CYTOTOXIC T-LYMPHOCYTES AND ANTIBODIES AFTER ORTHOTROPIC PENETRATING KERATOPLASTY IN RATS TREATED WITH DICHLOROMETHYLENE DIPHOSPHONATE ENCAPSULATED LIPOSOMES
G. Vanderveen et al., CYTOTOXIC T-LYMPHOCYTES AND ANTIBODIES AFTER ORTHOTROPIC PENETRATING KERATOPLASTY IN RATS TREATED WITH DICHLOROMETHYLENE DIPHOSPHONATE ENCAPSULATED LIPOSOMES, Current eye research (Print), 17(10), 1998, pp. 1018-1026
Purpose. To investigate the immunological basis for the prolonged corn
eal allograft survival after subconjunctival injections of liposomes f
illed with dichloromethylene diphosphonate (Cl2MDP-LIP). Methods. F344
rats received orthotropic DA corneal grafts. One group of rats was tr
eated with subconjunctival injections of Cl2MDP-LIP on days 0, 2, 4, 6
and 8 postoperatively, the control groups received no treatment. Nine
teen or 42 days postoperatively cytotoxic T lymphocyte (CTL) activity
was measured in the lymph nodes draining the grafted and the contralat
eral eyes, in the spleen and the mesenteric lymph nodes Sera taken at
the same time points were tested for presence of lyric alloantibodies.
Results. On day 19 CTL activity in submandibular lymph nodes draining
the grafted eyes was similar in the 2 groups. In the mesenteric lymph
nodes high CTL activity was found in the untreated rats and low in th
e Cl2MDP-LIP rats. The spleen showed high CTL activity in the untreate
d group but no activity in the liposome group. Forty two days postoper
atively a decline in CTL activity was seen in both groups. Complement
dependent anti-donor antibodies were absent in the Cl2MDP-LIP group at
both time points whereas antibodies were present on days 19 and 42 in
the untreated group. Conclusions. Repeated subconjunctival injection
of Cl2MDP-LIP restricts the induction of cellular cytotoxicity against
donor antigens to the regional lymph nodes and suppresses cytotoxic a
ntibody formation.