47 research outputs found

    Co-Administration of IL-1+IL-6+TNF-α with Mycobacterium tuberculosis Infected Macrophages Vaccine Induces Better Protective T Cell Memory than BCG

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    BCG has been administered globally for more than 75 years, yet tuberculosis (TB) continues to kill more than 2 million people annually. Further, BCG protects childhood TB but is quite inefficient in adults. This indicates that BCG fails to induce long-term protection. Hence there is a need to explore alternative vaccination strategies that can stimulate enduring T cell memory response. Dendritic cell based vaccination has attained extensive popularity following their success in various malignancies. In our previous study, we have established a novel and unique vaccination strategy against Mycobacterium tuberculosis (M. tb) and Salmonella typhimurium by utilizing infected macrophages (IM). In short-term experiments (30 days), substantial degree of protection was observed. However, remarkable difference was not observed in long-term studies (240 days) due to failure of the vaccine to generate long-lasting memory T cells. Hence, in the present study we employed T cell memory augmenting cytokines IL-1+IL-6+TNF-α and IL-7+IL-15 for the induction of the enhancement of long-term protection by the vaccine. We co-administered the M. tb infected macrophages vaccine with IL-1+IL-6+TNF-α (IM-1.6.α) and IL-7+IL-15 (IM-7.15). The mice were then rested for a reasonably large period (240 days) to study the bona fide T cell memory response before exposing them to aerosolized M. tb. IM-1.6.α but not IM-7.15 significantly improved memory T cell response against M. tb, as evidenced by recall responses of memory T cells, expansion of both central as well as effector memory CD4 and CD8 T cell pools, elicitation of mainly Th1 memory response, reduction in the mycobacterial load and alleviated lung pathology. Importantly, the protection induced by IM-1.6.α was significantly better than BCG. Thus, this study demonstrates that not only antigen-pulsed DCs can be successfully employed as vaccines against cancer and infectious diseases but also macrophages infected with M. tb can be utilized with great efficacy especially in protection against TB

    Diclofenac Inhibits Tumor Growth in a Murine Model of Pancreatic Cancer by Modulation of VEGF Levels and Arginase Activity

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    BACKGROUND: Diclofenac is one of the oldest anti-inflammatory drugs in use. In addition to its inhibition of cyclooxygenases (COX), diclofenac potently inhibits phospholipase A(2) (PLA(2)), thus yielding a broad anti-inflammatory effect. Since inflammation is an important factor in the development of pancreatic tumors we explored the potential of diclofenac to inhibit tumor growth in mice inoculated with PANCO2 cells orthotopically. METHODOLOGY/PRINCIPAL FINDINGS: We found that diclofenac treatment (30 mg/kg/bw for 11 days) of mice inoculated with PANC02 cells, reduced the tumor weight by 60%, correlating with increased apoptosis of tumor cells. Since this effect was not observed in vitro on cultured PANCO2 cells, we theorized that diclofenac beneficial treatment involved other mediators present in vivo. Indeed, diclofenac drastically decreased tumor vascularization by downregulating VEGF in the tumor and in abdominal cavity fluid. Furthermore, diclofenac directly inhibited vascular sprouting ex vivo. Surprisingly, in contrast to other COX-2 inhibitors, diclofenac increased arginase activity/arginase 1 protein content in tumor stroma cells, peritoneal macrophages and white blood cells by 2.4, 4.8 and 2 fold, respectively. We propose that the subsequent arginine depletion and decrease in NO levels, both in serum and peritoneal cavity, adds to tumor growth inhibition by malnourishment and poor vasculature development. CONCLUSION/SIGNIFICANCE: In conclusion, diclofenac shows pronounced antitumoral properties in pancreatic cancer model that can contribute to further treatment development. The ability of diclofenac to induce arginase activity in tumor stroma, peritoneal macrophages and white blood cells provides a tool to study a controversial issue of pro-and antitumoral effects of arginine depletion

    RTA Promoter Demethylation and Histone Acetylation Regulation of Murine Gammaherpesvirus 68 Reactivation

