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The objective of modern vaccine development is the safe generation of protective long-term immune memory, both prophylactic and therapeutic. Live attenuated vaccines generate potent cellular and humoral immunity 0005, 0010 and 0015, but numerous problems exist with these vaccines, ranging from production and storage issues to adverse reactions and reversion to virulence. Subunit vaccines are safer, more stable, and more amenable to mass production. However the protection they produce is frequently inferior to live attenuated vaccines and is typically confined to humoral, and not cellular immunity. Unfortunately, there are presently no subunit vaccines available clinically that are effective at eliciting cellular responses let alone cellular memory [4]. This article will provide and overview of areas of investigation that we see as important for the development of vaccines with the capacity to induce robust and enduring cellular immune responses.  相似文献   
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Population-based surveys have long been a key tool for health researchers, policy makers and program managers. The addition of bio-measures, including physical measures and specimen collection, to self-reported health and health behaviors can increase the value of the research for health sciences. At the same time, these bio-measures are likely to increase the perceived burden and intrusiveness to the respondent. Relatively little research has been reported on respondent willingness to participate in surveys that involve physical measures and specimen collection and whether there is any associated non-response bias.This paper explores the willingness of respondents to participate in surveys that involve physical measures and biomarkers. A Census-balanced sample of nearly 2000 adults from a national mobile panel of persons residing in the U.S. were interviewed. Willingness to participate in six specific bio-measures was assessed. The survey finds a high correlation in the willingness of respondents to participate among these specific bio-measures. This suggests there is a general propensity towards (and against) bio-measures among potential respondents, despite some differences in willingness to participate in the more sensitive, intrusive or burdensome biomarkers. This study finds the general propensity to participate in bio-measures is correlated with a number of key measures of health and illness. This suggests that the inclusion of biomarkers in health surveys may introduce some bias in key measures that need to be balanced against the value of the additional information.  相似文献   
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Group A Streptococcus (GAS) is a human pathogen causing a wide range of mild to severe and life-threatening diseases. The GAS M1 protein is a major virulence factor promoting GAS invasiveness and resistance to host innate immune clearance. M1 displays an irregular coiled-coil structure, including the B-repeats that bind fibrinogen. Previously, we found that B-repeat stabilisation generates an idealised version of M1 (M1*) characterised by decreased fibrinogen binding in vitro. To extend these findings based on a soluble truncated version of M1, we now studied the importance of the B-repeat coiled-coil irregularities in full length M1 and M1* expressed in live GAS and tested whether the modulation of M1–fibrinogen interactions would open up novel therapeutic approaches. We found that altering either the M1 structure on the GAS cell surface or removing its target host protein fibrinogen blunted GAS virulence. GAS expressing M1* showed an impaired ability to adhere to and to invade human endothelial cells, was more readily killed by whole blood or neutrophils and most importantly was less virulent in a murine necrotising fasciitis model. M1-mediated virulence of wild-type GAS was strictly dependent on the presence and concentration of fibrinogen complementing our finding that M1–fibrinogen interactions are crucial for GAS virulence. Consistently blocking M1–fibrinogen interactions by fragment D reduced GAS virulence in vitro and in vivo. This supports our conclusion that M1–fibrinogen interactions are crucial for GAS virulence and that interference may open up novel complementary treatment options for GAS infections caused by the leading invasive GAS strain M1.  相似文献   
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Avelumab (Bavencio®) is a fully human IgG1 monoclonal antibody that is directed against programmed cell death ligand 1 (PD-L1). Avelumab functions as an immune checkpoint inhibitor and has recently been approved in the USA, the EU and Japan for the treatment of metastatic Merkel cell carcinoma (MCC). It is thus the first therapeutic agent specifically approved for use in this indication, and is approved for use independent of line of treatment. Approval for avelumab in metastatic MCC was based on the two-part, single-arm, phase II trial, JAVELIN Merkel 200. In Part A of the study, confirmed objective responses were observed in approximately one-third of patients with chemotherapy-refractory metastatic MCC treated with avelumab. The responses were observed early and appeared to be durable, with an estimated 74% of responses having a duration ≥?12 months. Furthermore, interim results from a separate cohort of patients (Part B) indicate an objective response rate for avelumab of >?60% in patients who were chemotherapy-naïve in the metastatic disease setting. Avelumab is associated with a risk of immune-related adverse events but, overall, has an acceptable and manageable safety and tolerability profile. In conclusion, currently available data suggest that avelumab presents a clinically beneficial new treatment option for metastatic MCC, a rare but aggressive cancer associated with a poor prognosis.  相似文献   
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