Immunology of Infectious Disease News Volume 1.18 | Jul 17 2013

CD40 Activation Rescues Antiviral CD8⁺ T Cells from Programmed Death 1-Mediated Exhaustion
The intrahepatic immune environment is normally biased towards tolerance. Nonetheless, effective antiviral immune responses can be induced against hepatotropic pathogens. To examine the immunological basis of this paradox researchers studied the ability of hepatocellularly expressed hepatitis B virus (HBV) to activate immunologically naïve HBV-specific CD8⁺ T cell receptor transgenic T cells after adoptive transfer to HBV transgenic mice. [PLoS Pathog] Full Article

Decreased Vδ2 γδ T Cells Associate with Liver Damage through Regulating Th17 Response in Chronic Hepatitis B Patients
γδ T cells comprise a small subset of T cells and play a protective role against cancer and viral infections; however, their precise role in patients with chronic hepatitis B remains unclear. Flow cytometry and immunofunctional assays were performed to analyze the impact of Vδ2 γδ T cells in 64 immune-activated patients, 22 immune-tolerant carriers and 30 healthy controls. [J Infect Dis] Abstract

Pathways of IL-1β Secretion by Macrophages Infected with Clinical Mycobacterium tuberculosis Strain
The authors investigated the primary pathways of interleukin (IL-1β) secretion in macrophages infected with a panel of 17 clinical M. tuberculosis isolates, representing Euro-American, Indo-Oceanic and East-Asian/Beijing lineages. They aimed to dissect the pathways involved in M. tuberculosis induced IL-1β secretion and to determine whether they are common to all clinical isolates. [Tuberculosis]
Abstract | Press Release

An Attenuated Temperature-Sensitive Strain of Cytomegalovirus (tsm5) Establishes Immunity without Development of CD8⁺ T Cell Memory Inflation
Using murine cytomegalovirus, researchers showed that memory inflation of virus-specific CD8⁺ T cells is avoided if mice are infected with a replication defective virus called temperature-sensitive mutant 5 (tsm5), which carries an attenuating mutation within the DNA primase gene. Mice infected with tsm5 do generate primary T cell responses towards viral proteins but these do not amass to skew the memory repertoire of CD8⁺ T cells. [J Med Virol] Abstract

HIV

Dysbiosis of the Gut Microbiota Is Associated with HIV Disease Progression and Tryptophan Catabolism
Using high-resolution bacterial community profiling, the authors identified a dysbiotic mucosal-adherent community enriched in Proteobacteria and depleted of Bacteroidia members that was associated with markers of mucosal immune disruption, T cell activation, and chronic inflammation in HIV-infected subjects. [Sci Transl Med] Abstract | Press Release | Video

Rapid Perturbation in Viremia Levels Drives Increases in Functional Avidity of HIV-Specific CD8 T Cells
Researchers investigated HIV-specific CD8 T cell responses in 85 patients with primary HIV infection or chronic (progressive and non-progressive) infection. The functional avidity of HIV-specific CD8 T cells was not different between patients with progressive and non-progressive chronic infection. [PLoS Pathog]
Full Article

Safety and Comparative Immunogenicity of an HIV-1 DNA Vaccine in Combination with Plasmid Interleukin 12 and Impact of Intramuscular Electroporation for Delivery
The human immunodeficiency virus type 1 (HIV-1) PENNVAX®-B DNA vaccine is a mixture of three expression plasmids encoding HIV-1 Clade B Env, Gag, and Pol. The interleukin 12 (IL-12) DNA plasmid expresses human IL-12 proteins p35 and p40. Study subjects were healthy HIV-1-uninfected adults 18-50 years old. Four intramuscular vaccinations were given in HVTN 070, and three intramuscular vaccinations were followed by electroporation in HVTN 080. Cellular immune responses were measured by intracellular cytokine staining after stimulation with HIV-1 peptide pools. [J Infect Dis] Abstract | Press Release

