The Presence of Activated CD4+ T Cells Is Essential for the Formation of Colony-Forming Unit-Endothelial Cells by CD14+ Cells

• Published in: The Journal of immunology (1950) Vol. 180; no. 7; pp. 5141 - 5148
• Main Authors: van Beem, Rachel T, Noort, Willy A, Voermans, Carlijn, Kleijer, Marion, ten Brinke, Anja, van Ham, S. Marieke, van der Schoot, C. Ellen, Zwaginga, Jaap Jan
• Format: Journal Article
• Language: English
• Published: United States Am Assoc Immnol 01.04.2008
• Subjects: CD3 Complex - immunology; CD4-Positive T-Lymphocytes - immunology; Cell Communication; Cell Proliferation; Cells, Cultured; Cytokines - biosynthesis; Cytokines - genetics; Cytokines - immunology; Endothelial Cells - immunology; Gene Expression Regulation; Histocompatibility Antigens Class II - immunology; Humans; Intercellular Signaling Peptides and Proteins - genetics; Intercellular Signaling Peptides and Proteins - metabolism; Lipopolysaccharide Receptors - immunology; Monocytes - cytology; Monocytes - immunology; Neovascularization, Physiologic - genetics; Phenotype; Receptors, Antigen, T-Cell - immunology; Stem Cells - immunology
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.180.7.5141

The number of colony forming unit-endothelial cells (CFU-EC) in human peripheral blood was found to be a biological marker for several vascular diseases. In this study, the heterogeneous composition of immune cells in the CFU-ECs was investigated. We confirmed that monocytes are essential for the formation of CFU-ECs. Also, however, CD4(+) T cells were found to be indispensable for the induction of CFU-EC colonies, mainly through cell-cell contact. By blocking or activating CD3 receptors on CD4(+) T cells or blocking MHC class II molecules on monocytes, it was shown that TCR-MHCII interactions are required for induction of CFU-EC colonies. Because the supernatant from preactivated T cells could also induce colony formation from purified monocytes, the T cell support turned out to be cytokine mediated. Gene expression analysis of the endothelial-like colonies formed by CD14(+) cells showed that colony formation is a proangiogenic differentiation and might reflect the ability of monocytes to facilitate vascularization. This in vitro study is the first to reveal the role of TCR-MHC class II interactions between T cells and monocytes and the subsequent inflammatory response as stimulus of monocytic properties that are associated with vascularization.