Jap. Gomes et al., PHENOTYPIC ANALYSIS OF RESIDENT LYMPHOID-CELLS IN THE CONJUNCTIVA ANDADNEXAL TISSUES OF RAT, Experimental Eye Research, 64(6), 1997, pp. 991-997
The conjunctival associated lymphoid tissue is considered to be an int
egral part of the mucosal immune system, Under normal circumstances im
mune mechanisms in mucosal associated lymphoid tissue of the gut and b
ronchus can selectively suppress, rather than enhance, immune responsi
veness to encountered antigens, inducing a state of tolerance. It is p
ossible that conjunctival associated lymphoid tissue can also induce a
state of tolerance to encountered antigens. Such a response may be ex
ploited to modulate immune mediated ocular disease. Enhanced tolerance
may protect the host against foreign antigen. Alternatively, under ce
rtain circumstances when the normal immune system is altered or disrup
ted the mucosal tissue may act to induce sensitisation and trigger imm
une mediated disease. The rat is frequently used as an animal model of
immune mediated eye disease, but the normal profile of immune cells i
n the rat conjunctiva has not been studied, This information is essent
ial for meaningful interpretation in the experimental situation. In th
is study we examined the immunophenotype of lymphoid tissue associated
with the conjunctiva, lacrimal gland and Harderian gland of the Lewis
rat. CD4(+), Ia(+) and the monocyte/macrophage population of cells we
re found predominantly in the substantia propria of the conjunctiva an
d interstitial connective tissue of the glands. CD8(+) cells were dist
ributed mainly in relation to the conjunctival and glandular epitheliu
m. Goblet cells stained strongly with the monoclonal antibody (MAb) MR
C OX-39, which is a marker for IL-2 receptors. The overall pattern of
distribution of immunocompetent cells in the rat was found to be simil
ar to that reported in humans. (C) 1997 Academic Press Limited.