Macrophage-like Cells Are Increased in Patients with Vision-Threatening Diabetic Retinopathy and Correlate with Macular Edema

Abstract

Macrophage-like cells (MLCs) are potential inflammatory biomarkers. We previously showed that MLCs are increased in proliferative diabetic retinopathy (PDR) eyes. Vision-threatening diabetic retinopathy (VTDR) includes PDR, severe non-PDR (NPDR), and diabetic macular edema (DME). No prior data exist on MLCs in eyes with severe NPDR or DME. This prospective, cross-sectional optical coherence tomography-angiography (OCT-A) imaging study included 40 eyes of 37 participants who had NPDR classified as non-VTDR (n = 18) or VTDR (n = 22). Repeated OCT-A images were registered, averaged, and used to quantify the main outcome measures: MLC density and percent area. MLC density and percent area were correlated with clinical characteristics, NPDR stage, presence of DME, and OCT central subfield thickness (CST). In VTDR eyes, MLC density (2.6-fold, p < 0.001) and MLC percent area (2.5-fold, p < 0.01) were increased compared with non-VTDR eyes. Multiple linear regression analysis between MLC metrics and clinical characteristics found that MLC density was positively correlated with worse NPDR severity (p = 0.023) and higher CST values (p = 0.010), while MLC percent area was only positively associated with increased CST values (p = 0.006). MLCs are increased in patients with VTDR. Macular edema is the most strongly associated factor with increased MLC numbers in NPDR eyes.

Vitreoretinal Interface Cells Correlate In Vivo With Uveitis Activity and Decrease With Anti-Inflammatory Treatment

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PET Imaging for The Early Evaluation of Ocular Inflammation in Diabetic Rats by Using [ 18 F]-DPA-714

“…Some studies have used OCT to visualize in vivo macrophage-like cells (MLCs), which is thought to be microglia or hyalocytes, located at the vitreoretinal interface. OCT found MLC showed increased density, nonuniform distribution and altered morphology in eyes of patients with proliferative diabetic retinopathy (PDR) (Corsi and Zhang and Nesper. 2022).…”

Macrophage/microglia polarization for the treatment of diabetic retinopathy

“…Thus, activated microglia are tightly associated with blood vessels that are closely connected geographically and promote microangiopathy in DR. Microglia/macrophages accumulate in the retina under the prolonged effects of hyperglycemia, indicating their contribution to the development of the disease. Optical coherence tomography angiography revealed that patients with PDR had significantly more macrophage-like cells surrounding their retinal vessels than healthy individuals, diabetics without DR, and patients with NPDR ( 96 ); diabetic macular edema was the most relevant factor contributing to the increase in macrophage-like cells ( 97 ). Moreover, macrophages near the vitreoretinal interface, mainly microglia, may act as biomarkers for inflammation ( 98 ).…”