Project description:Endobronchial ultrasound (EBUS) guided biopsy is becoming the mainstay for investigation of mediastinal lymphadenopathy to aid laboratory diagnosis of malignancy, sarcoidosis or tuberculosis. However, diagnostic uncertainty is still common in the distinction between culture negative tuberculosis and sarcoidosis or malignancy and reactive lymphadenitis. We sought to evaluate the role of genome-wide transcriptional profiling of EBUS guided lymph node samples to aid diagnostic processes in this setting.
Project description:The immune-suppressive features often possessed by invasive tumors hamper effective anti-tumor immunity. In this context, tumor-infiltrating regulatory T cells (Tregs) have been widely implied, principally as unwanted suppressors of anti-tumor immune responses. However, while many studies have focused on tumor-infiltrating Tregs, the function and signaling of Tregs in tumor-associated lymph nodes is largely unknown. In this study, we set out to clarify how immune signaling in lymph nodes is impacted by its contact to the tumour. Because muscle-invasive urothelial bladder cancer (MIBC) represent an immunogenic cancer were Tregs are accumulated and sentinel nodes (SNs) can be efficiently detected, we explored the protein expression of T-cells in SNs and non-SNs of MIBC patients. Proteomic analysis of Tregs and effector T-cells in SN and non-draining lymph nodes found SN-Tregs in MIBC patients to up-regulate growth and immune signaling pathways, the cytokine IL-16 being central in the signaling network. Experimental validation showed that in Tregs, tumoral factors increase IL-16 processing into bioactive forms and increase FOXP3 expression. In conclusion, altered IL-16 processing caused by tumour-released factors stimulate expansion of SN-Tregs in MIBC, creating an immunosuppressive environment and contributing to immune escape.
Project description:Expression profiles of porcine liver and tracheobronchial lung lymph node tissues were studied to identify genes being significantly affected by bacterial infection of the lungs. Samples were taken from liver and tracheobronchial lung lymph node tissues in pigs experimentally infected with A. pleuropneumoniae, serotype 5b, and from healthy non-inoculated control pigs from the same herd. Samples were investigated for changes in gene expression by means of global cDNA microarrays. Expression profiling of samples of liver and lung lymph node tissues from ten pigs challenged with Actinobacillus pleuropneumoniae and from five healthy control pigs was conducted by hybridising all 2x15 samples against a tissue specific common reference consisting of a pool of equal amount of total-RNA from all samples of each tissue type and were balanced with respect to control and challenged animals.
Project description:High endothelial venules (HEVs) play a crucial role in adaptive immune responses in secondary lymphoid organs (SLOs). They are uniquely equipped with high levels of peripheral node addressins (PNAd), harboring carbohydrate structures that serve as L-Selectin ligands to efficiently facilitate lymphocyte homing. During inflammation, the HEV network expands in SLOs, increasing lymphocyte infiltration, but the underlying mechanisms maintaining HEVs remain underexplored. Here, we report that autophagy is essential for HEV function and expansion. Using mass spectrometry, and an inducible HEV tracer system in mice, we demonstrate that autophagy deficiency compromises LTR-signaling and the unfolded protein response in HEVs, leading to disrupted PNAd production, dedifferentiation, and reduced lymphocyte homing.Our work uncovers an unprecedented role of autophagy in safeguarding HEV identity and function during inflammation.
Project description:n breast cancer (BC), detecting low volumes of axillary lymph node (ALN) metastasis pre-operatively is difficult and novel biomarkers are needed. We recently showed that patient-derived ALNs can be sustained ex-vivo using normothermic perfusion. We now compare reactive (tumour-free; n = 5) and macrometastatic (containing tumour deposits >2mm; n = 4) ALNs by combining whole section multiplex immunofluorescence with TMT-labelled LC-MS/MS of the circulating perfusate. Macrometastases contained significantly fewer B- and T-cells (CD4+/CD8+/regulatory) than reactive nodes (p = 0.02). Similarly, pathway analysis of the perfusate proteome (119/1453 proteins significantly differentially expressed) showed that immune function was diminished in macrometastases in favour of ‘extracellular matrix degradation’; only ‘neutrophil degranulation’ was preserved. Qualitative comparison of the perfusate proteome to that of node-positive pancreatic and prostatic adenocarcinoma also highlighted ‘neutrophil degranulation’ as a contributing factor to nodal metastasis. Thus, metastasis-induced changes in the REPLICANT perfusate proteome are detectable, and could facilitate biomarker discovery.