Adaptation of Innate Lymphoid Cells to a Micronutrient Deficiency Promotes Type 2 Barrier Immunity The authors found that type 3 innate lymphoid cells are severely diminished in vitamin A-deficient settings, which results in compromised immunity to acute bacterial infection. [Science] Abstract G-CSF Drives a Posttraumatic Immune Program that Protects the Host from Infection The authors found that thermal injury to the skin induced a robust time-dependent protection of mice from a lethal Klebsiella pneumoniae pulmonary challenge. The protective response was neutrophil dependent and temporally associated with a systemic increase in neutrophils resulting from a reprioritization of hematopoiesis toward myeloid lineages. [J Immunol] Abstract The Immune Profile Associated with Acute Allergic Asthma Accelerates Clearance of Influenza Virus To further study influenza virus pathogenesis in allergic hosts, investigators aimed to develop and characterize murine models of asthma and influenza comorbidity to determine structural, physiological and immunological changes induced by influenza in the context of asthma. [Immunol Cell Biol] Abstract Porphyromonas gingivalis Infection Reduces Regulatory T Cells in Infected Atherosclerosis Patients Whether P.gingivalis infection is associated with regulatory T cells (Tregs) dysregulation during atherosclerosis (AS) is still unknown and the prevalence of different P.gingivalis FimA genotypes during this process is unclear. Researchers analyzed the distribution of Tregs and in P.gingivalis-infected atherosclerotic patients to reveal the relationship between P.gingivalis infection and Tregs reduction/dysfunction and to elucidate their role in periodontitis-AS interaction. [PLoS One] Full Article HIV Persistent HIV-1 Replication Is Associated with Lower Antiretroviral Drug Concentrations in Lymphatic Tissues Researchers showed in lymph node samples obtained before and during 6 months of treatment that the tissue concentrations of five of the most frequently used antiretroviral drugs are much lower than in peripheral blood. These lower concentrations correlated with continued virus replication measured by the slower decay or increases in the follicular dendritic cell network pool of virions and with detection of viral RNA in productively infected cells. [Proc Natl Acad Sci USA] Abstract | Press Release Preservation of Tetherin and CD4 Counter-Activities in Circulating Vpu Alleles despite Extensive Sequence Variation within HIV-1 Infected Individuals. Single genome analysis of vpu repertoires throughout infection in 14 individuals infected with HIV-1 clade B revealed extensive amino acid diversity of the Vpu protein. For the most part, this variation in Vpu increases over the course of infection and is associated with predicted epitopes of the individual’s MHC class I haplotype, suggesting CD8+ T cell pressure is the major driver of Vpu sequence diversity within the host. [PLoS Pathog] Full Article HIV Nef Expression Favors the Relative Preservation of CD4+ T Regulatory Cells that Retain Some Important Suppressive Functions Using the CD4C/HIV-1Nef transgenic mice as a model, the authors report that HIV-1 Nef causes depletion of total CD4+ T cells, but preserves and relatively enriches CD4+ regulatory T cells. [J Immunol] Abstract Soluble HIV-1 Envelope Immunogens Derived from an Elite Neutralizer Elicit Cross-Reactive V1V2 Antibodies and Low Potency Neutralizing Antibodies Scientists evaluated four gp140 Envelope protein vaccine immunogens that were derived from an elite neutralizer, subject VC10042, whose plasma was able to potently neutralize a wide array of genetically distinct HIV-1 isolates. [PLoS One] Full Article | Press Release How HIV-1 Nef Hijacks the AP-2 Clathrin Adaptor to Downregulate CD4 The Nef protein of HIV-1 downregulates the cell surface co-receptor CD4 by hijacking the clathrin adaptor complex AP-2. The structural basis for the hijacking of AP-2 by Nef is revealed by a 2.9 Ã… crystal structure of Nef bound to the α and σ2 subunits of AP-2. Nef binds to AP-2 via its central loop (residues 149-179) and its core. [eLIFE] Full Article | Press Release |