The HIV-1 Protein Vpr Targets the Endoribonuclease Dicer for Proteasomal Degradation to Boost Macrophage Infection
Investigators identified the endoribonuclease Dicer as a target of HIV-1 Vpr-directed proteasomal degradation through CRL4DCAF1. They showed that HIV-1 Vpr inhibits short hairpin RNA function as expected upon reduction of Dicer levels. Dicer inhibits HIV-1 replication in T cells. [Virology] Abstract

Hepatitis B Virus (HBV)-Specific T-Cell Responses to Recombinant HBV Core Protein in Patients with Normal Liver Function and Co-Infected with Chronic HBV and Human Immunodeficiency Virus 1 (HIV-1)
Twenty-five patients with chronic HBV were enrolled in a cross-sectional study. A longitudinal study was also conducted in which follow-up was done at 3, 12, and 24 months, after acute HIV-1 infection, in 11 individuals who also had chronic HBV. Peripheral blood mononuclear cells were stimulated with recombinant HBV surface protein, core protein or gag peptide. IFN-gamma-secreting T cells were identified by ELISPOT assay. [Virol J] Abstract | Full Article

Innate Immune Response to La Crosse Virus Infection
The authors discuss the current understanding of innate immune response in the context of viral pathogenesis and host susceptibility to La Crosse virus (LACV). In addition, they address the need for a clearer understanding of the early host-virus interactions in LACV infections as it relates to viral pathogenesis in the central nervous system. [J Neurovirol] Abstract

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

From our sponsor:
View immunology lectures, protocols and other resources on the Human Immunology Portal.

Medicago Announces Agreement to Be Acquired by Mitsubishi Tanabe Pharma in a Transaction Valued at $357 Million
Medicago Inc., a biopharmaceutical company focused on developing highly effective and competitive vaccines based on proprietary manufacturing technologies and virus-like particles, announced that it has entered into a definitive arrangement agreement with Mitsubishi Tanabe Pharma Corporation (MTPC) whereby MTPC will acquire all of the issued and outstanding common shares (Shares) of Medicago, other than the Shares currently held by Philip Morris Investments B.V. an affiliate of Philip Morris International Inc. and MTPC, for $1.16 in cash per Share. [Medicago Inc.] Press Release

Ruth Ruprecht, a Pioneer in AIDS-Related Research and Vaccines, and in Breast Cancer, Is Appointed to Virology Position at Texas Biomed
Ruth M. Ruprecht, M.D., Ph.D., a professor of medicine at Harvard Medical School and the Dana-Farber Cancer Institute in Boston, has been appointed to the position of Scientist and Director of the AIDS Research Program in the Department of Virology and Immunology at the Texas Biomedical Research Institute. [Texas Biomedical Research Institute] Press Release

Food and Drug Administration (United States)

Center for Biologics Evaluation and Research (United States)

European Medicines Agency (European Union)

Medicines and Healthcare Products Regulatory Agency (United Kingdom)

Therapeutic Goods Administration (Australia)

Visit our events page to see a complete list of events in the infectious disease community.

Postdoctoral Position – Virus Host Interactions (CIBIO – University of Trento)

Postdoctoral Scientist – Humoral Responses against HIV (Seattle BioMed)

Director of Cell Processing Facility (S L Collins Associates, Inc.)

Research Scientist/Senior Research Officer – Monoclonal Antibodies (Bioprocessing Technology Institute/A*STAR)

Postdoctoral Fellow – Immune Responses against HIV (HIV Pathogenesis Program/University KwaZulu Natal & Ragon Institute of MGH, MIT and Harvard)

Junior or Senior Group Leader – Immunology/Infection/Inflammation (Center of Pathophysiology of Toulouse Purpan)

Recruit Top Talent: Reach more than 50,000 potential candidates by posting your organization’s career opportunities on the Connexon Creative Job Board at no cost.