Session Title: Free Paper Session 3: AMD I
Session Date/Time: Thursday 07/09/2017 | 08:30-10:00
Paper Time: 09:00
Venue: Room 118
First Author: : M.Nielsen DENMARK
Co Author(s): : Y. Subhi C. Molbech A. Singh M. Nissen T. Sorensen
The purpose of this study was to describe the possible immunological alterations in patients with late stage non-neovascular agerelated macular degeneration, compared to age-matched healthy individuals and patients with neovascular AMD. We, and others, have previously shown an altered distribution of monocytes in patients with neo-vascular AMD, which is morphologically characterized by angiogenesis. However, monocyte distribution in geographic atrophy, which is characterized by cell loss and degeneration, has not been described before.
The project was performed in a clinical department as a prospective case-control study.
A total of 46 patients with geographic atrophy secondary to AMD. Patients were excluded if they had a history of immune dysfunctions, cancer or if they were receiving immune modulating medicine. All patients were interviewed and detailed examinations were performed, including fundoscopy, spectral domain optical coherence tomography, fundus autofluorescence imaging. Fluorescein angiography were performed when suspected choroidal neovascularization. As control groups, 41 patients with neovascular AMD was included, as well as 21 healthy controls. The control groups were matched according to age, smoking habits, body mass index, excersice habits, and comorbidity. Venous blood was obtained, stained with monoclonal antibodies and analyzed using flow cytometry within 4 hours of phlebotomy.
Patients with geographic atrophy showed a significant higher portion of classical monocytes (CD14++CD16-) compared to both control groups (p-value 0.025). In addition, we found a significant higher occurrence of intermediate monocytes (CD14++CD16+) in patients with neovascular AMD (p-value 0.009). Subsequently we found that healthy controls had the highest share of non-classical monocytes (CD14+CD16++) (p-value 0.023).
Our findings show that peripheral monocyte distribution is distinct, compared to neovascular AMD and in healthy controls. The intermediate monocyte population has a comparatively high expression of surface receptors involved in reparative processes, including vascular endothelial growth factor type 1 and 2. After stimulation, the intermediate monocyte produce high amounts of pro-inflammatory cytokines. All of which correlates very well with the highly inflammatory process in neovascular AMD. The non-classical monocyte, which is found to be higher in healthy individuals, is known to be a patrolling monocyte. There seems to be a developmental relationship between these cells (from classical by intermediates to non-classical). This could be caused by a higher consumption or decay of these monocytes, since a larger amount of the classical monocytes are present in the patients with geographic atrophy.