Abstract
Purpose :
To investigate the concentration of inflammatory cytokines in the aqueous humour of patients across primary angle closure disease spectrum.
Methods :
Aqueous humour samples were obtained during elective phacoemulsification or combined phacoemulsification and trabeculectomy surgeries from 15 cataract (as controls) and 46 angle closure subjects (including 16 primary angle closure suspects (PACS), 16 (PAC) primary angle closure and 14 primary angle closure glaucoma (PACG)). The concentration of the cytokines in the aqueous humour were measured using AYOXXA’s LUNARISTM Human 11-plex Ophthalmology panel which included the following cytokines: PDGF-BB, Ang-2, PIGF, MCP-1, VEGF, CRP, IP-10, CXCL12, CXCL13, IL-8, and IL-6. The samples which were below the lower limits of detection (LOD) were replaced by ½ of the LOD of the particular cytokine. Kruskal-Walis test was used to determine the mean difference in concentrations of the cytokines between the groups.
Results :
The mean age of the subjects was 70.0±6.5 years with no significant difference between the groups (p=0.69). We noted a significant difference in the proportion of measurable cytokines across the angle closure disease spectrum for Ang-2 (26.7% in normals, 31.3% in PACS, 50.0% in PAC and 78.6% in PACG, p=0.02) and CXCL-13 (53.3% in normals, 43.8% in PACS, 62.5% in PAC and 100.0% in PACG, p=0.009). IL-8 was detected in 95.1% (58 out of 61) of samples. The concentration of IL-8, Ang-2 and CXCL-13 were significantly different between the groups (p=0.02, p=0.008 and p=0.01 respectively) being highest in the PACG group, followed by PAC, normals and PACS respectively. There was a significant positive correlation between IL-8 concentration and presenting intraocular (IOP, correlation coefficient [r]=0.34, p=0.01), and with the magnitude of peripheral anterior synechiae (PAS) (r=0.31, p=0.03). Significant positive correlation were also noted between Ang-2 and presenting IOP (r=0.31, p=0.02), and between CXCL-13 and presenting IOP (r=0.28, p=0.04).
Conclusions :
Aqueous concentration of the inflammatory cytokine IL-8, Ang-2 and CXCl-13 were elevated in PACG and significantly correlated with presenting IOP; suggesting that inflammation may play a role in PACG.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.