BACKGROUND: Pericytes (PCs) have a synergistic relationship with endothelial cells (MVEC) in regulating capillary permeability. PCs express Toll-like receptor-4 (TLR-4). We hypothesize one mechanism of MVEC/PC co-culture permeability is regulated through lipopolysaccharide (LPS) activation of pericyte TLR-4. METHODS: Rat PCs were harvested and cultured. PCs were transfected with siRNA targeted to TLR-4. Western blotting was used to confirm gene silencing of TLR-4. A previously described co-culture permeability assay was performed after LPS treatment. RESULTS: Western blot confirmed successful silencing of TLR-4 in PCs, which was sustained for 7 days. A dose- and time-dependent effect of LPS on albumin clearance was seen in MVEC/PC co-cultures. Co-cultures with TLR-4 silenced in PCs eliminated the LPS dose-dependent increase in albumin clearance. CONCLUSIONS: TLR-4 regulates pericyte mediated capillary leak seen with LPS exposure. Our TLR-4 silencing model can be used to further investigate TLR-4's role in pericyte mediated capillary leak.
BACKGROUND: Pericytes (PCs) have a synergistic relationship with endothelial cells (MVEC) in regulating capillary permeability. PCs express Toll-like receptor-4 (TLR-4). We hypothesize one mechanism of MVEC/PC co-culture permeability is regulated through lipopolysaccharide (LPS) activation of pericyte TLR-4. METHODS:Rat PCs were harvested and cultured. PCs were transfected with siRNA targeted to TLR-4. Western blotting was used to confirm gene silencing of TLR-4. A previously described co-culture permeability assay was performed after LPS treatment. RESULTS: Western blot confirmed successful silencing of TLR-4 in PCs, which was sustained for 7 days. A dose- and time-dependent effect of LPS on albumin clearance was seen in MVEC/PC co-cultures. Co-cultures with TLR-4 silenced in PCs eliminated the LPS dose-dependent increase in albumin clearance. CONCLUSIONS:TLR-4 regulates pericyte mediated capillary leak seen with LPS exposure. Our TLR-4 silencing model can be used to further investigate TLR-4's role in pericyte mediated capillary leak.
Authors: Konstantin Stark; Annekathrin Eckart; Selgai Haidari; Anca Tirniceriu; Michael Lorenz; Marie-Luise von Brühl; Florian Gärtner; Alexander Georg Khandoga; Kyle R Legate; Robert Pless; Ingrid Hepper; Kirsten Lauber; Barbara Walzog; Steffen Massberg Journal: Nat Immunol Date: 2012-11-25 Impact factor: 25.606
Authors: Irene Guijarro-Muñoz; Marta Compte; Ana Álvarez-Cienfuegos; Luis Álvarez-Vallina; Laura Sanz Journal: J Biol Chem Date: 2013-12-04 Impact factor: 5.157
Authors: Andrea Rachelle C Santos; Galina Dvoriantchikova; Yiwen Li; Ghulam Mohammad; Ahmed M Abu El-Asrar; Rong Wen; Dmitry Ivanov Journal: PLoS One Date: 2014-01-31 Impact factor: 3.240