Ocular inflammatory effects of intravitreal interleukin 1
J. T. Rosenbaum, J. R. Samples, S. H. Hefeneider and E. L. Howes Jr
Locally injected endotoxin induces potent inflammatory changes in the
rabbit eye. To clarify the possible role of interleukin 1 (Il-1), an
endotoxin-induced monokine, in rabbit eye inflammation, we injected rabbits
with recombinant Il-1 (rIl-1). Twelve and a half to 200 U of intravitreally
injected rIl-1 consistently induced inflammation, which was documented
using slit-lamp biomicroscopy, histologic methods, or direct quantitation
of protein in the aqueous humor. Responses including a cellular infiltrate
in the anterior chamber, protein extravasation, and iris vessel dilatation
became evident within six hours, peaked at 24 hours, and began to recede by
48 to 72 hours after the injection. Pathologic changes primarily occurred
in the anterior chamber and included edema, hemorrhage, and cellular
infiltration. Locally injected corticosteroid reduced but did not prevent
rIl-1-induced changes in vascular permeability. Heat-inactivated rIl-1
induced minimal changes, as determined by histologic methods, slit-lamp
examination, or direct protein measurement. These data support the
conclusion that Il-1 should be considered as a potential mediator of ocular
inflammation.
