digestion-murine-liver-for-flow-cytometric-analysis-lymphatic

Digestion of the Murine Liver for a Flow Cytometric Analysis of Lymphatic Endothelial Cells

Within the liver, lymphatic vessels are found within the portal triad, and their described function is to remove interstitial fluid from the liver to the ...

University of Colorado Anschutz Medical Campus, School of Medicine

Antigens derived from viral infection or vaccination can persist within a host for many weeks after resolution of the infection or vaccine responses. We previously identified lymphatic endothelial cells (LEC) as the repository for this antigen archival, yet LECs are unable to present their archived antigens to CD8 T cells, and instead transfer their antigens to CD11c antigen-presenting cells (APC). Here we show that the exchange of archived antigens between LECs and APCs is mediated by migratory dendritic cells (DC). After vaccination, both migratory basic leucine zipper ATF-like transcription factor 3 (BatF3)-dependent and BatF3-independent DCs are responsible for antigen exchange and cross-presentation. However, exchange of archived viral antigens is mediated only by BatF3-dependent migratory DCs potentially acquiring apoptotic LECs. In conclusion, LEC-archived antigens are exchanged with migratory DCs, both directly and through LEC apoptosis, to cross-present archived antigens to circulating T cells.

Migratory dendritic cells acquire and present lymphatic endothelial cell-archived antigens during lymph node contraction.

Lymph node (LN) expansion during an immune response is a complex process that involves the relaxation of the fibroblastic network, germinal center formation, and lymphatic vessel growth. These processes require the stromal cell network of the LN to act deliberately to accommodate the influx of immune cells to the LN. The molecular drivers of these processes are not well understood. Therefore, we asked whether the immediate cytokines type 1 IFN produced during viral infection influence the lymphatic network of the LN in mice. We found that following an IFN-inducing stimulus such as viral infection or polyI:C, programmed cell death ligand 1 (PD-L1) expression is dynamically upregulated on lymphatic endothelial cells (LECs). We found that reception of type 1 IFN by LECs is important for the upregulation of PD-L1 of mouse and human LECs and the inhibition of LEC expansion in the LN. Expression of PD-L1 by LECs is also important for the regulation of LN expansion and contraction after an IFN-inducing stimulus. We demonstrate a direct role for both type 1 IFN and PD-L1 in inhibiting LEC division and in promoting LEC survival. Together, these data reveal a novel mechanism for the coordination of type 1 IFN and PD-L1 in manipulating LEC expansion and survival during an inflammatory immune response.

Jeffrey M. Finlon

Division of Gastroenterology and Hepatology,
Department of Medicine,
Division of Gastroenterology and Hepatology, Department of Medicine

University of Colorado Anschutz Medical Campus, School of Medicine

Digestion of the Murine Liver for a Flow Cytometric Analysis of Lymphatic Endothelial Cells

Jeffrey M. Finlon

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Division of Gastroenterology and Hepatology,Department of Medicine,Division of Gastroenterology and Hepatology, Department of Medicine

University of Colorado Anschutz Medical Campus, School of Medicine

Digestion of the Murine Liver for a Flow Cytometric Analysis of Lymphatic Endothelial Cells

Division of Gastroenterology and Hepatology,
Department of Medicine,
Division of Gastroenterology and Hepatology, Department of Medicine