Poster H1 - Spatial Multomics Profiling of Angioimmunoblastic T-cell lymphoma

Saturday, October 26, 2024

10:00 AM – 11:00 AM EST

Location: Exhibit Hall E, F & G

Presenting Author(s)

Ezabella Teka (she/her/hers)

Undergraduate Student
Yale University
Wooster, Ohio, United States

Co-Author(s)

archibald enninful

PhD Student
Yale University
New Haven, Connecticut, United States

Last Author(s)

RF

Rong Fan

Harold Hodgkinson Professor
Yale University
New Haven, Connecticut, United States

Primary Investigator(s)

Mina Xu, MD

Professor
Yale School of Medicine, United States

Introduction: Angioimmunoblastic T-cell lymphoma (AITL) is a subtype of non-Hodgkin’s lymphoma (NHL), specifically, peripheral T-cell lymphoma (PTCL) and is attributed to the abnormal proliferation of T follicular helper cell (TFH) phenotype. It is characterized by intense inflammatory and immune reactions. AITL presents with a highly complex tumor microenvironment with the tumor cells on a scaffold of highly proliferating CD21+ follicular dendritic cells found in proximity with high endothelial venules (HEVs). The organized structure of the lymph node with distinct B cell and T cell zones is disrupted in the lymph node samples from patients with AITL. Although AITL is very rare and accounts for only 1% to 2% of all NHLs, it is important to understand its transcriptional and proteomic landscape to improve clinical outcomes for patients. Based on prior literature in this space, background “benign” inflammatory bystanders and abnormal non-neoplastic vasculature and stromal cells allow for tumor cells to escape immune surveillance and unchecked proliferation. We hypothesize that spatial characterization of the interactions within the tumor microenvironment may lead to improved targeting of these tumor enablers.

Materials and

Methods: In this study,10 µm thick tissue sections on poly-L-lysine coated slides were prepared from archived FFPE tissue blocks by the Yale Pathology Tissue Services (YPTS). Hematoxylin and Eosin (H&E) staining was done on 1 slide. Next, DBIT-Seq (a microfluidics-based spatial transcriptomics approach) was performed to map the transcriptome and was sequenced on an Illumina NovaSeq 6000 platform with 150bp paired-end read length by Novogene corporation. On an adjacent tissue, we performed multiplexed immunofluorescence imaging (CODEX) for 38 cell-type specific markers as well as AITL markers in our panel (listed in Table 1) using the PhenoCycler-Fusion system. Cell segmentation was performed using QuPath and downstream analysis done using the Seurat package.

Results, Conclusions, and Discussions: From the histological staining (H&E), we were able to observe the distinct spatial organization of lymph nodes in AITL. We observed a scaffold of follicular dendritic cells that were very close to the vasculature. As compared to the organized structure of the lymph node with distinct B cell and T cell zones, we observed a disruption of this organization in the lymph node samples from patients with AITL. From the multiplexed immunofluorescence data, we were able to identify distinct cell types based on their cell type markers. For example, the vascular endothelial cells were identified by their expression of CD31 and proximal location to the tumor cells which are of T follicular helper cell origin. Following cell segmentation with a StarDist-based method and clustering using Seurat V5, we observed 14 distinct clusters and their differentially expressed proteins from the heatmap from which annotation of the clusters was done. By utilizing spatial multiplexed immunofluorescence (CODEX), we profiled a lymph node from a patient with AITL. The 38 cell-type markers allowed us to identify the cell types within the tumor microenvironment. Further analysis and spatial characterization of the interactions of the tumor microenvironment may lead to improved targeting of these tumor enablers that allow the tumor cells to escape immune surveillance and unchecked proliferation.

Acknowledgements (Optional): Yale Biomedical Engineering Department
Yale Pathology Tissue Services
Human BioMolecular Atlas program