancer properties, was able to prevent the endothelial cell injury and inhibit the development of VLS while improving the efficacy of HDIL-2 therapy in the killing of metastasized melanoma. Specifically, C57BL/6 mice were injected with B16F10 cells followed by resveratrol by gavage the next day and continued treatment with resveratrol once a day. On day 9, mice received HDIL-2. On day 12, mice were evaluated for VLS and tumor metastasis. We found that resveratrol significantly inhibited the development of VLS in lung and liver by protecting endothelial cell integrity and preventing endothelial cells from undergoing apoptosis. The metastasis and growth of the tumor in lung were significantly inhibited by HDIL-2 and HDIL-2 + resveratrol treatment. Notably, HDIL-2 + resveratrol co-treatment was more effective in inhibiting tumor metastasis and growth than HDIL-2 treatment alone. We also analyzed the immune status of Gr-1+CD11b+ myeloid-derived suppressor cells (MDSC) and FoxP3+CD4+ regulatory T cells (Treg). We found that resveratrol induced expansion and suppressive function of MDSC which inhibited the development of VLS after adoptive transfer. However, resveratrol suppressed the HDIL-2-induced expansion of Treg cells. We also found that resveratrol enhanced the susceptibility of melanoma to the cytotoxicity of IL-2-activated killer cells, and induced the expression of the tumor suppressor gene FoxO1. Our results suggested the potential use of resveratrol in HDIL-2 treatment against melanoma. We also demonstrated, for the first time, that MDSC is the dominant suppressor cell than regulatory T cell in the development of VLS

Combined deficiency in CD44 and Fas leads to exacerbation of lymphoproliferative and autoimmune disease

Patients with mutations in Fas develop autoimmune lymphoproliferative disease (ALPS), While their family members with similar mutations are often normal, thereby suggesting that additional factors may play a role in the development of ALPS. In the current study, we tested the role of CD44 in the development of lymphoproliferative disease by generating CD44 -/-/Fas -/-mice, which failed to express CD44 and Fas, and compared them to CD44 +/+/Fas -/- mice that expressed CD44, but not Fas. The results showed that CD44 -/-/Fas -/- mice developed a more severe lymphoproliferative and autoimmune disease when compared to CD44 +/+/Fas -/- mice. This was indicated by increased numbers of cells in their lymph nodes, and a greater proportion of B220 +CD4 -CD8 - (double-negative) T cells as well as antibodies against single-stranded DNA and chromatin. The heightened severity of lymphoproliferative disease seen in CD44 -/-/Fas -/- mice correlated with increased resistance of T cells, but not B cells, to undergo activation-induced cell death (AICD). The current study suggests that deficiency in CD44 in combination with a defect in one of the molecules involved in the death receptor family such as Fas can further down-regulate AICD, and exacerbate the lymphoproliferative and autoimmune disease.close7

High-molecular-weight hyaluronan is a novel inhibitor of pulmonary vascular leakiness

Endothelial cell (EC) barrier dysfunction results in increased vascular permeability, a perturbation observed in inflammatory states, tumor angiogenesis, atherosclerosis, and both sepsis and acute lung injury. Therefore, agents that enhance EC barrier integrity have important therapeutic implications. We observed that binding of high-molecular-weight hyaluronan (HMW-HA) to its cognate receptor CD44 within caveolin-enriched microdomains (CEM) enhances human pulmonary EC barrier function. Immunocytochemical analysis indicated that HMW-HA promotes redistribution of a significant population of CEM to areas of cell-cell contact. Quantitative proteomic analysis of CEM isolated from human EC demonstrated HMW-HA-mediated recruitment of cytoskeletal regulatory proteins (annexin A2, protein S100-A10, and filamin A/B). Inhibition of CEM formation [caveolin-1 small interfering RNA (siRNA) and cholesterol depletion] or silencing (siRNA) of CD44, annexin A2, protein S100-A10, or filamin A/B expression abolished HMW-HA-induced actin cytoskeletal reorganization and EC barrier enhancement. To confirm our in vitro results in an in vivo model of inflammatory lung injury with vascular hyperpermeability, we observed that the protective effects of HMW-HA on LPS-induced pulmonary vascular leakiness were blocked in caveolin-1 knockout mice. Furthermore, targeted inhibition of CD44 expression in the mouse pulmonary vasculature significantly reduced HMW-HA-mediated protection from LPS-induced hyperpermeability. These data suggest that HMW-HA, via CD44-mediated CEM signaling events, represents a potentially useful therapeutic agent for syndromes of increased vascular permeability

