Biology subjects

Claudio, N. M.

Publications and source records attributed to Claudio, N. M..

3 recordsLinked to original sources

bioRxiv2023

Sequential chromogenic immunohistochemistry: spatial analysis of lymph nodes identifies contact interactions between plasmacytoid dendritic cells and plasmablasts

Recent clinical observations highlight the importance of the spatial organization of immune cells into lymphoid structures for the success of cancer immunotherapy and patient survival. Sequential chromogenic immunohistochemistry (scIHC) supports the analysis of multiple biomarkers on a single tissue section thus providing unique information about relative location of cell types and assessment of disease states. Unfortunately, widespread implementation of scIHC is limited by lack of a standardized, rigorous guide to the development of customized biomarker panels and by the need for user-friendly analysis pipelines able to streamline the extraction of meaningful data. Here, we examine major steps from classical IHC protocols and highlight the impact they have on the scIHC procedure. We report practical examples and illustrations of the most common complications that can arise during the setup of a new biomarker panel and how to avoid them. We described in detail how to prevent and detect cross- reactivity between secondary reagents and carry over between detection antibodies. We developed a novel analysis pipeline based on non-rigid tissue deformation correction, Cellpose-inspired automated cell segmentation and computational network masking of low-quality data. The resulting biomarker panel and pipeline was used to study regional lymph nodes from head and neck cancer patients. We identified contact interactions between plasmablasts and plasmacytoid dendritic cells in vivo. Given that TLR receptors, which are highly expressed in plasmacytoid dendritic cells play a key role in vaccine efficacy, the significance of this cell-cell interaction decisively warrants further studies. In conclusion, this work streamlines the development of novel biomarker panels for scIHC, which will ultimately improve our understanding of immune responses in cancer.

pathology↗

bioRxiv2022

Senescent cell-derived extracellular vesicles recruit antigen presenting cells and limit squamous carcinoma recurrence

Extracellular vesicles (EVs) are key signaling mediators. To explore the role of senescent cell-derived extracellular vesicles (senEVs) in inflammatory responses to senescence, we developed an engraftment-based senescence model in wild-type mice and genetically blocked senEV release in vivo, without significantly affecting soluble mediators. Our results demonstrate that senEVs are both necessary and sufficient to trigger immune-mediated clearance of senescent cells, thereby suppressing tumor growth. In the absence of senEVs, the recruitment of MHC-II+ antigen-presenting cells to the senescence microenvironment was markedly impaired. Blocking senEV release redirected the primary target of senescent cell signaling from antigen-presenting cells to neutrophils. Through comprehensive transcriptional and proteomic analyses, we identified six ligands specific to senEVs, highlighting their role in promoting antigen-presenting cell-T cell adhesion and synapse formation. Antigen-presenting cells activated CCR2+CD4+ TH17 cells, which appeared to inhibit B cell activation. CD4 T cells were essential for preventing tumor recurrence, indicating that CCR2+ TH17 cells function downstream of senEVs during senescence surveillance. Our findings suggest that senEVs complement the activity of secreted inflammatory mediators by recruiting and activating distinct immune cell subsets, thereby enhancing the efficient clearance of senescent cells. These conclusions may have implications not only for tumor recurrence but also for understanding senescence during de novo carcinogenesis. Consequently, this work could inform the development of novel cancer early detection strategies based on the biology of cellular senescence.

cancer biology↗

bioRxiv2022

Cancer stem cell-derived extracellular vesicles preferentially target MHCII- macrophages and PD1+ T cells in the tumor microenvironment

Immunotherapy is an approved treatment option for head and neck squamous cell carcinoma (HNSCC). However, the response rate to immune checkpoint blockade is only 13% for recurrent HNSCC, highlighting the urgent need to better understand tumor-immune interplay, with the ultimate goal of improving patient outcomes. HNSCC present high local recurrence rates and therapy resistance that can be attributed to the presence of cancer stem cells (CSC) within tumors. CSC exhibit singular properties that enable them to avoid immune detection and eradication. The immune cell types that directly engage with CSC to allow immune escape and cancer recurrence are still unknown. Here, we genetically engineered CSC-derived extracellular vesicles (EVs) to perform sortase-mediated in vivo proximity labeling. We identified specific immune cell subsets recruited into the CSC niche. We demonstrated that unmanipulated CSC-EVs preferentially target MHC-II- macrophages and PD1+ T cells, and that such EV-mediated intercellular communication between CSC and these immune cells contributed to the observed spatial interactions and niche sharing. These results suggest that combination therapies targeting CSC, tumor macrophages and PD1 may synergize and lower local recurrence rates in HNSCC patients.

cancer biology↗