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Refereed/Peer-reviewed Visceral adipose tissue (VAT) encases mesenteric lymphatic vessels and lymph nodes through which lymph is transported from the intestine and mesentery. Whether mesenteric lymphatics contribute to adipose tissue inflammation and metabolism and insulin resistance is unclear. Here we show that obesity is associated with profound and progressive dysfunction of the mesenteric lymphatic system in mice and humans. We find that lymph from mice and humans consuming a high-fat diet (HFD) stimulates lymphatic vessel growth, leading to the formation of highly branched mesenteric lymphatic vessels that ‘leak’ HFD-lymph into VAT and, thereby, promote insulin resistance. Mesenteric lymphatic dysfunction is regulated by cyclooxygenase (COX)-2 and vascular endothelial growth factor (VEGF)-C–VEGF receptor (R)3 signalling. Lymph-targeted inhibition of COX-2 using a glyceride prodrug approach reverses mesenteric lymphatic dysfunction, visceral obesity and inflammation and restores glycaemic control in mice. Targeting obesity-associated mesenteric lymphatic dysfunction thus represents a potential therapeutic option to treat metabolic disease.

Symbiodiniaceae algae are often photosymbionts of reef-building corals. The establishment of their symbiosis resembles a microbial infection where eukaryotic pattern recognition receptors (e.g. lectins) are thought to recognize a specific range of taxon-specific microbial-associated molecular patterns (e.g. glycans). The present study used the sea anemone, Exaiptasia diaphana and three species of Symbiodiniaceae (the homologous Breviolum minutum, the heterologous-compatible Cladocopium goreaui and the heterologous-incompatible Fugacium kawagutii) to compare the surface glycomes of three symbionts and explore the role of glycan–lectin interactions in host–symbiont recognition and establishment of symbiosis. We identified the nucleotide sugars of the algal cells, then examined glycans on the cell wall of the three symbiont species with monosaccharide analysis, lectin array technology and fluorescence microscopy of the algal cell decorated with fluorescently tagged lectins. Armed with this inventory of possible glycan moieties, we then assayed the ability of the three Symbiodiniaceae to colonize aposymbiotic E. diaphana after modifying the surface of one of the two partners. The Symbiodiniaceae cell-surface glycome varies among algal species. Trypsin treatment of the alga changed the rate of B. minutum and C. goreaui uptake, suggesting that a protein-based moiety is an essential part of compatible symbiont recognition. Our data strongly support the importance of D-galactose (in particular β-D-galactose) residues in the establishment of the cnidarian–dinoflagellate symbiosis, and we propose a potential involvement of L-fucose, D-xylose and D-galacturonic acid in the early steps of this mutualism.

Visceral adipose tissue (VAT) encases mesenteric lymphatic vessels and lymph nodes through which lymph is transported from the intestine and mesentery. Whether mesenteric lymphatics contribute to adipose tissue inflammation and metabolism and insulin resistance is unclear. Here we show that obesity is associated with profound and progressive dysfunction of the mesenteric lymphatic system in mice and humans. We find that lymph from mice and humans consuming a high-fat diet (HFD) stimulates lymphatic vessel growth, leading to the formation of highly branched mesenteric lymphatic vessels that 'leak' HFD-lymph into VAT and, thereby, promote insulin resistance. Mesenteric lymphatic dysfunction is regulated by cyclooxygenase (COX)-2 and vascular endothelial growth factor (VEGF)-C-VEGF receptor (R)3 signalling. Lymph-targeted inhibition of COX-2 using a glyceride prodrug approach reverses mesenteric lymphatic dysfunction, visceral obesity and inflammation and restores glycaemic control in mice. Targeting obesity-associated mesenteric lymphatic dysfunction thus represents a potential therapeutic option to treat metabolic disease.

