HIV-1 Accessory Protein Vpr Interacts with REAF/RPRD2 To Mitigate Its Antiviral Activity.

The human immunodeficiency virus type 1 (HIV-1) accessory protein Vpr enhances viral replication in both macrophages and, to a lesser extent, cycling T cells. Virion-packaged Vpr is released in target cells shortly after entry, suggesting it is required in the early phase of infection. Previously, we described REAF (RNA-associated early-stage antiviral factor; RPRD2), a constitutively expressed protein that potently restricts HIV replication at or during reverse transcription.

Differences in systemic adaptive immunity contribute to the 'frequent exacerbator' COPD phenotype.

Background: Some COPD patients are more susceptible to exacerbations than others. Mechanisms underlying these differences in susceptibility are not well understood. We hypothesized that altered cell mediated immune responses may underlie a propensity to suffer from frequent exacerbations in COPD.

PD1-Expressing T Cell Subsets Modify the Rejection Risk in Renal Transplant Patients.

We tested whether multi-parameter immune phenotyping before or after renal -transplantation can predict the risk of rejection episodes. Blood samples collected before and weekly for 3 months after transplantation were analyzed by multi-parameter flow cytometry to define 52 T cell and 13 innate lymphocyte subsets in each sample, producing more than 11,000 data points that defined the immune status of the 28 patients included in this study. Principle component analysis suggested that the patients with histologically confirmed rejection episodes segregated from those without rejection.

Genetic Regulation of Fate Decisions in Therapeutic T Cells to Enhance Tumor Protection and Memory Formation.

A key challenge in the field of T-cell immunotherapy for cancer is creating a suitable platform for promoting differentiation of effector cells while at the same time enabling self-renewal needed for long-term memory. Although transfer of less differentiated memory T cells increases efficacy through greater expansion and persistence in vivo, the capacity of such cells to sustain effector functions within immunosuppressive tumor microenvironments may still be limiting. We have therefore directly compared the impact of effector versus memory differentiation of therapeutic T cells in tumor-bearing mice by introducing molecular switches that regulate cell fate decisions via mTOR.

Clonotypic composition of the CD4+ T cell response to a vectored retroviral antigen is determined by its speed.

The mechanisms whereby different vaccines may expand distinct Ag-specific T cell clonotypes or induce disparate degrees of protection are incompletely understood. We found that several delivery modes of a model retroviral Ag, including natural infection, preferentially expanded initially rare high-avidity CD4(+) T cell clonotypes, known to mediate protection. In contrast, the same Ag vectored by human adenovirus serotype 5 induced clonotypic expansion irrespective of avidity, eliciting a predominantly low-avidity response.

Description of Endozoicomonas euniceicola sp. nov. and Endozoicomonas gorgoniicola sp. nov., bacteria isolated from the octocorals Eunicea fusca and Plexaura sp., and an emended description of the genus Endozoicomonas.

Two Gram-negative, facultatively anaerobic, rod-shaped bacteria, strains EF212(T) and PS125(T), were isolated from the octocorals Eunicea fusca and Plexaura sp., respectively. EF212(T) was isolated from a specimen of E.

Race between retroviral spread and CD4+ T-cell response determines the outcome of acute Friend virus infection.

Retroviruses can establish persistent infection despite induction of a multipartite antiviral immune response. Whether collective failure of all parts of the immune response or selective deficiency in one crucial part underlies the inability of the host to clear retroviral infections is currently uncertain. We examine here the contribution of virus-specific CD4(+) T cells in resistance against Friend virus (FV) infection in the murine host.