Immunology of Infectious Disease News Volume 1.15 | Jun 26 2013

Galectin-9 and IL-21 Mediate Cross-Regulation between Th17 and Regulatory T Cells during Acute Hepatitis C
The authors developed a combined proliferation/intracellular cytokine staining assay to monitor expansion of hepatitis C virus (HCV)-specific CD4 T cells and helper cytokines expression patterns during acute infections with different outcomes. They demonstrated that acute resolving HCV is characterized by strong Th1/Th17 responses with specific expansion of IL-21-producing CD4 T cells and increased IL-21 levels in plasma. [PLoS Pathog] Abstract

Lung-Resident CD4⁺ T Cells Are Sufficient for IL-4Ra-Dependent Recall Immunity to Nippostrongylus brasiliensis Infection
Immunity to Nippostrongylus brasiliensis reinfection requires pulmonary CD4⁺ T-cell responses. Scientists examined whether secondary lymphoid recruited or pre-existing lung CD4⁺ T-cell populations coordinated this immunity. [Mucosal Immunol] Abstract

ROS Induce Antiviral Innate Immune Response through Interferon-λ Regulation in Human Nasal Epithelial Cells
Investigators explored the role of interferon (IFN)-related innate immune response (IFN-ß, IFN-λ) and reactive oxygen species (ROS) after influenza A virus (IAV) infection for antiviral innate immune activity in normal human nasal epithelial cells that are highly exposed to IAV. [Am J Respir Cell Mol Biol] Abstract

Cryptopatches Are Essential for the Development of Human GALT
Abnormal gut-associated lymphoid tissue (GALT) in humans is associated with infectious and autoimmune diseases, which cause dysfunction of the gastrointestinal tract immune system. To investigate GALT pathologies in vivo, scientists bioengineered a human-mouse chimeric model characterized by the development of human GALT structures originating in mouse cryptopatches. [Cell Rep]
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HIV

Association of HLA-DRB1-Restricted CD4⁺ T Cell Responses with HIV Immune Control
The contribution of HLA class II-restricted CD4⁺ T cell responses to HIV immune control is poorly defined. The authors delineated previously uncharacterized peptide-DRB1 restrictions in functional assays and analyzed the host genetic effects of HLA-DRB1 alleles on HIV viremia in a large cohort of HIV controllers and progressors. [Nat Med] Abstract

Genistein Interferes with SDF-1- and HIV-Mediated Actin Dynamics and Inhibits HIV Infection of Resting CD4 T Cells
Researchers found that a tyrosine kinase inhibitor, genistein, inhibited both SDF-1-mediated chemotaxis and HIV infection of resting CD4 T cells. Genistein was also found to interfere with SDF-1- and HIV-mediated actin dynamics in CD4 T cells. [Retrovirology] Abstract | Full Article

Immune Activation and Regulation in SIV-P. Fragile Co-Infected Rhesus Macaques
Using a rhesus macaque model of SIV-P. fragile co-infection, researchers evaluated how innate immune effector cells affect the balance between immune activation and regulation. In vitro TLR responses of peripheral blood myeloid dendritic cells and monocytes were temporarily associated with acute parasitemic episodes and elevated plasma IL-10. [J Virol] Abstract

Interactions between Tenofovir and Nevirapine in CD4+ T Cells and Monocyte-Derived Macrophages Restrict Their Intracellular Accumulation
Researchers showed that tenofovir and nevirapine immune cell intracellular concentrations are lower when coincubated in CD4+ cells and monocyte-derived macrophages, but not in CD14+ cells. [J Antimicrob Chemother] Abstract

Impaired T-Cell Proliferation among Highly Active Antiretroviral Therapy (ART)-Treated Adults with Suboptimal CD4 Recovery in an African Cohort
The authors evaluated CD4 T-cell proliferation among suboptimal responders and its correlation with CD4 T-cell activation. The magnitude of CD4 increase (difference between absolute CD4 counts at baseline and absolute CD4 counts at four years of ART) was grouped into four quartiles for the 211 patients with sustained HIV-RNA viral suppression. [BMC Immunol] Abstract | Full Article

Resident Viruses and Their Interactions with the Immune System
Scientists explore how resident viruses interact with the immune system. They review recent findings that highlight the role of the immune system in shaping the composition of the virobiota and consider how resident viruses may impact host immunity. Finally, they discuss the implications of virobiota-immune system interactions for human health. [Nat Immunol] Abstract

CD8⁺ T-Cell Effector Function and Transcriptional Regulation during HIV Pathogenesis
The authors discuss the evidence for CD8⁺ T cells as correlates of protection, the means by which their antiviral capacity is evaluated, and transcription factors responsible for their function, or dysfunction, during human immunodeficiency virus (HIV) infection. [Immunol Rev] Abstract

Immune Activation and HIV Persistence: Implications for Curative Approaches to HIV Infection
Chronic human immunodeficiency virus (HIV) production or replication might contribute to persistent inflammation and immune dysfunction. The rapidly evolving data on these issues strongly suggest that a vicious cycle might exist in which HIV persistence causes inflammation that in turn contributes to HIV persistence. [Immunol Rev] Abstract

Visit our reviews page to see a complete list of reviews in the infectious disease research field.

NIH Awards $13M-Plus for UConn Immunology Research
The UConn Health Center has been awarded a grant of more than $13 million from the National Institutes of Health (NIH) to study pathogens, their products, and our immune responses to them. The target viral and bacterial pathogens are the influenza virus, listeria, salmonella, and staphylococcal toxins. The grant, from the NIH’s National Institute of Allergy and Infectious Diseases, covers years 8-12 of the project “Modulation of Biodefense Responses to Microbial Pathogens.” [University of Connecticut] Press Release

From our sponsor: Learn how ex vivo models drive progress in HIV research. Read the research profiles.