Interferon alfa induces leukocyte capillary trapping in rat retinal microcirculation.
BACKGROUND
Interferon alfa has been suggested as a possible treatment for choroidal neovascularization. However, retinal complications following interferon therapy have been reported.


OBJECTIVE
To evaluate the effects of interferon alfa on leukocyte dynamics in the rat retinal microcirculation.


METHODS
Interferon alfa of different doses was intravenously administered in rats. Leukocyte dynamics were observed with acridine orange digital fluorography, which uses a nuclear fluorescent dye of acridine orange and scanning laser ophthalmoscopy. This technique allows visualization of leukocyte movements in the retinal microcirculation in vivo.


RESULTS
After interferon alfa was administered, leukocytes adhered to vascular walls and became trapped in the retinal microcirculation. Leukocyte trapping was dose-dependent.


CONCLUSIONS
Interferon alfa increased leukocyte adherence to vascular endothelium and subsequent leukocyte trapping in the retinal capillaries. Interferon alfa may activate leukocytes, and activated leukocytes may be involved in the pathogenesis of microinfarction associated with interferon-induced retinopathy.
Nishiwaki
H
H
Department of Ophthalmology, Faculty of Medicine, Kyoto University, Japan.
Ogura
Y
Y
Miyamoto
K
K
Matsuda
N
N
Honda
Y
Y
D000165:Acridine Orange / Q000008:administration & dosage; D000818:Animals; D001783:Blood Flow Velocity; D002196:Capillaries / Q000166:cytology; D002448:Cell Adhesion / Q000187:drug effects*; D002465:Cell Movement; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D005451:Fluorescein Angiography; D005456:Fluorescent Dyes / Q000008:administration & dosage; D007091:Image Processing, Computer-Assisted; D007275:Injections, Intravenous; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000494:pharmacology*; D007958:Leukocyte Count; D007962:Leukocytes / Q000166:cytology / Q000378:metabolism*; D008833:Microcirculation; D051381:Rats; D011994:Recombinant Proteins; D012171:Retinal Vessels / Q000378:metabolism*
D005456:Fluorescent Dyes; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D000165:Acridine Orange