Cytokines possibly involved in idiopathic epiretinal membrane progression after uncomplicated cataract surgery

Aqueous Humor Cytokines in Idiopathic Epiretinal Membrane: Correlation with Disease Severity

BACKGROUND

To analyze the concentration of aqueous humor (AH) cytokines in eyes with idiopathic epiretinal membrane (iERM) and to investigate their potential correlation with disease severity.

METHODS

Retrospective cross-sectional case-control institutional study. A total of 16 eyes of 16 iERM patients and 14 eyes of 14 age-matched healthy controls were enrolled. AH samples were analyzed for various biomarkers using a glass-chip protein array. Cytokines associated with inflammation, fibrosis, angiogenesis, and glial signal transduction were quantified.

RESULTS

Significant differences in cytokine concentration were observed between the iERM group and controls, with 19 cytokines elevated in the iERM group (among them IL-6, IL-8, PDGF-AB, PDGF-BB, TGFB-1, TGFB-2, TGFB-3, VEGF A, VEGF C, VEGF D, p < 0,05, 95% confidence interval). Correlation analysis revealed associations between cytokine levels and iERM severity. Notably, stages 2, 3, and 4 of iERM demonstrated increased levels of various biomarkers.

CONCLUSIONS

This study provides insights into the complex molecular interactions underlying iERM pathogenesis, describing a correlation between neuroinflammation and iERM severity.

Epiretinal membranes in patients with uveitis: an update on the current state of management

PURPOSE

This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up, and therapeutic approach of uveitic epiretinal membranes (ERM).

METHODS

A thorough investigation of the literature was conducted using the PubMed database. Additionally, a complementary search was carried out on Google Scholar to ensure the inclusion of all relevant items in the collection.

RESULTS

ERM is an abnormal layer at the vitreoretinal interface, resulting from myofibroblastic cell proliferation along the inner surface of the central retina, causing visual impairment. Known by various names, ERM has diverse causes, including idiopathic or secondary factors, with ophthalmic imaging techniques like OCT improving detection. In uveitis, ERM occurrence is common, and surgical intervention involves pars plana vitrectomy with ERM peeling, although debates persist on optimal approaches.

CONCLUSIONS

Histopathological studies and OCT advancements improved ERM understanding, revealing a diverse group of diseases without a unified model. Consensus supports surgery for uveitic ERM in progressive cases, but variability requires careful consideration and effective inflammation management. OCT biomarkers, deep learning, and surgical advances may enhance outcomes, and medical interventions and robotics show promise for early ERM intervention.

Optical coherence tomography biomarkers as outcome predictors to guide dexamethasone implant use in patients with iERM: a randomized controlled trial

BACKGROUND

We aimed to investigate the anatomical features of optical coherence tomography (OCT) and vitreous cytokine levels as predictors of outcomes of combined phacovitrectomy with intravitreal dexamethasone (DEX) implants for idiopathic epiretinal membrane (iERM) treatment.

METHODS

A prospective, single-masked, randomized, controlled clinical trial included 48 eyes. They were randomly assigned in a 1:1 ratio to undergo the DEX group (combined phacovitrectomy with ERM peeling and Ozurdex implantation) and control group (phacovitrectomy only). Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were assessed at 1 d, 1 week, 1 month, and 3 months. The structural features of OCT before surgery were analysed for stratified analysis. Baseline soluble CD14 (sCD14) and sCD163 levels in the vitreous fluid were measured using ELISA.

RESULTS

BCVA and CMT were not significantly different in the DEX and control groups. Eyes with hyperreflective foci (HRF) at baseline achieved better BCVA (Ptime*group=0.746; Pgroup=0.043, Wald χ²=7.869) and lower CMT (Ptime*group = 0.079; Pgroup = 0.001, Wald χ²=6.774) responses to DEX during follow-up. In all patients, the mean vitreous level of sCD163 in eyes with HRF was significantly higher than that in eyes without HRF (P = 0.036, Z=-2.093) at baseline. In the DEX group, higher sCD163 predicted greater reduction in CMT from baseline to 1 month (r = 0.470, P = 0.049).

CONCLUSIONS

We found that intraoperative DEX implantation did not have beneficial effects on BCVA and CMT over a 3-month period in all patients with iERM, implying that the use of DEX for all iERM is not recommended. In contrast, for those with HRF on OCT responded better to DEX implants at the 3-month follow-up and thier vitreous fluid expressed higher levels of sCD163 at baseline. These data support the hypothesis that DEX implants may be particularly effective in treating cases where ERM is secondary to inflammation.

TRIAL REGISTRATION

The trail has been registered at Chinese Clinical Trail Registry( https://www.chictr.org.cn ) on 2021/03/12 (ChiCTR2100044228). And all patients in the article were enrolled after registration.

