Single-cell RNA sequencing combined with multiplex immunofluorescence probes the role of MFAP5+ fibroblasts in the microenvironment of pancreatic ductal adenocarcinoma.

we employed single-cell RNA sequencing to examine the biological characteristics of MFAP5+ fibroblasts in PDAC and their interaction with vascular endothelial cells within tumors. We then utilized a proposed temporal sequencing analysis technique to infer the evolution of cellular subtypes of cancer-associated fibroblasts. To verify our hypothesis, we employed a multiplex immunofluorescence technique to observe the spatial distribution of MFAP5+ fibroblasts and endothelial cells. This study investigated the tumor heterogeneity of PDAC, elucidating intricate cellular interactions within the tumor microenvironment through a comprehensive analysis of 23,905 cells. The biology of MFAP5+ fibroblasts in pancreatic ductal adenocarcinoma was investigated, and it was found that MFAP5+ fibroblasts engage in active biosignaling exchanges with FABP4+ endothelial cells and other endothelial cells through the activation of key tumor-promoting signaling pathways, such as TGF-ß, VEGF, and FGF. These pathways provide support for the tumor's invasive and malignant behavior. Our hypothesis was validated by multiplex immunofluorescence and subsequent semi-quantitative analysis, which demonstrated a notable increase in the prevalence of FABP4+ and VWF+ endothelial cells in the area with elevated MFAP5+ fibroblast expression. Furthermore, our study revealed that vascular endothelial growth factor and FGF2 signaling were highly expressed in the region with high MFAP5+ fibroblast expression. Overall design: NOT PROVIDED; REQUESTED