Junior Group Angiogenesis
These research projects deal with the analysis of physiological and pathological angiogenesis (= new blood vessel formation), e.g. in tumors or in proliferative retinopathy. We are particularly interested in molecular processes in the endothelium and the influence of inflammatory cells on the modulation of blood vessels formation.
Fig. 1: Mouse aortic ring stained for Isolectin GS-IB4 to visualize the angiogenic sprouts (left). PAS-stained retinal cross section of the mouse with pathological vessels in the OIR-Model (middle). Mouse retina at postnatal day 6 stained with Isolectin GS-IB4 to visualize the retinal vessels (right).
In addition to the standard molecular biological methods (e.g. qPCR, Sequencing, Western Blot, Elisa, FACS, IF, IHC), the angiogenic mechanisms are examined using the following models:
- in vitro: e.g.: isolation and culture of primary cells from the mouse (microglia, macrophages and endothelial cells); Co-cultures (cell adhesion and transmigration assays), endothelial cell sprouting experiments
- ex-vivo: aortic ring and coroid sprouting angiogenesis experiments (Fig. 1 left)
- in vivo: physiological angiogenesis in the mouse retina (Fig. 1 right), murine oxygen-induced retinopathy model (OIR model, Fig. 1 middle) and syngeneic tumors in mice
Selected Publications:
Klotzsche-von Ameln A, Sprott D, Harnessing retinal phagocytes to combat pathological neovascularization in ischemic retinopathies? Pflugers Arch. 2022 Jun; 474(6):575-590. doi: 10.1007/s00424-022-02695-7. PMID: 35524802
Korovina I, Neuwirth A, Sprott D, Troullinaki M, Poitz DM, Deussen A, Klotzsche-von Ameln A. Myeloid SOCS3 Deficiency Regulates Angiogenesis via Enhanced Apoptotic Endothelial Cell Engulfment. J Innate Immun. 2019 Oct 1:1-9. doi: 10.1159/000502645. PMID: 31574508
Sprott D, Poitz DM, Korovina I, Ziogas A, Phieler J, Chatzigeorgiou A, Mitroulis I, Deussen A, Chavakis T, Klotzsche-von Ameln A. Endothelial-Specific Deficiency of ATG5 (Autophagy Protein 5) Attenuates Ischemia-Related Angiogenesis. Arterioscler Thromb Vasc Biol. 2019 Jun;39(6):1137-1148. doi: 10.1161/ATVBAHA.119.309973. PMID: 31070476
Korovina I, Neuwirth A, Sprott D, Weber S, Sardar Pasha SPB, Gercken B, Breier G, El-Armouche A, Deussen A, Karl MO, Wielockx B, Chavakis T, Klotzsche-von Ameln A. Hematopoietic hypoxia-inducible factor 2α deficiency ameliorates pathological retinal neovascularization via modulation of endothelial cell apoptosis. FASEB J. 2019 Feb;33(2):1758-1770. doi: 10.1096/fj.201800430R. PMID: 30156910
Klotzsche - von Ameln A, Cremer S, Hoffmann J, Schuster P, Khedr S, Korovina I, Troulinaki M, Neuwirth A, Sprott D, Chatzigeorgiou A, Economopoulou M, Orlandi A, Hain A, Zeiher AM, Deussen A, Hajishengallis G, Dimmeler S, Chavakis T, Emmanouil Chavakis. Endogenous developmental endothelial locus-1 limits ischemia-related angiogenesis by blocking inflammation. Thromb Haemost. 2017 Jun 2;117(6):1150-1163. doi: 10.1160/TH16-05-0354. PMID: 28447099
Klotzsche-von Ameln A, Muschter A, Mamlouk S, Kalucka J, Prade I, Franke K, Rezaei M, Poitz DM, Breier G, Wielockx B. Inhibition of HIF prolyl hydroxylase-2 blocks tumor growth in mice through the antiproliferative activity of TGFβ. Cancer Res. 2011 May 1;71(9):3306-16. doi: 10.1158/0008-5472.CAN-10-3838. PubMed PMID: 21436457.