Immunization with autologous dendritic cells (DCs) loaded with a heat shock-conditioned allogeneic melanoma cell lysate caused lysate-specific delayed type hypersensitivity (DTH) reactions in a number of patients. These responses correlated with a threefold prolonged long-term survival of DTH(+) with respect to DTH(-) unresponsive patients. Herein, we investigated whether the immunological reactions associated with prolonged survival were related to dissimilar cellular and cytokine responses in blood.Healthy donors and melanoma patient's lymphocytes obtained from blood before and after vaccinations and from DTH biopsies were analyzed for T cell population distribution and cytokine release.Peripheral blood lymphocytes from melanoma patients have an increased proportion of Th3 (CD4(+) TGF-β(+)) regulatory T lymphocytes compared with healthy donors. Notably, DTH(+) patients showed a threefold reduction of Th3 cells compared with DTH(-) patients after DCs vaccine treatment. Furthermore, DCs vaccination resulted in a threefold augment of the proportion of IFN-γ releasing Th1 cells and in a twofold increase of the IL-17-producing Th17 population in DTH(+) with respect to DTH(-) patients. Increased Th1 and Th17 cell populations in both blood and DTH-derived tissues suggest that these profiles may be related to a more effective anti-melanoma response.Our results indicate that increased proinflammatory cytokine profiles are related to detectable immunological responses in vivo (DTH) and to prolonged patient survival. Our study contributes to the understanding of immunological responses produced by DCs vaccines and to the identification of follow-up markers for patient outcome that may allow a closer individual monitoring of patients.

Adoptive T cell therapy (ACT) with antitumor CTL is a promising and tailored treatment against cancer. We investigated the role played by the affinity and avidity of the interaction between the tumor and the CTL on the outcome of ACT against a mouse non-Hodgkin B cell lymphoma that expresses OVA as a model neoantigen. ACT was assessed under conditions where antitumor CTL expressed TCR of varying affinity for OVA. We also assessed conditions where the avidity of Ag recognition varied because the lymphoma cells expressed high or low levels of OVA. Efficient eradication of small tumor burdens was achieved by high- or low-affinity CTL. Tumors expressing low levels of OVA could also be eliminated. However, ACT against large tumor burdens was unsuccessful, accompanied by CTL deletion and functional impairment. This negative outcome was not prevented by lowering the affinity of the CTL or the expression of OVA in the lymphoma. Thus, tumor burden, rather than CTL affinity or avidity, appears to be the main determinant of ACT outcomes in our lymphoma model. Insofar as our results can be extrapolated to the clinical setting, they imply that the range of CTL and tumor-associated Ag combinations that may be effectively harnessed in ACT against lymphoma may be wider than generally assumed. CTL expressing low-affinity TCR may be effective against lymphoma, and lowly expressed tumor-associated Ag should be considered as potential targets, but tumor reduction should always be implemented before infusion of the CTL.

In this study, the authors examined the characteristics of family-generated videotapes used to manage the manifestation of verbally disruptive behaviors (VDB) in nursing home residents. Videotapes prepared by the relatives of 30 verbally disruptive nursing home residents to be shown to residents were systematically observed and coded for content and mode of presentation. The relationship between the videotapes' characteristics and their impact on the resident was studied. The majority of the time in the videotape was spent talking about the past or present of the family, was characterized by an overall feeling of respect, and did not show great variability in the features examined. Videotapes coded as showing more love and those not talking about current events were associated with higher effectiveness in reducing VDB. This treatment proved to be an appropriate and rewarding avenue to involve family members in the care of their frail institutionalized elderly relatives.

We have previously demonstrated that IT9302, a nonameric peptide homologous to the C-terminal domain of human IL-10, mimics several effects of the cytokine including down-regulation of the antigen presentation machinery and increased sensitivity of tumor cells to NK-mediated lysis. In the present report, we have explored a potential therapeutic utility for IT9302 related to the ex vivo production of tolerogenic dendritic cells (DCs). Our results indicate that IT9302 impedes human monocyte response to differentiation factors and reduces antigen presentation and co-stimulatory capacity by DCs. Additionally, peptide-treated DCs show impaired capacity to stimulate T-cell proliferation and IFN-gamma production. IT9302 exerts its effect through mechanisms, in part, distinct from IL-10, involving STAT3 inactivation and NF-kappa B intracellular pathway. IT9302-treated DCs display increased expression of membrane-associated TGF-beta, linked to a more effective induction of foxp3+ regulatory T cells. These results illustrate for the first time that a short synthetic peptide can promote monocytes differentiation to tolerogenic DCs with therapeutic potential for the treatment of autoimmune and transplantation-related immunopathologic disease. (c) 2011 Elsevier GmbH. All rights reserved.

