HMGB-1 induces c-kit+ cell microvascular rolling and adhesion via both toll-like receptor-2 and toll-like receptor-4 of endothelial cells.
Bottom Line: In knockout animals, the fraction of rolling cells did not differ significantly from control levels.TLR-2 (-/-) and Tlr4 (LPS-del) stem cells in WT mice did not show significant reduction in rolling and adhesion compared to WT cells.HMGB-1 mediates c-kit(+) cell recruitment via endothelial TLR-2 and TLR-4.
Affiliation: Reference and Translation Centre for Cardiac Stem Cell Therapy, Department of Cardiac Surgery, University Rostock, Rostock, Germany.Show MeSH
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Mentions: Given the potential role of HMGB-1 as mediator of inflammatory response, we carefully evaluated the feasible dosage of the chemokine (dose/response test) by intravital fluorescence microscopy (data not shown). After choosing the favourable amount of protein (400 ng/ml), the expression of crucial markers of inflammation such as β1-integrin and leukocyte common marker CD45 was assessed by real-time PCR. HMGB-1 superfusion induced a moderate increase in EL adhesion (Fig. 5A). However, the levels of β1-integrin and CD45 mRNAs did not change significantly in response to HMGB-1 signal (Fig. 5B). In ‘TLR-2ko’ group, expression levels of the two analysed mRNAs were significantly reduced (Fig. 5B).
Affiliation: Reference and Translation Centre for Cardiac Stem Cell Therapy, Department of Cardiac Surgery, University Rostock, Rostock, Germany.