February 2020 - Barbara Thaler

Barbara Thaler, MSc

MedUni Wien RESEARCHER OF THE MONTH February 2020

Differential expression of Plg-RKT and its effects on migration of proinflammatory monocyte and macrophage subsets

Membrane-bound plasmin is used by immune cells to degrade extracellular matrices, which facilitates migration. The plasminogen receptor Plg-RKT is expressed by immune cells, including monocytes and macrophages. Among monocytes and macrophages, distinct subsets can be distinguished based on cell surface markers and pathophysiological function. Proinflammatory human monocytes and Ly6Chigh mouse monocytes expressed the highest levels of Plg-RKT and bound significantly more plasminogen compared with the other respective subsets. Proinflammatory human macrophages, showed significantly higher expression of Plg-RKT compared with alternatively activated macrophages. Migration of proinflammatory monocytes was plasmin dependent. In an in vivo mouse model, significantly less Ly6Chigh monocyte recruitment was observed in mice deficient of Plg-RKT mice compared with wild-type mice. The data demonstrate higher expression of Plg-RKT on proinflammatory monocyte and macrophage subsets that impacts their migratory capacity.

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