Purpose The aim of this work was to assess immunologic response, disease progression, and post-treatment survival of melanoma patients vaccinated with autologous dendritic cells (DCs) pulsed with a novel allogeneic cell lysate (TRIMEL) derived from three melanoma cell lines. Patients and Methods Forty-three stage IV and seven stage III patients were vaccinated four times with TRIMEL/DC vaccine. Specific delayed type IV hypersensitivity (DTH) reaction, ex vivo cytokine production, and regulatory T-cell populations were determined. Overall survival and disease progression rates were analyzed using Kaplan-Meier curves and compared with historical records. Results The overall survival for stage IV patients was 15 months. More than 60% of patients showed DTH-positive reaction against the TRIMEL. Stage IV/DTH-positive patients displayed a median survival of 33 months compared with 11 months observed for DTH-negative patients (P = .0014). All stage III treated patients were DTH positive and remained alive and tumor free for a median follow-up period of 48 months (range, 33 to 64 months). DTH-positive patients showed a marked reduction in the proportion of CD4+ transforming growth factor (TGF) β+ regulatory T cells compared to DTH-negative patients (1.54% v 5.78%; P < .0001). Conclusion Our findings strongly suggest that TRIMEL-pulsed DCs provide a standardized and widely applicable source of melanoma antigens, very effective in evoking antimelanoma immune response. To our knowledge, this is the first report describing a correlation between vaccine-induced reduction of CD4+TGFβ+ regulatory T cells and in vivo antimelanoma immune response associated to improved patient survival and disease stability.

The ability of DCs to induce a primary immune response makes them ideal candidates for cancer vaccines against tumors. Recently, in a serie of phase I/II clinical studies, we showed the effectiveness of autologous DCs loaded with a conditioned allogeneic melanoma cell lysate named TRIMEL. Our results demonstrated a correlation between positive tumor-specific delayed type hypersensitivity (DTH) reaction induced by DC-vaccination, and improved long-term patient survival in late-stage melanoma patients. In fact, 60% of patients showed a positive DTH reaction showing a three-fold prolonged survival compared to non-responder patients (33 and 11 months respectively). Herein, we investigated whether cellular and cytokine profiles in patients PBL before and after vaccination reflects differential responses associated to the clinical outcome. Analysis of T cell populations in blood showed that melanoma patients (n=28) have an increased proportion of Th3 (CD4+TGF-β+) regulatory T lymphocytes (2.64 % ± 0.16) compared to normal donors (n=14) (1.72 % ± 0.22). However, we didn't observed differences in TGF-β concentrations at serum level. Moreover, we analyzed vaccine effect on cytokine and cellular responses in PBL. Interestling, although there was not differences in Th3 population proportions between responder (n=14) and non-responder patients (n=14) before vaccination, after treatment responder patients showed a three-fold reduction of CD4+TGf-β+ T cells compared to non-responders (1.65 % ± 0.19 and 5.54 % ± 0.28 respectively). Furthermore, our results show that DC-vaccination resulted in a three-fold augment of IFN-γ releasing by Th1 population and a two-fold increase of IL-17 producing Th17 lymphocyte population in responder patients, but not in non-responders. A direct correlation between IFN-γ and IL-17 production in responder patients blood was observed (p < 0.0001) suggesting that those cytokines may favour an anti melanoma response. Taken together our results indicates that despite undetectable differences in the cellular and cytokine profiles in melanoma patients before DC-vaccination, immunization resulted in two different pattern of response associated to the immunological and clinical outcome. Our study may contribute to a better understanding of clinical immunological responses and to an earlier prognosis of patient outcome. Citation Information: Clin Cancer Res 2010;16(7 Suppl):B18