gms | German Medical Science

VI. International Symposium on AMD – Age-Related Macular Degeneration – Emerging Concepts – Exploring known and Identifying new Pathways

11. - 12.09.2015, Baden-Baden

Role of PlGF in CNV

Meeting Abstract

  • Nadine Reichhart - Berlin
  • S. Crespo-Garcia - Berlin
  • N. Kociok - Berlin
  • A.M. Joussen - Berlin
  • O. Strauß - Berlin

VI. International Symposium on AMD – Age-Related Macular Degeneration – Emerging Concepts – Exploring known and Identifying new Pathways. Baden-Baden, 11.-12.09.2015. Düsseldorf: German Medical Science GMS Publishing House; 2015. Doc15amd42

doi: 10.3205/15amd42, urn:nbn:de:0183-15amd429

Veröffentlicht: 1. Oktober 2015

© 2015 Reichhart et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe



Loss of vision in AMD is mainly due to the development of choroidal neovascularization (CNV), which is partly driven by macrophages and microglia that both carry VEGFR1 (flt-1) receptors specific for VEGF-A and PlGF. A switch from a pure anti- VEGF-A to an anti-PLGF+VEGF-A treatment is beneficial for some patients. We hypothesize a regulation of microglia activity in the retina by PlGF that contributes to the pathophysiology of CNV. We used the model of laser-induced CNV in MacGreen (Csf1r-EGFP) mice, creating 5 laser spots around the optic nerve (argon laser, 120mW, 50µm, 100ms). Microglia was visualized in vivo by scanning laser ophthalmoscope autofluorescence (AF) and ex vivo by using Iba-1. Differential expression of several angiogenic factors and macrophage markers was analyzed 1h and 1, 4 and 10 days after laser by qPCR. Protein expression of PlGF and VEGF-A was detected both in sagittal sections and in whole-mounts of the retina. We found a substantial up-regulation of PlGF mRNA expression at D1 that decreased back to normal levels at D4. However, VEGF-A expression did not increase during the early phase (D1) and even decreased at D4. sFlt-1 mRNA expression showed an instant increase 1h after laser. At D14, in sagittal sections or retina whole-mounts, we observed that up-regulation of VEGF-A expression in response to laser impact is limited to the scar area, while PlGF shows a more homogenous distribution. Additionally, comparable to PlGF expression, activated microglia cells were also present in distant areas from the laser-spots. Among macrophages, we found an increase of M1 (pro-inflammatory) markers (CD68 and CD86) until D4 whereas the M2 marker IL4R did not show significant changes. Thus we show first hints that a combined action of PlGF and microglia plays an important role in the initial phase of CNV after laser.