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A homodimeric fusion DNA vaccine targeting idiotype (Id) to antigen-presenting cells (APC) induced robust tumor protection in a mouse model of multiple myeloma (MM). Similar Id vaccine molecules were generated for four patients with MM with three main objectives: (i) do the vaccine molecules induce bona fide anti-Id immune responses in mice? (ii) does targeting of the vaccine molecules to APC enhance immune responses? (iii) can anti-Id antibodies, generated as by-product in vaccinated mice, be used to establish sensitive assays for complete remission (CR) prior to patient vaccination? Chimeric vaccine molecules targeting patient Id to mouse major histocompatibility complex (MHC) class II molecules were genetically constructed for four patients with MM. DNA vaccination of mice with chimeric vaccines targeting patient Id to mouse MHC class II molecules elicited antibodies specific for the patient's myeloma protein. Targeting MHC class II greatly enhanced anti-Id responses. Mouse anti-Id antibodies were used to establish myeloma protein-specific enzyme-linked immunosorbent assays (ELISAs) that were between 75 and 1500 times more sensitive than conventional serum protein electrophoresis and immunofixation. These results pave the way for testing targeted DNA Id vaccines in patients in CR. Id- and patient-specific ELISA could be established affording evaluation of CR depth beyond current serological methods. [ABSTRACT FROM AUTHOR]

Abstract: Efficacy of DNA vaccination has been improved in mice by fusion vaccines targeting antigen to antigen-presenting cells (APC) via chemokine receptors. Here, we aimed at extending this strategy to large animals and humans. Fusion proteins equipped with human MIP1α (LD78β isoform) retained functional activity and conformational correctness of targeting and antigenic units, respectively. Fusion proteins improved responses of cloned human CD4+ T cells, and a two amino acid NH2-truncated version of LD78β outperformed full length LD78β-vaccine proteins in vitro. LD78β DNA fusion vaccines induced improved T cell (both CD4+ and CD8+) and antibody responses in mice following plasmid injection and skin electroporation. Finally, LD78β-vaccine proteins bound Rhesus macaque CCR5, setting the stage for targeted DNA immunization in non-human primates. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the clinical significance of tumour-infiltrating FOXP3-positive regulatory T cells (Tregs) in radically resected (R0) gastric cancer. From a single-institution database, tumors of 110 patients who underwent R0 resection for stage II–III disease were studied for FOXP3-positive Tregs by immunohistochemistry. The observed median number of FOXP3-positive Tregs was used as the cut-point in analyses (<6 versus ⩾6 count). Tregs were significantly higher in gastric carcinomas than in normal tissue (P =0.0001). Tregs count ⩾6 was significantly associated with vascular/lymphatic/perineural invasion (VELIPI) in the tumour (P =0.03). Multivariate analysis showed association between adverse relapse-free survival and grading 3, stage III, VELIPI and Tregs count ⩾6 (P =0.02). Adverse overall survival was associated with grading 3, stage III, VELIPI and Tregs count ⩾6 (P =0.006). FOXP3-positive Tregs may be a novel marker for identifying high-risk gastric cancer patients. Present findings deserve additional investigation as Tregs may also represent an innovative therapeutic target. [Copyright &y& Elsevier]

β-Defensins are small antimicrobial peptides of the innate immune system produced in response to microbial infection of mucosal tissue and skin. We demonstrate that murine β-defensin 2 (mDF2β) acts directly on immature dendritic cells as an endogenous ligand for Toll-like receptor 4 (TLR-4), inducing up-regulation of costimulatory molecules and dendritic cell maturation. These events, in turn, trigger robust, type 1 polarized adaptive immune responses in vivo, suggesting that mDF2β may play an important role in immunosurveillance against pathogens and, possibly, self antigens or tumor antigens. [ABSTRACT FROM AUTHOR]

