Background: Although ferret antisera used in influenza surveillance did not detect antigenic drift of A(H1N1)pdm09 viruses during the 2015-2016 season, low vaccine effectiveness was reported in adults. We investigated the immune basis of low responses to circulating A(H1N1)pdm09 viruses after vaccination.
Methods: Prevaccination and postvaccination serum samples collected from >300 adults (aged 18-49 years) in 6 seasons (2010-2011 to 2015-2016) were analyzed using hemagglutination inhibition assays to evaluate the antibody responses to 13 A(H1N1) viruses circulated from 1977 to 2016.
Here we define the epitopes on HA that are targeted by a group of 9 recombinant monoclonal antibodies (rmAbs) isolated from memory B cells of mice, immunized by infection with A(H1N1)pdm09 virus followed by a seasonal TIV boost. These rmAbs were all reactive against the HA1 region of HA, but display 7 distinct binding footprints, targeting each of the 4 known antigenic sites. Although the rmAbs were not broadly cross-reactive, a group showed subtype-specific cross-reactivity with the HA of A/South Carolina/1/18.
View Article and Find Full Text PDFRespiratory syncytial virus (RSV) is the most common cause of serious lower respiratory illness in infants and young children worldwide, making it a high priority for development of strategies for prevention and treatment. RSV can cause repeat infections throughout life, with serious complications in elderly and immunocompromised patients. Previous studies indicate that the RSV G protein binds through a CX3C chemokine motif to the host chemokine receptor, CX3CR1, and modulates the inflammatory immune response.
View Article and Find Full Text PDFPurpose: Dasatinib is a dual Src/Abl inhibitor recently approved for Bcr-Abl+ leukemias with resistance or intolerance to prior therapy. Because Src kinases contribute to multiple blood cell functions by triggering a variety of signaling pathways, we hypothesized that their molecular targeting might lead to growth inhibition in acute myeloid leukemia (AML).
Experimental Design: We studied growth factor-dependent and growth factor-independent leukemic cell lines, including three cell lines expressing mutants of receptor tyrosine kinases (Flt3 or c-Kit) as well as primary AML blasts for responsiveness to dasatinib.
The newly described F-BAR (Fer/CIP4 and Bin, amphiphysin, Rvs) family of proteins includes Cdc42-interacting protein-4 (CIP4), formin-binding protein-17 (FBP-17) and transactivator of cytoskeletal assembly-1 (Toca-1), and drives membrane deformation and invagination. Membrane remodeling affects endocytosis, vesicle budding, and cargo selection. The F-BAR family presents a novel family of proteins, which little is known about their in vivo function.
View Article and Find Full Text PDFF-BAR proteins are a newly described family of proteins with unknown physiological significance. Because F-BAR proteins, including Cdc42 interacting protein-4 (CIP4), drive membrane deformation and affect endocytosis, we investigated the role of CIP4 in GLUT4 traffic by flow cytometry in GLUT4myc-expressing L6 myoblasts (L6 GLUT4myc). L6 GLUT4myc cells express CIP4a as the predominant F-BAR protein.
View Article and Find Full Text PDFTyrosine kinase inhibitors, such as imatinib, have dramatically improved the outcomes for patients with selected cancers. For imatinib, western blotting of phospho-CrkL was an insensitive, indirect, and descriptive method to determine drug efficacy. Greater use of targeted therapies should involve more quantitative evaluation of the target's dose-inhibition.
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