We examined the proliferative response of blood CD4(+) cells to muscle acet
ylcholine receptor (AChR) subunits and the epitope repertoire of the epsilo
n and gamma subunits, in ocular myasthenia gravis (oMG) patients and health
y subjects. oMG patients seldom recognized all subunits. The frequency and
intensity of recognition was the same for all subunits, irrespective of the
disease duration. The responses in oMG were lower than in generalized myas
thenia gravis. Healthy subjects had frequent, low responses to one or more
subunits. oMG patients recognized several epitopes on the gamma and epsilon
subunits, that partially overlapped those recognized in gMG. The subunits
and epitopes recognized by individual oMG patients changed over time. Thus,
oMG patients have minimal and unstable sensitization of anti-AChR CD4(+) c
ells, in agreement with their low and inconsistent synthesis of anti-AChR a
ntibody. (C) 2000 Elsevier Science B.V. All rights reserved.