Trans-endothelial migration (TEM) is essential for leukocyte circulation. While much is known about trans-blood endothelial migration, far less is known about trans-lymphatic endothelial migration. We established an in vitro system to evaluate lymphatic TEM for various cell types across primary mouse and human lymphatic endothelial cells (LEC), and validated the model for the murine LEC cell line SVEC4-10. T cells exhibited enhanced unidirectional migration from the basal (abluminal) to the apical (luminal) surface across LEC, whereas for blood endothelial cells (BEC) they migrated similarly in both directions. This preferential, vectorial migration was chemotactic toward many different chemoattractants and dose-dependent. Stromal protein fibers, interstitial type fluid flow, distribution of chemokines in the stromal layer, and inflammatory cytokines influenced LEC phenotype and leukocyte TEM. Activated and memory CD4 T cells, macrophages, and dendritic cell (DC) showed chemoattractantΔdriven vectorial migration, while CD8 T cell migration across LEC was not. The system was further validated for studying cancer cell transmigration across lymphatic endothelium. This model for lymphatic TEM for various migrating and endothelial cell types possesses the capacity to be high-throughput, highly reproducible and integrate the complexities of lymphatic biology, stromal variability, chemoattractant distribution, and fluid flow.
Bibliographical noteFunding Information:
This work was supported by NIH R01AI062765, AI114496 to JSB, Grants from the Maryland Living Legacy Foundation and the American Society of Transplant Surgeons to CCB, R01 HL11879 and RO1 CA72669 to BRB and P01 CA 065493 to BRB and KLH. Flow sorting was performed at the University of Maryland Marlene and Stewart Greenebaum Cancer Center Flow Cytometry Shared Service by Dr. Ferenc Livak and Karen Underwood. We are grateful for technical support from Chelsea Wagner.
© 2017 The Author(s).
Copyright 2017 Elsevier B.V., All rights reserved.