Abstract
Purpose: Diabetic retinopathy (DR) is a major microvascular complication of type
2 diabetes mellitus (T2DM). Myelomonocytic proangiogenic cells (PAC) have
been implicated in DR pathogenesis, but their functional and developmental
abnormalities are unclear. In this study we assessed PAC characteristics from
healthy controls, T2DM patients with DR (DR) and without (NoDR) in order to
determine the consequence of the diabetic condition on PAC phenotype and
function, and whether these differ between DR and NoDR patients.
Methods: PAC were generated by culturing PBMC on fibronectin coating and
then immunophenotyped using flow cytometry. Furthermore, cells were sorted
based on CD14, CD105, and CD133 expression and added to an in vitro 3-D
endothelial tubule formation assay, containing GFP-expressing human retinal
endothelial cells (REC), pericytes, and pro-angiogenic growth factors. Tubule
formation was quantified by fluorescence microscopy and image analysis.
Moreover, sorted populations were analyzed for angiogenic mediator production using a multiplex assay.
Results: The expression of CD16, CD105 and CD31, but not CD133, was lower in
PAC from T2DM patients with or without DR. Myeloid and non-myeloid T2DM-derived sorted populations increased REC angiogenesis in vitro as compared to control cultures. They also showed increased S100A8 secretion, decreased VEGF-A secretion, and similar levels of IL-8, HGF, and IL-3 as compared to healthy control (HC)-derived cell populations.
Conclusion: T2DM PAC are phenotypically and functionally altered compared to
PAC from HC. Differences between DR and NoDR PAC are limited. We propose
that impaired T2DM PAC provide inadequate vascular support and promote
compensatory, albeit pathological, retinal neovascularization.
2 diabetes mellitus (T2DM). Myelomonocytic proangiogenic cells (PAC) have
been implicated in DR pathogenesis, but their functional and developmental
abnormalities are unclear. In this study we assessed PAC characteristics from
healthy controls, T2DM patients with DR (DR) and without (NoDR) in order to
determine the consequence of the diabetic condition on PAC phenotype and
function, and whether these differ between DR and NoDR patients.
Methods: PAC were generated by culturing PBMC on fibronectin coating and
then immunophenotyped using flow cytometry. Furthermore, cells were sorted
based on CD14, CD105, and CD133 expression and added to an in vitro 3-D
endothelial tubule formation assay, containing GFP-expressing human retinal
endothelial cells (REC), pericytes, and pro-angiogenic growth factors. Tubule
formation was quantified by fluorescence microscopy and image analysis.
Moreover, sorted populations were analyzed for angiogenic mediator production using a multiplex assay.
Results: The expression of CD16, CD105 and CD31, but not CD133, was lower in
PAC from T2DM patients with or without DR. Myeloid and non-myeloid T2DM-derived sorted populations increased REC angiogenesis in vitro as compared to control cultures. They also showed increased S100A8 secretion, decreased VEGF-A secretion, and similar levels of IL-8, HGF, and IL-3 as compared to healthy control (HC)-derived cell populations.
Conclusion: T2DM PAC are phenotypically and functionally altered compared to
PAC from HC. Differences between DR and NoDR PAC are limited. We propose
that impaired T2DM PAC provide inadequate vascular support and promote
compensatory, albeit pathological, retinal neovascularization.
| Original language | English |
|---|---|
| Number of pages | 9 |
| Journal | Frontiers in Ophthalmology |
| Volume | 3 |
| DOIs | |
| Publication status | Published - 23 Mar 2023 |
Keywords
- diabetic retinopathy
- myeloid-derived pro-angiogenic cells
- retinal endothelial cells
- in vitro angiogenesis
- microvascular dysfunction