Aflibercept Intervention in Experimental Branch Retinal Vein Occlusion Results in Upregulation of DnaJ Homolog Subfamily C Member 17

Abstract

Aflibercept is an inhibitor of vascular endothelial growth factor (VEGF) used to treat macular edema following branch retinal vein occlusion (BRVO). Despite well-documented efficacy, there is limited knowledge about proteome changes following aflibercept intervention in BRVO. Proteome changes may provide insights into mechanisms of action as well as aspects related to safety profile. In seven Danish Landrace pigs, BRVO was induced with a well-established experimental model of argon laser-induced BRVO. BRVO was induced in both eyes. Three days after the induced BRVO, aflibercept was injected intravitreally in the right eyes, while the left eyes received intravitreal isotonic saline water. Retinas were collected 15 days after the induced BRVO and analyzed with label-free quantification liquid chromatography tandem mass spectrometry (LFQ LC-MS/MS). Fourteen proteins were changed in expression following aflibercept intervention in the BRVO model. LFQ LC-MS/MS identified an upregulation of DnaJ homolog subfamily C member 17 (DNAJC17) (fold change = 6.19) and a modest downregulation of isoform 2 of the protein encoded by N-myc downstream regulated gene 2 (NDRG2) (fold change = 0.40). NDRG2 was unchanged by Western blotting. In the additional significantly regulated proteins, only discrete changes were observed (fold changes 0.52–1.59). Our study is the first to report an association between aflibercept intervention and the heat shock protein DNAJC17. Our results indicate that the role of heat shock proteins in the treatment of BRVO should be further explored.

Proteome Analysis of Aflibercept Intervention in Experimental Central Retinal Vein Occlusion

“…It consists of a constant Fc domain of human immunoglobulin G1 fused with the second immunoglobulin domain of VEGF receptor-1 (VEGFR-1) and the third immunoglobulin domain of VEGF receptor-2 (VEGFR-2) [ 8 , 9 ]. Although aflibercept treatment has become the standard of care, retinal large-scale protein changes following aflibercept intervention in CRVO remain largely unstudied [ 10 , 11 ].…”

“…Furthermore, studying retinal proteome changes with proteomic techniques may bring insights into the safety profile of aflibercept. Elucidating the retinal proteome in CRVO following aflibercept intervention may also provide a potential for discoveries that can lead to the improvement of existing therapies [ 10 , 11 ].…”

Laser-Induced Porcine Model of Experimental Retinal Vein Occlusion: An Optimized Reproducible Approach

“…After filtration, a different number of proteins were successfully identified and quantified in each of the reports, as follows: 1932 proteins with 14 proteins significantly regulated with label-free quantification [ 25 ], 3559 proteins with 21 proteins significantly regulated with TMT labeling [ 26 ], 2749 proteins with 5 proteins significantly regulated with TMT labeling [ 28 ], 4013 proteins with 9 proteins significantly regulated with TMT labeling [ 29 ], 3716 proteins with 26 proteins significantly regulated with TMT labeling [ 30 ], 1974 proteins with 52 proteins significantly regulated with label-free quantification [ 31 ], 3791 proteins with 147 proteins significantly regulated with TMT labeling [ 32 ], and 2837 proteins with 237 proteins significantly regulated with label-free quantification [ 33 ].…”

“…We reviewed animal studies of experimental RVO performed in our laboratories in a 10-year period [ 25 , 26 , 28 , 29 , 30 , 31 , 32 , 33 ]. A total of 130 eyes from 65 animals were used ( Table 1 ), which included 65 eyes with experimental BRVO from 38 animals and 43 eyes with experimental CRVO from 27 animals.…”

“…The overall objective of proteome studies is to identify and quantify the entire set of proteins in a given cell, tissue, or biofluid to provide insights into the biological processes in the disease or intervention under study [ 16 , 22 , 23 , 24 ]. Studying interventions in experimental RVO may elucidate mechanisms of action which can potentially be used to improve existing therapies [ 25 , 26 ].…”