Flagellin stopped rotavirus by rapidly inducing an immune response that would normally be activated by select bacteria rather than a virus. Flagellin triggered the innate immune system, which provides an immediate response to pathogens, to produce two proteins: Interleukin-22, which prevented the virus from entering cells, and Interleukin-18, which removed existing rotavirus from infected cells. [Press release from Georgia State University discussing online prepublication in Science] Press Release | Abstract
Scientists demonstrate that human and mouse noroviruses infected B cells in vitro and likely in vivo. Human norovirus infection of B cells required the presence of histo-blood group antigen-expressing enteric bacteria. Mouse norovirus replication was reduced in vivo when the intestinal microbiota was depleted by means of oral antibiotic administration. [Science] Abstract | Press Release
Cutaneous Innate Immune Sensing of Toll-like Receptor 2-6 Ligands Suppresses T Cell Immunity by Inducing Myeloid-Derived Suppressor Cells
Researchers found suppression of immune responses due to cutaneous infection with Gram-positive S. aureus, which was based on bacterial lipopeptides. Skin exposure to Toll-like receptor (TLR)2-6-binding lipopeptides, but not TLR2-1-binding lipopeptides, potently suppressed immune responses through induction of Gr1+CD11b+ myeloid-derived suppressor cells. [Immunity] Abstract | Graphical Abstract | Press Release
Investigators show that hepatitis C virus (HCV)-specific T cells induced by ChAd3 are optimally boosted with modified vaccinia Ankara (MVA), and generate very high levels of both CD8+ and CD4+ HCV-specific T cells targeting multiple HCV antigens. [Sci Transl Med] Abstract | Press Release
The Staphylococcal Toxins γ-Hemolysin AB and CB Differentially Target Phagocytes by Employing Specific Chemokine Receptors
Researchers identified the chemokine receptors ​CXCR1, ​CXCR2 and ​CCR2 as targets for γ-hemolysin AB, and the complement receptors ​C5aR and ​C5L2 as targets for γ-hemolysin CB. The receptor expression patterns allow the toxins to efficiently and differentially target phagocytic cells. [Nat Commun] Abstract
Scientists investigated whether nucleotide-binding domain and leucine rich repeat pyrin containing (NLRP)3 and/or apoptosis-associated speck-like protein containing a CARD (ASC) were required for caspase-1 activation upon lethal toxin stimulation in the BALB/c background. The NLRP1b inflammasome activation was assessed in both macrophages and dendritic cells lacking either ASC or NLRP3. [Proc Natl Acad Sci USA]
As chronic infection with RNA viruses such as human immunodeficiency virus type 1 (HIV-1) induces profound dysfunction of CD4+ T cells, researchers investigated the role of Toll-like receptor (TLR)7-induced anergy in HIV-1 infection. [Nat Immunol] Abstract
Investigators performed a single arm, open label, proof-of-concept study in which vorinostat, a pan-human immunodeficiency virus (HIV) latency and histone deacetylase inhibitor, was administered orally once daily for 14 days to 20 HIV-infected individuals on suppressive antiretroviral therapy. [PLoS Pathog] Full Article
Researchers quantified the susceptibility of naïve and memory CD4+ T-cell subsets, including stem cell memory T-cells, to infection by HIV-1 subtype C strains from treatment-naïve subjects who progressed from chronic to advanced stages of disease whilst either maintaining CCR5-using viruses, or who experienced emergence of dominant CXCR4-using strains. [Retrovirology] Full Article
HIV-Specific ADCC Improves after Antiretroviral Therapy and Correlates with Normalization of the NK Cell Phenotype
Scientists investigated natural killer (NK) cell function, as measured by antibody-dependent cellular cytotoxicity (ADCC), in HIV-1 positive individuals before and six months after highly active antiretroviral therapy (HAART) initiation. [J Acquir Immune Defic Syndr] Abstract
Scientists found that during progressive HIV-1 infection plasmacytoid dendritic cells (pDCs) were depleted in peripheral blood compared to seronegative controls, and, correlating with plasma viremia, the remaining pDCs upregulated the gut-homing marker, α4β7. [AIDS Res Hum Retroviruses] Abstract
Recent studies of HIV-positive patients with strongly neutralizing sera have shown that the human immune system is capable of producing potent and broadly neutralizing antibodies, some of which neutralize up to 90% of HIV strains. The use of engineered glycoproteins and other glycostructures as vaccines to elicit antibodies with broad neutralizing activity is a key area of interest in HIV vaccine design. [Nat Chem Biol] Abstract
ADMA Biologics, Inc. announced data describing the composition and efficacy in an animal model of its polyclonal IVIG product, RI-002. [Press release from ADMA Biologics, Inc. discussing research presented at the 9th International RSV Symposium, Cape Town] Press Release | Poster
For HIV-infected women in good immune health, taking a three-drug regimen during pregnancy prevents mother-to-child HIV transmission more effectively than taking one drug during pregnancy, another during labor and two more after giving birth. [The National Institutes of Health (NIH)] Press Release
The grant includes three University of Alabama at Birmingham (UAB) labs working with mouse models and one lab at the University of California-Davis. It also includes a series of human experiments run at Emory University. The UAB grant focus is viral-induced cell-fate decisions in anti-viral immunity. [University of Alabama at Birmingham] Press Release
Mairi Noverr, PhD has been awarded a $1.8 million grant by the National Institute of Allergy and Infectious Diseases. The funding will support research to reduce the death rate from intra-abdominal infections caused by both fungal and bacterial pathogens. [Louisiana State University Health Sciences Center (EurekAlert)] Press Release
Dr. Marc Pellegrini is one of three researchers to be awarded a 2014 Sylvia and Charles Viertel Charitable Foundation Senior Medical Research Fellowship. Pelligrini said the five-year fellowship would allow him to focus on progressing his research into chronic infections such as HIV, hepatitis B and tuberculosis. [The Walter and Eliza Hall Institute of Medical Research] Press Release