The role of Robo4 molecule in leukocyte traffic
Brenyah, Heini-Maria (2020-12-11)
The role of Robo4 molecule in leukocyte traffic
(11.12.2020)
Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty.
avoin
Julkaisun pysyvä osoite on:
https://urn.fi/URN:NBN:fi-fe20201222102675
https://urn.fi/URN:NBN:fi-fe20201222102675
Tiivistelmä
Leukocyte traffic is an essential part of the immune system as lymphocytes continuously migrate to lymph nodes in search of foreign antigens. Lymphocytes can access the lymph node either via blood vasculature or afferent lymphatics. A potential molecule in regulating these pathways is the Roundabout Guidance Receptor 4 (Robo4). Robo4 is expressed in blood vessels, the medullary sinus of the lymph nodes and Peyer’s patch (PP) lymphatics. Peyer’s patches are located in the small intestine and merely have efferent lymphatics.
In this study Robo4 knockout (KO) and wild type mouse models were used to investigate the effects of Robo4 on leukocyte migration. A monoclonal Robo4 murine antibody was generated to explore the Robo4 expression and localization with imaging. Furthermore, the function of Robo4 in the leucocyte migration and B cell turnover in Peyer’s patches was examined.
The localization of Robo4 expression was limited specifically to the medullary sinus of the mouse lymph node and lymphatics of the PPs. Robo4 had a small effect on the migration of lymphocytes into the lymphoid tissues via blood vessels in vivo, and it controlled the adhesion between lymphocytes and the medullary sinus in vitro. Moreover, Robo4 contributed specifically to naïve B cell turnover in PPs because the percentage of naïve B cells was increased in the Robo4 KO mice. Interestingly, concomitant increase in PP size or increased apoptosis was not observed as a compensatory mechanism. In conclusion, Robo4 is a new regulator of lymphocyte migration in the lymphoid tissues.
In this study Robo4 knockout (KO) and wild type mouse models were used to investigate the effects of Robo4 on leukocyte migration. A monoclonal Robo4 murine antibody was generated to explore the Robo4 expression and localization with imaging. Furthermore, the function of Robo4 in the leucocyte migration and B cell turnover in Peyer’s patches was examined.
The localization of Robo4 expression was limited specifically to the medullary sinus of the mouse lymph node and lymphatics of the PPs. Robo4 had a small effect on the migration of lymphocytes into the lymphoid tissues via blood vessels in vivo, and it controlled the adhesion between lymphocytes and the medullary sinus in vitro. Moreover, Robo4 contributed specifically to naïve B cell turnover in PPs because the percentage of naïve B cells was increased in the Robo4 KO mice. Interestingly, concomitant increase in PP size or increased apoptosis was not observed as a compensatory mechanism. In conclusion, Robo4 is a new regulator of lymphocyte migration in the lymphoid tissues.