Multimodal immune cell phenotyping in GI biopsies reveals microbiome-related T cell modulations in human GvHD

Acute graft-versus-host disease (aGvHD) is a significant complication after allogeneic hematopoietic stem cell transplantation (aHSCT), but major factors determining disease severity are not well defined yet. By combining multiplexed tissue imaging and single-cell RNA sequencing on gastrointestinal biopsies from aHSCT-treated individuals with fecal microbiome analysis, we link high microbiome diversity and the abundance of short-chain fatty acid-producing bacteria to the sustenance of suppressive regulatory T cells (Tregs). Furthermore, aGvHD severity strongly associates with the clonal expansion of mainly CD8 T cells, which we find distributed over anatomically distant regions of the gut, persistent over time, and inversely correlated with the presence of suppressive Tregs. Overall, our study highlights the pathophysiological importance of expanded CD8 T cell clones in the progression of aGvHD toward more severe clinical manifestations and strongly supports the further development of microbiome interventions as GvHD treatment via repopulation of the gut Treg niche to suppress inflammation.

ChipCytometry for multiplexed detection of protein and mRNA markers on human FFPE tissue samples

In this protocol, we describe the use of ChipCytometry to combine RNA in situ hybridization and antibody staining for multiplexed tissue imaging of human formalin-fixed and paraffin-embedded tissue samples. The advantages of ChipCytometry are long-term storage for re-interrogation and advanced image quality by high dynamic range imaging of staining and background. A titrated pretreatment of tissue samples bypasses challenges because of the retrieval of antigens on coverslips and achieves an optimal staining quality at the minimal expense of tissue integrity.

For complete details on the use and execution of this protocol, please refer to Jarosch et al. (2021).

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This protocol describes use of ChipCytometry on human FFPE samples

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This protocol combines mRNA staining via FISH with multiplexed immunofluorescence

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This protocol provides an automatic image analysis pipeline for ChipCytometry data

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The automated analysis pipeline can be applied on any multiplexed imaging data

Multiplexed imaging and automated signal quantification in formalin-fixed paraffin-embedded tissues by ChipCytometry

Deciphering the spatial composition of cells in tissues is essential for detailed understanding of biological processes in health and disease. Recent technological advances enabled the assessment of the enormous complexity of tissue-derived parameters by highly multiplexed tissue imaging (HMTI), but elaborate machinery and data analyses are required. This severely limits broad applicability of HMTI. Here we demonstrate for the first time the application of ChipCytometry technology, which has unique features for widespread use, on formalin-fixed paraffin-embedded samples, the most commonly used storage technique of clinically relevant patient specimens worldwide. The excellent staining quality permits workflows for automated quantification of signal intensities, which we further optimized to compensate signal spillover from neighboring cells. In combination with the high number of validated markers, the reported platform can be used from unbiased analyses of tissue composition to detection of phenotypically complex rare cells, and can be easily implemented in both routine research and clinical pathology.