Abstract
Purpose :
Autologous blood-derived eye drops (ABDE) effectively treat ocular surface diseases, but cost and accessibility are barriers in treatment. Isolation of ABDE via polymer driven accelerated erythrocyte sedimentation is theoretically possible. We aim to use sedimentation to isolate platelet-enriched ABDE.
Methods :
Biologically inert polymer solutions were mixed with citrate anticoagulated human blood. Erythrocyte sedimentation rate (ESR) was measured using the Westergren method. ESR of the blood-polymer solutions were compared to a saline-blood mixture. Platelet concentration measured from the recovered supernatant was compared to that of saline control, whole blood and centrifuged plasma. Polymer solutions and final concentrations included Dextran 70 (DEX70) at 2 & 3 g/dL, Dextran 150 (DEX150) at 2 & 3 g/dL, Dextran 500 (DEX500) at 1 & 2 g/dL, Polyethylene Glycol 10 (PEG10) at 0.6 g/dL, PEG 35 (PEG35) at 0.35 g/dL, and 1:1 mixture of PEG10 at 0.6 g/dL and PEG35 at 0.35 g/dL.
Results :
Compared to the ESR of the control (15±8.89 mm/hr), DEX500 at 1 g/dL exhibited the greatest increase (160±9.81 mm/hr, p=2e-3), followed by DEX500 at 3 g/dL (149±1.73 mm/hr, p=2e-4), DEX70 at 2 g/dL (143±22.1 mm/hr, p=2e-3), and DEX150 at 2 g/dL (143±8.33 mm/hr, p=3e-3). Compared to the platelet concentration derived from centrifuged plasma (15 k/uL), DEX70 and DEX150 at 2 g/dL exhibited significantly higher concentrations (478±56.3k/uL, p=2e-3), (472±30.6 k/uL, p=7e-4). Similarly, compared to whole blood (170 k/uL), DEX70 at 2 g/dL and DEX150 at 2 g/dL achieved significantly higher platelet concentrations (p=4e-2 and p=1e-2, respectively).
Conclusions :
Blood mixed with DEX70 at 2 g/dL and DEX150 at 2 g/dL achieved a 10-fold increase in ESR when compared to saline control, and both yielded a 30-fold increase in platelet concentration when compared to centrifuged plasma. In summary, erythrocyte sedimentation using dextran produces platelet-enriched ABDE rapidly, without requiring costly laboratory processing.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.