Search bioRxiv⌕ Search

bioRxiv · 10.1101/2023.12.05.570256

Unraveling the role of γδ T cells in the pathogenesis of an oncogenic avian herpesvirus

Abstract

Mareks disease virus (MDV) is an oncogenic alphaherpesvirus that causes deadly T cell lymphomas in chickens. MDV is highly cell associated which allows the virus to evade antibody-mediated virus neutralization. Therefore, T cell-mediated immune responses are thought to be crucial for combating this deadly pathogen. In chickens, gamma delta ({gamma}{delta}) T cells represent a major population with up to 50% of all peripheral T cells. However, their role in MDV pathogenesis and tumor formation remains poorly understood. To investigate the role of {gamma}{delta} T cells in MDV pathogenesis, we infected genetically modified chickens that lack {gamma}{delta} T cells (TCR C{gamma}-/-) with very virulent MDV. Strikingly, disease and tumor incidence were highly increased in the absence of {gamma}{delta} T cells, indicating that {gamma}{delta} T cells play an important role in the immune response against MDV. In the absence of {gamma}{delta} T cells, virus replication was increased by up to 89-fold in the thymus and spleen, both potential sites of T cell transformation. Taken together, our data provide the first evidence that {gamma}{delta} T cells play an important role in restricting MDV replication, pathogenesis and tumors caused by this deadly pathogen. Author Summary{gamma}{delta} T cells are the most abundant T cells in chickens, but their role in fighting pathogens remains poorly understood. Mareks disease virus (MDV) is an important veterinary pathogen, causes one of the most frequent cancers in animals and is used as a model for virus-induced tumor formation. Our study revealed that {gamma}{delta} T cells play a crucial role in combating MDV, as disease and tumor incidence was drastically increased in the absence of these cells. {gamma}{delta} T cells restricted virus replication in the key lymphoid organs, thereby decreasing the likelihood of causing tumors and disease. This study provides novel insights into the role of {gamma}{delta} T cells in the pathogenesis of this highly oncogenic virus.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Sabsabi, M. A., Kheimar, A., You, Y., von La Roche, D., Härtle, S., Göbel, T. W., von Heyl, T., Schusser, B., Kaufer, B. B.. 2023-12-06. Unraveling the role of γδ T cells in the pathogenesis of an oncogenic avian herpesvirus. https://doi.org/10.1101/2023.12.05.570256

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

A population-scale landscape of the subgingival microbiome reveals divergent routes to periodontal dysbiosis

Periodontitis is an archetypical mucosal inflammatory disease in which microbiome dysbiosis at the tooth-epithelial interface interacts with host genetic and behavioral risk factors to drive immune-mediated tissue destruction. Although subgingival microbiome compositional shifts are thought to parallel disease severity, microbiome variation at the population-level and its relationship to periodontal clinical phenotypes and disease-modifying factors remain poorly defined. Here, we use unsupervised manifold learning to map the compositional landscape of the subgingival microbiome in 1,355 adults spanning periodontal health to severe periodontitis. We identified eight latent microbiome states organized along a branching continuum from eubiosis to dysbiosis. An intermediate microbial configuration marked ecological destabilization and bifurcation into two distinct periodontitis-associated dysbiotic trajectories, distinguished by links to gingival inflammation and smoking. Although the microbiome trajectories broadly tracked periodontal destruction, a minority of individuals showed discordant microbiome-clinical phenotypes, with some individuals with periodontitis retaining otherwise eubiotic microbiomes enriched for low-abundance pathobionts, while some cases of health or mild disease had highly dysbiotic communities, suggesting distinct host susceptibility. Together, these findings define a population-scale ecological landscape of the subgingival microbiome, reveal divergent trajectories to periodontal dysbiosis, and highlight heterogeneity in the relationship between microbial community structure and clinical disease expression.

microbiology↗

The iron-binding siderophore enterobactin is required for the response of multi-drug resistant Klebsiella pneumoniae to zinc limitation

To persist during infection Klebsiella pneumoniae must overcome nutrient iron and zinc limitation imposed by the host immune system through a process called nutritional immunity. Secreted small molecule siderophores are a major virulence determinant of Klebsiella pneumoniae pathogenesis and are presumed to overcome nutritional immunity by binding iron for bacterial acquisition. In this work, we set out to identify how a multi-drug resistant K. pneumoniae grows in zinc limited environments. Using unbiased transcriptomics, proteomics, and an arrayed transposon screen, we identified that synthesis and uptake of the siderophore enterobactin is required to allow for growth in low zinc conditions. Iron-specific chelators did not replicate this phenotype and addition of supplemental iron through heme in growth media could not complement severe growth defects of enterobactin mutant K. pneumoniae experiencing zinc limitation. Finally, zinc starvation induced enterobactin production independent of the canonical zinc uptake regulator (Zur) transcription factor suggesting an unidentified regulatory mechanism by which Gram-negative pathogens may respond to zinc stress. Together, these studies expand the role of enterobactin beyond iron regulation and highlight a previously unreported link between iron and zinc homeostasis in Klebsiella pneumoniae.

microbiology↗

A microbiota-derived protease links phage susceptibility to host epithelial responses

Bacteriophages are major ecological drivers of gut microbial ecology, yet whether bacterial mechanisms that determine phage susceptibility have consequences for the mammalian host remains poorly understood. Here, we identify dipeptidyl peptidase 11 (Dpp11a), the predominant active serine protease of the prevalent gut commensal Phocaeicola vulgatus, as an unexpected bacterial defence factor. Dpp11a protects against environmental proteases and confers resistance to bacteriophage infection. Metatranscriptomic analyses further reveal increased expression of both dpp11a and P. vulgatus-associated phage transcripts in ulcerative colitis stool samples, indicating that both components of this interaction are transcriptionally active in disease-associated human microbiomes. Using the microfluidic gut-on-a-chip co-culture model HuMiX, we show that the absence of Dpp11 is accompanied by altered epithelial tight-junction remodelling during phage-bacterial infection. Together, our findings reveal that the consequences of bacterial phage defence can extend beyond phage-bacterium interactions to the mammalian epithelium.

microbiology↗