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    Gammaherpesviruses have a common biological characteristic, latency and lytic replication. The balance between these two phases in murine gammaherpesvirus 68 (MHV-68) is controlled by the replication and transcription activator (RTA) gene. In this report, we investigated the effect of DNA demethylation and histone acetylation on MHV-68 replication. We showed that distinctive methylation patterns were associated with MHV-68 at the RTA promoter during latency or lytic replication. Treatment of MHV-68 latently-infected S11E cells with a DNA methyltransferases (DNMTs) inhibitor 5-azacytidine (5-AzaC), only weakly reactivated MHV-68, despite resulted in demethylation of the viral RTA promoter. In contrast, treatment with a histone deacetylase (HDAC) inhibitor trichostatin A (TSA) strongly reactivated MHV-68 from latency, and this was associated with significant change in histone H3 and H4 acetylation levels at the RTA promoter. We further showed that HDAC3 was recruited to the RTA promoter and inhibited RTA transcription during viral latency. However, TSA treatment caused rapid removal of HDAC3 and also induced passive demethylation at the RTA promoter. In vivo, we found that the RTA promoter was hypomethylated during lytic infection in the lung and that methylation level increased with virus latent infection in the spleen. Collectively, our data showed that histone acetylation, but not DNA demethylation, is sufficient for effective reactivation of MHV-68 from latency in S11E cells

    Th17 cytokines and arthritis

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    Th17 cells are implicated in human autoimmune diseases, such as rheumatoid arthritis (RA), although it has not been established whether this persistent destructive arthritis is driven by Th1 and/or Th17 cells. Interleukin-17A (IL-17A) contributes to the pathogenesis of arthritis as has been shown in several experimental arthritis models. Importantly, recent data from first clinical trials with anti-IL-17A antibody treatment in psoriatic arthritis patients and RA patients looks promising. This review summarizes the findings about the role of Th17 cells in arthritis and discusses the impact of the different Th17 cytokines in the pathogenesis of this disease. However, further studies are needed to unravel the interplay between IL-17A and other Th17 cytokines such as IL-17F, IL-22, and IL-21 in the pathoimmunological process of this crippling disease, in particular, whether regulating Th17 cell activity or specific combinations of Th17 cytokines will have additional value compared to neutralizing IL-17A activity alone. Moreover, tumor necrosis factor-positive Th17 cells are discussed as potential dangerous cells in driving persistent arthritis in human early RA

    Selective Internal Radiation Therapy with SIR-Spheres for the Treatment of Unresectable Colorectal Hepatic Metastases

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    The purpose of this study was to evaluate the effectiveness of colorectal cancer (CRC) liver metastasis radioembolization with yttrium-90 (Y90), assessing toxicity and survival rates in patients with no response to chemotherapy through our 3-year experience. From February 2005 to January 2008, we treated 41 patients affected by CRC from a cohort of selective internal radiation therapy patients treated at our institution. All patients examined showed disease progression and arrived for our observation with an abdominal CT, a body PET, and a hepatic angiography followed by gastroduodenal artery coiling previously performed by us. We excluded patients with a bilirubin level > 1.8 mg/dl and pulmonary shunt > 20% but not patients with minor extrahepatic metastases. On treatment day, under fluoroscopic guidance, we implanted a dose of Y90 microspheres calculated on the basis of liver tumoral involvement and the body surface area formula. All patients were discharged the day after treatment. We obtained, according to Response Evaluation Criteria on Solid Tumors, a complete response in 2 patients, a partial response in 17 patients, stable disease in 14 patients, and progressive disease in 8 patients. In all cases, we obtained a carcinoembryonic antigen level decrease, especially in the week 8 evaluation. Technical success rate was 98% and technical effectiveness estimated at 3 months after treatment was 80.5%. Side effects graded by Common Terminology Criteria on Adverse Events were represented by one grade 4 hepatic failure, two grade 2 gastritis, and one grade 2 cholecystitis. The median survival and the progression-free survival calculated by Kaplan-Meier analysis were 354 and 279 days, respectively. In conclusion, according to our 3-year experience, Y90 SIR-Spheres radioembolization is a feasible and safe method to treat CRC liver metastases, with an acceptable level of complications and a good response rate
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