Background: Therapeutic idiotypic (Id) vaccination is an experimental treatment for selected B cell malignancies. A broader use of Id-based vaccination, however, is hampered by the complexity and costs due to the individualized production of protein vaccines. These limitations may be overcome by targeted DNA vaccines encoding stereotyped immunoglobulin V regions of B cell malignancies. We have here investigated whether such vaccines might elicit cross-reactive immune responses thus offering the possibility to immunize subsets of patients with the same vaccine.Methods: Fusion vaccines targeting patient Id to mouse Major Histocompatibility Complex (MHC) class II molecules (chimeric mouse/human) or chemokine receptors (fully human) on antigen-presenting cells (APC) were genetically constructed for two Chronic Lymphocytic Leukemia (CLL) patients and one prototypic stereotyped B-cell receptor (BCR) commonly expressed by Hepatitis C Virus (HCV)-associated Non Hodgkin Lymphoma (NHL). The A20 murine B lymphoma cells were engineered to express prototypic HCV-associated B cell lymphoma BCR. Anti-Id antibody responses were studied against stereotyped and non-stereotyped BCRs on CLL patients' cells as well as transfected A20 cells.Results: DNA vaccination of mice with Id vaccines that target APC elicited increased amounts of antibodies specific for the patient's Id as compared with non targeted control vaccines. Anti-Id antibodies cross-reacted between CLL cells with closely related BCR. A20 cells engineered to express patients' V regions were not tumorigenic in mice, preventing tumor challenge experiments.Conclusions: These findings provide experimental support for use of APC-targeted fusion Id DNA vaccines for the treatment of B cell lymphoma and CLL that express stereotyped BCRs. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the ability of ladarixin (LDX, 400 mg twice‐daily for three cycles of 14 days on/14 days off), an inhibitor of the CXCR1/2 chemokine receptors, to maintain C‐peptide production in adult patients with newly diagnosed type 1 diabetes. Materials and Methods: A double‐blind, randomized (2:1), placebo‐controlled study was conducted in 45 males and 31 females (aged 18‐46 years) within 100 days of the first insulin administration. The primary endpoint was the area under the curve (AUC) for C‐peptide in response to a 2‐hour mixed meal tolerance test (AUC[0‐120 min]) at week 13 ± 1. Secondary endpoints included C‐peptide AUC(15‐120 min), HbA1c, daily insulin requirement, severe hypoglycaemic events (SHE), the proportion of subjects achieving HbA1c less than 7.0% without SHE and maintaining a residual beta cell function. Follow‐up assessments were scheduled at weeks 13 ± 1, 26 ± 2 and 52 ± 2. Results: In total, 26/26 (100%, placebo) and 49/50 (98%, LDX) patients completed week 13. The mean change from baseline to week 13 in C‐peptide AUC(0‐120 min) was −0.144 ± 0.449 nmol/L with placebo and 0.003 ±.322 nmol/L with LDX. The difference was not significant (0.149 nmol/L, 95% CI −0.04 to 0.33; P =.122). At week 26, the proportion of patients with HbA1c less than 7.0% without SHE was transiently higher in the LDX group (81% vs. 54%, P =.024). Otherwise, no significant secondary endpoint differences were noted. Transient metabolic benefit was seen at week 26 in favour of the LDX group in the prespecified subpopulation with fasting C‐peptide less than the median value at screening. Conclusions: In newly diagnosed patients with type 1 diabetes, short‐term LDX treatment had no appreciable effect on preserving residual beta cell function. [ABSTRACT FROM AUTHOR]

Abstract: Active immunization of follicular lymphoma patients with idiotypic vaccines elicits antigen-specific antibody responses, T-cell responses, and antitumor effects. We hypothesized that these vaccinated patients could generate tumor-specific immune responses, not only against idiotype, but also against other tumor-associated antigens (TAA) by a mechanism of epitope spreading. To identify potential antigens, a phage surface expressed cDNA library derived from primary tumor cells was screened with sera from idiotype-vaccinated patients. Consistent with our hypothesis, we identified two immunogenic peptides (FL-aa-7 and 18), unrelated to idiotype, which were recognized by postvaccine sera but not by prevaccine or normal human sera. These peptide sequences derived from the 5′-untranslated regions of the human GTPase, IMAP family member 7 gene (FL-aa-7) and an alternative reading frame of U1-snRNP 70 (FL-aa-18), respectively, suggesting that epitope spreading had occurred. [Copyright &y& Elsevier]

Objective: Reparixin is an inhibitor of CXCR1/2 chemokine receptor shown to be an effective anti-inflammatory adjuvant in a pilot clinical trial in allotransplant recipients.Research Design and Methods: A phase 3, multicenter, randomized, double-blind, parallel-assignment study (NCT01817959) was conducted in recipients of islet allotransplants randomized (2:1) to reparixin or placebo in addition to immunosuppression. Primary outcome was the area under the curve (AUC) for C-peptide during the mixed-meal tolerance test at day 75 ± 5 after the first and day 365 ± 14 after the last transplant. Secondary end points included insulin independence and standard measures of glycemic control.Results: The intention-to-treat analysis did not show a significant difference in C-peptide AUC at both day 75 (27 on reparixin vs. 18 on placebo, P = 0.99) and day 365 (24 on reparixin vs. 15 on placebo, P = 0.71). There was no statistically significant difference between treatment groups at any time point for any secondary variable. Analysis of patient subsets showed a trend for a higher percentage of subjects retaining insulin independence for 1 year after a single islet infusion in patients receiving reparixin as compared with patients receiving placebo (26.7% vs. 0%, P = 0.09) when antithymocyte globulin was used as induction immunosuppression.Conclusions: In this first double-blind randomized trial, islet transplantation data obtained with reparixin do not support a role of CXCR1/2 inhibition in preventing islet inflammation-mediated damage. [ABSTRACT FROM AUTHOR]