Strain-specific differences in perivascular inflammation in lungs in two murine models of allergic airway inflammation

Histological data show perivascular recruitment of inflammatory cells in lung inflammation. However, the process of perivascular inflammation is yet-to-be characterized in any systematic manner at cell and molecular levels. Therefore, we investigated impact of genetic background on perivascular inflammation in acute or chronic airway inflammation in different strains of mice. Further, to address molecular mechanisms of perivascular inflammation, we examined immunohistochemical expression of vascular adhesion protein-1 (VAP-1) in chronic airway inflammation. Histological scoring revealed time and strain specific differences in perivascular recruitment of inflammatory cells in chronic and acute airway inflammation (P < 0·05). The data show that A/J strain is significantly more susceptible for perivascular inflammation followed by BALB/c and C57BL/6, while C3H/HeJ strain showed no perivascular accumulation of inflammatory cells. Of the two strains examined for perivascular inflammation in acute airway inflammation, BALB/c showed more accumulation of inflammatory cells compared to C57BL/c. VAP-1 expression occurred in the endothelium of pulmonary arteries but not in alveolar septa or airways in the control as well as challenged mice. In the inflamed lungs from A/J mice, the VAP-1 staining in pulmonary arteries was more intense compared to the other strains. VAP-1 staining was generally observed throughout the pulmonary arterial wall in chronic lung inflammation. These data show that periarterial inflammation is influenced by the genetic background, and may be partially regulated by VAP-1

Mortality after surgery in Europe: a 7 day cohort study

Background: Clinical outcomes after major surgery are poorly described at the national level. Evidence of heterogeneity between hospitals and health-care systems suggests potential to improve care for patients but this potential remains unconfirmed. The European Surgical Outcomes Study was an international study designed to assess outcomes after non-cardiac surgery in Europe.Methods: We did this 7 day cohort study between April 4 and April 11, 2011. We collected data describing consecutive patients aged 16 years and older undergoing inpatient non-cardiac surgery in 498 hospitals across 28 European nations. Patients were followed up for a maximum of 60 days. The primary endpoint was in-hospital mortality. Secondary outcome measures were duration of hospital stay and admission to critical care. We used χ² and Fisher’s exact tests to compare categorical variables and the t test or the Mann-Whitney U test to compare continuous variables. Significance was set at p&lt;0·05. We constructed multilevel logistic regression models to adjust for the differences in mortality rates between countries.Findings: We included 46 539 patients, of whom 1855 (4%) died before hospital discharge. 3599 (8%) patients were admitted to critical care after surgery with a median length of stay of 1·2 days (IQR 0·9–3·6). 1358 (73%) patients who died were not admitted to critical care at any stage after surgery. Crude mortality rates varied widely between countries (from 1·2% [95% CI 0·0–3·0] for Iceland to 21·5% [16·9–26·2] for Latvia). After adjustment for confounding variables, important differences remained between countries when compared with the UK, the country with the largest dataset (OR range from 0·44 [95% CI 0·19 1·05; p=0·06] for Finland to 6·92 [2·37–20·27; p=0·0004] for Poland).Interpretation: The mortality rate for patients undergoing inpatient non-cardiac surgery was higher than anticipated. Variations in mortality between countries suggest the need for national and international strategies to improve care for this group of patients.Funding: European Society of Intensive Care Medicine, European Society of Anaesthesiology