Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity. In naïve mice, both Ad26.RSV.preF and preF protein induced humoral responses, whereas cellular responses were only elicited by Ad26.RSV.preF. In RSV pre-exposed mice, a single dose of either vaccine induced cellular responses and strong humoral responses. Ad26-induced RSV-specific cellular immune responses were detected systemically and locally in the lungs. Both vaccines showed protective efficacy in the cotton rat model, but Ad26.RSV.preF conferred protection at lower virus neutralizing titers in comparison to RSV preF protein. Factors that may contribute to the protective capacity of Ad26.RSV.preF elicited immunity are the induced IgG2a antibodies that are able to engage Fcγ receptors mediating Antibody Dependent Cellular Cytotoxicity (ADCC), and the induction of systemic and lung resident RSV specific CD8 + T cells. These data demonstrate qualitative improvement of immune responses elicited by an adenoviral vector based vaccine encoding the RSV preF antigen compared to the subunit vaccine in small animal models which may inform RSV vaccine development. 相似文献
Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC. 相似文献
1. Allyl methyl disulfide (AMDS) is one of the main compounds in garlic, whereas its metabolism has not been studied yet.
2. In this work, we first identified the metabolites of AMDS in rat erythrocytes and rats using GC–MS. The transformation mechanism study among different metabolites was then conducted. The apparent kinetics of AMDS in rat erythrocytes and pharmacokinetics of AMDS by oral administration in rats were also studied.
3. The metabolic pathway study showed that AMDS was mainly metabolized in rats to allyl methyl sulfoxide (AMSO) and allyl methyl sulfone (AMSO2) through mechanisms of reduction, methylation and oxidation. The transformation mechanism study indicated that AMDS was firstly reduced to allyl mercaptan (AM) in rat erythrocytes, and then methylated to allyl methyl sulfide (AMS) by S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH), and finally oxidized to AMSO and AMSO2 by liver microsomes. The half-life of AMDS in rat erythrocytes was 6.285?±?0.014?min while the half-lives of its active metabolites AMSO and AMSO2in vivo were 18.17 and 17.50?h, respectively. Also, the large AUCs of the two active metabolites were observed, indicating potential applications of AMDS for certain pharmacological effects. 相似文献