Treatment Failure in Neovascular Age-Related Macular Degeneration is Associated with a Complex Chemokine Receptor Profile

Objective To investigate if chemokine expression patterns on leucocyte subsets influence the short-term anatomical treatment response of intravitreal antivascular endothelial growth factor therapy against neovascular age-related macular degeneration (AMD). Methods and analysis This study was conducted as a prospective observational cohort study of 79 patients with neovascular AMD. We used optical coherence tomography to quantify central retinal thickness (CRT) and to evaluate the presence of intraretinal and subretinal fluids in treatment-naive patients at baseline and after loading dose. Anatomical response was categorised into either good responders (complete regression of fluid or a reduction of >75% in CRT), partial responders (reduction of 0%-75% in CRT) or non-responders (increase of CRT). Expression levels of chemokine receptors (CCR1, CCR2, CCR3, CCR5, CXCR3 and CX3CR1) were measured on leucocyte subsets (monocytes, CD4 +T cells, and CD8 +T cells) using flow cytometry. Finally, we explored potential correlation patterns of chemokine expression between the leucocyte subsets using group-specific correlation networks. Results Non-responders had higher CCR1 expression on monocytes (p=0.016) and lower CCR3 expression on CD8+ T cells (p=0.037). Correlation network analyses of chemokine receptor expression patterns on leucocyte subsets revealed intergroup differences. Conclusion Short-term anatomical treatment response in neovascular AMD varies according to the leucocyte subset chemokine expression pattern, which confirms that immune dysfunction is a complex issue in AMD. Our results suggest that focusing on chemokines may be a relevant approach towards personalised treatment in neovascular AMD.