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Kołodziej, T.

Publications and source records attributed to Kołodziej, T..

2 recordsLinked to original sources

Ectosome effect on endothelial monolayers in hyperglycemic and normoglycemic conditions

Extracellular vesicles, namely those larger ones - Ectosomes (Ect), are thought to be important cell-to-cell communication medium. Ect are considered as a potential therapeutic for type-1 and type-2 diabetes mellitus. Ect can be internalized by endothelial cells and, owing to their cargo, they modulate targeted cell behavior. Under hyperglycemic conditions (HGC), endothelial cells changed their properties and became stiffer and less mobile which causes endothelial dysfunction and abnormalities in micro- and macrovascular systems. The aim of this study was to find whether Ect restore mobility and motility of macrovascular endothelial cells under HGC. Uptake of Ect, cell morphology, cytoskeleton organization and membrane stiffness (by atomic force microscopy) were analyzed after the exposure to isolated Ect. To find which cellular pathways were deregulated by HGC and whether Ect could potentially restore gene expression profile, transcriptome analysis was done. We observed that endothelial cells internalized more Ect under normoglycemic conditions (NGC) then HGC. Hyperglycemic cells (HG) were bigger and showed the stiffer surface with denser actin cytoskeleton in comparison to normoglycemic cells. Number of metabolic pathways was influenced under HGC, especially those related to intracellular transport, metabolism and cellular component organization and Ect did not restore HGC impaired cell signaling. Ectosomes cannot reverse this harmful effect of hyperglycemia in endothelial cells, which can have clinical implication in use Ect as therapeutic target in diabetes treatment.

cell biology↗

RHOA mediated mechanical force generation through Dectin-1

Dectin-1 is an innate immune pattern recognition receptor which recognizes {beta}-glucan on the Candida albicans (C. albicans) cell wall. Recognition of {beta}-glucan by immune cells leads to phagocytosis, oxidative burst, cytokine and chemokine production. We looked for specific mechanisms that coordinate phagocytosis downstream of Dectin-1 leading to actin reorganization and internalization of fungus. We found that stimulation of Dectin-1 by soluble {beta}-glucan leads to mechanical force generation and areal contraction in Dectin-1 transfected HEK-293 cells and M1 macrophages. With inhibitor studies, we found this force generation is a SYK-independent, SFK (SRC Family Kinase)-dependent process mediated through the RHOA-ROCK-MLC pathway. We confirmed activation of RHOA downstream of Dectin-1 using G-LISA and stress fiber formation. Through phagocytosis assays, we found direct evidence for importance of RHOA-ROCK-MLC pathway in process of phagocytosis of C. albicans. In conclusion, we found evidence for RHOA-ROCK-MLC mediated mechanical force generation downstream of Dectin-1 for C. albicans phagocytosis.

immunology↗