Long-Term Intraocular Pressure Fluctuation and Epiretinal Membrane in Patients with Glaucoma or Glaucoma Suspect

Background: A relationship between glaucoma and epiretinal membrane (ERM) has been suggested previously. We investigated the association between intraocular pressure (IOP) fluctuation and idiopathic ERM in patients with glaucoma or glaucoma suspect. Methods: Among patients with glaucoma or glaucoma suspect, data from 43 patients with ERM and 41 patients without ERM were reviewed and analyzed in this retrospective study. The long-term fluctuation of IOP was defined based on the standard deviation of IOP across all visits. Results: Patients with ERM were older and had a higher SD of IOP and a higher proportion of having a history of cataract surgery and greater macular thickness (p = 0.018, 0.049, 0.013, and <0.001, respectively). In multiple logistic regression analysis, the high-IOP-fluctuation group was associated with the presence of ERM (p = 0.047). Among patients with ERM, eyes with stage-3 or -4 ERM had worse visual field defects based on mean deviation than those with stage-1 or -2 ERM (p = 0.025). Conclusions: Long-term IOP fluctuation was associated with idiopathic ERM in patients with glaucoma or glaucoma suspect. Idiopathic ERM could serve as a biomarker for long-term IOP fluctuation in glaucoma patients, particularly in clinics where measuring long-term IOP fluctuation during the first visit is not feasible due to its time-consuming nature.

Pro-Fibrotic Role of Interleukin-4 in Influencing Idiopathic Epiretinal Membrane in Cataract Patients: Analysis From Clinical-Experimental Approaches

Purpose

To evaluate the role of interleukin-4 in influencing idiopathic epiretinal membrane (iERM) formation and early progression post cataract surgery (PCS) from clinical and experimental perspectives.

Methods

We quantified levels of IL-4 in aqueous humor (AH) samples from 22 iERM patients and 31 control subjects collected before and 20 hours after cataract surgeries using ELISA. After a 3-month follow-up, the association between IL-4 levels and iERM progression measurements was identified. In addition, in vitro studies were conducted to investigate the effects of IL-4 on primary rat retinal Müller glia proliferation, migration, and glial-mesenchymal transition (GMT).

Results

Concentrations of IL-4 were significantly higher in preoperative AH samples from iERM patients versus controls (P = 0.006). Postoperatively, although IL-4 levels were elevated in both groups compared to their respective preoperative levels, they were even more obviously so in the iERM group (P < 0.001). Multivariate linear regression analyses revealed that, postoperatively, IL-4 level elevation was positively associated with macular volume and thickness increase (both P < 0.05) in iERM patients. However, no correlations were observed between IL-4 level (changes) and clinical characters in the controls. In vitro studies demonstrated that IL-4 promoted Müller glia proliferation and migration and increased the expression of GMT-related markers in a manner independent of transforming growth factor-β1 (TGF-β1).

Conclusions

IL-4 plays a crucial pro-fibrotic role in iERM formation and early progression 3 months PCS possibly by stimulating Müller glia proliferation, migration, and GMT in a TGF-β1-independent manner.

Translational Relevance

The current study suggests the potential of IL-4 as a novel therapeutic target for iERM.

The Immediate Early Response of Lens Epithelial Cells to Lens Injury

Cataracts are treated by lens fiber cell removal followed by intraocular lens (IOL) implantation into the lens capsule. While effective, this procedure leaves behind numerous lens epithelial cells (LECs) which undergo a wound healing response that frequently leads to posterior capsular opacification (PCO). In order to elucidate the acute response of LECs to lens fiber cell removal which models cataract surgery (post cataract surgery, PCS), RNA-seq was conducted on LECs derived from wild type mice at 0 and 6 h PCS. This analysis found that LECs upregulate the expression of numerous proinflammatory cytokines and profibrotic regulators by 6 h PCS suggesting rapid priming of pathways leading to inflammation and fibrosis PCS. LECs also highly upregulate the expression of numerous immediate early transcription factors (IETFs) by 6 h PCS and immunolocalization found elevated levels of these proteins by 3 h PCS, and this was preceded by the phosphorylation of ERK1/2 in injured LECs. Egr1 and FosB were among the highest expressed of these factors and qRT-PCR revealed that they also upregulate in explanted mouse lens epithelia suggesting potential roles in the LEC injury response. Analysis of lenses lacking either Egr1 or FosB revealed that both genes may regulate a portion of the acute LEC injury response, although neither gene was essential for expression of either proinflammatory or fibrotic markers at later times PCS suggesting that IETFs may work in concert to mediate the LEC injury response following cataract surgery.