Abstract
Abstract: :
Purpose: It is well established that elicitation of anterior chamber acquired immune deviation (ACAID) requires antigen uptake by resident ocular antigen presenting cells (APC) that emigrate to the spleen and induce deviant immunity. However the pathway APC use to leave the eye and migrate to the spleen remains uncertain. These studies attempt to determine the route of egress and subsequent migration of antigen presenting cells in the anterior segment of the eye following antigen challenge by in vivo confocal microscopy and in vivo flow cytometery and hypothesize that antigen bearing APC emigrate through venous circulation to impose ACAID. Methods: GFP–positive peritoneal exudates cells (PEC) from FVB.Cg–Tg(GFPU)5Nagy/J mice were harvested 3 days after thioglycolate treatment and incubated with ovalbumin or serum free media alone overnight. PEC were harvested and injected into the AC of BALB/c mice. The eyes were viewed at 1, 3, 6, 24, 48, and 72 hours after injection using in vivo confocal microscopy and followed in the circulation using in vivo flow cytometery and confocal microscopy. The spleen and submandibular/cervical lymph nodes of the PEC challenged mice were removed and examined for presence of GFP positive cells. At 72 hours the eyes of these mice were enucleated, embedded in OCT, frozen, sectioned and viewed by confocal microscopy. Results: GFP+ PECs are seen in the anterior chamber immediately after injection. At subsequent time points GFP+ cells accumulate on the surface of the iris and within the trabecular meshwork. GFP+ PEC are observed in the circulation at 24 and 48 hours after injection and are found in the spleen at 48 and 72 hours after injection but are not evident in the submandibular or cervical lymph nodes. Conclusions: These studies demonstrate that APC in the anterior segment of the eye egress through the trabecular meshwork and migrate to the spleen but not to regional lymph nodes. Our results imply that ACAID inducing APC initiate deviant immunity through venous circulation.
Keywords: ACAID • microscopy: light/fluorescence/immunohistochemistry • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)