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Biomedicine Seminar

Markus Sperandio from LMU Munich, Germany, will present the work of his research group. The title of his talk is “Neutrophil recruitment: from rolling to extravasation - from the fetus to the adult ”.

13.12.2018 | Zitta Glattrup Nygaard

Dato tor 20 dec
Tid 12:00 13:00
Sted The Biochemistry Lecture Hall 6, build. 1170-347

Neutrophil recruitment is an important immunological process which enables the extravasation of circulating neutrophils into tissues. Neutrophil recruitment can already be found during fetal development although at much lower level. The recruitment process is characterized by adhesion and activation events which occur in a cascade-like fashion and includes neutrophil rolling, firm arrest, postarrest modifications and transmigration into tissue. Neutrophil rolling is mediated through binding of selectins to carbohydrate-based moieties on selectin ligands. Rolling along inflamed microvessels is mostly dependent on endothelium-expressed P-selectin and E-selectin interacting with P-selectin glycoprotein ligand-1 (PSGL-1) and other less defined selectin ligands (e.g. CD44, ESL-1). During rolling, neutrophils screen the endothelial surface for activation signals including chemokines, and DAMP and PAMP molecules. Together with selectins, these surface factors trigger the activation of leukocyte-expressed integrins such as beta2 integrins LFA-1 and Mac-1 mediating further slowing down of the rolling leukocyte and eventual firm arrest on the endothelium. Additional signaling events triggered by interactions between leukocyte integrins and their respective ligands on the endothelium then prepare leukocytes for extravasation into tissue. These postarrest modifications include intravascular leukocyte flattening and spreading followed by crawling along the endothelium in search for an appropriate spot for transmigration into tissue. Transmigration per se also proceeds in a cascade-like fashion and involves additional sets of adhesion relevant surface molecules such as PECAM-1, JAM family members or CD99. Transendothelial migration can occur through a para- or transcellular route with a preference of neutrophils for the paracellular route. To fully transmigrate, neutrophils have also to penetrate the basement membrane, which requires intracellular vesicle trafficking for neutrophil elastase release and to guarantee expression of various beta1 integrins on the neutrophil surface. My group investigates all aspects of neutrophil recruitment using several modes of intravital microscopy and various genetic mouse models. In addition, we complement those in vivo studies with dynamic and static functional neutrophil assays. Results from these studies I will present today including our most recent work on Src kinases and on fetal neutrophil recruitment.

For further information you are welcome to contact me at: markus.sperandio@lmu.de

The seminar will be held at 12:00 pm in the Biochemistry Aud 6 – building 1170-347.

The talk will be of 45 minutes duration, followed by 15 minutes of discussion.

Sign-up for a free sandwich  before Tuesday 18 December.

Seminar, Forskning, Ph.d.-studerende, Institut for Biomedicin, Obligatorisk for alle eksterne målgrupper, Institut for Biomedicin, Studerende, Teknisk/administrativ medarbejder, Videnskabelig medarbejder