Chemokines and their receptors have been associated with or implicated in the pathogenesis of type 1 diabetes (T1D), but the identification of a single specific chemokine/receptor pathway that may constitute a suitable target for the development of therapeutic interventions is still lacking. Here, we used multiple low-dose (MLD) streptozotocin (STZ) injections and the NOD mouse model to investigate the potency of CXCR1/2 inhibition to prevent inflammation- and autoimmunity-mediated damage of pancreatic islets. Reparixin and ladarixin, noncompetitive allosteric inhibitors, were used to pharmacologically blockade CXCR1/2. Transient blockade of said receptors was effective in preventing inflammation-mediated damage in MLD-STZ and in preventing and reversing diabetes in NOD mice. Blockade of CXCR1/2 was associated with inhibition of insulitis and modification of leukocytes distribution in blood, spleen, bone marrow, and lymph nodes. Among leukocytes, CXCR2+ myeloid cells were the most decreased subpopulations. Together these results identify CXCR1/2 chemokine receptors as "master regulators" of diabetes pathogenesis. The demonstration that this strategy may be successful in preserving residual b-cells holds the potential to make a significant change in the approach to management of human T1D. [ABSTRACT FROM AUTHOR]

Although long considered a promising treatment option for type 1 diabetes, pancreatic islet cell transformation has been hindered by immune system rejection of engrafted tissue. The identification of pathways that regulate post-transplant detrimental inflammatory events would improve management and outcome of transplanted patients. Here, we found that CXCR1/2 chemokine receptors and their ligands are crucial negative determinants for islet survival after transplantation. Pancreatic islets released abundant CXCR1/2 ligands (CXCL1 and CXCL8). Accordingly, intrahepatic CXCL1 and circulating CXCL1 and CXCL8 were strongly induced shortly after islet infusion. Genetic and pharmacological blockade of the CXCL1-CXCR1/2 axis in mice improved intrahepatic islet engraftment and reduced intrahepatic recruitment of polymorphonuclear leukocytes and NKT cells after islet infusion. In humans, the CXCR1/2 allosteric inhibitor reparixin improved outcome in a phase 2 randomized, open-label pilot study with a single infusion of allogeneic islets. These findings indicate that the CXCR1/2-mediated pathway is a regulator of islet damage and should be a target for intervention to improve the efficacy of transplantation. [ABSTRACT FROM AUTHOR]

Nucleoside transporter proteins are specialized proteins that mediate the transport of nucleosides and nucleoside analog drugs across the plasma membrane. The human equilibrative nucleoside transporter 1 (hENT1) is a member of these proteins and mediates cellular entry of gemcitabine, cytarabine, and fludarabine. The hENT1 expression has been demonstrated to be related with prognosis and activity of gemcitabine-based therapy in breast, ampullary, lung, and pancreatic cancer. We investigated the immunohistochemical expression of hENT in tumor samples from 111 patients with resected gastric adenocarcinoma, correlating these data with clinical parameters and disease outcomes. None of the patients received chemotherapy or radiation therapy before or after surgery as a part of an adjuvant or neoadjuvant program. On univariate survival analysis, the hENT1 expression was associated with overall survival (OS) and disease free survival (DFS). Specifically, those patients with overexpression of hENT1 showed a shorter OS (P = 0.021) and a shorter DFS (P = 0.033). Considering only the node positive patients, higher hENT levels were associated with significantly shorter median DFS (21.7 months; 95% CI 11.1–32.4) compared with patients with low expression of hENT1. The hENT1 expression was defined, in the lymph-node positive patients, as an independent prognostic factor (P = 0.019). Furthermore, considering only patients with diffuse or mixed tumors and lymph-node positive, the expression of hENT1 was strongly related with DFS and OS. Immunohistochemistry for the hENT1 protein carries prognostic information in patients with resected gastric cancer and holds promise as a predictive factor in chemotherapy decisions. J. Cell. Physiol. 223: 384–388, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]