COMBINATION ANTI-CD2 AND ANTI-CD3 MONOCLONAL-ANTIBODIES INDUCE TOLERANCE WHILE ALTERING INTERLEUKIN-2, INTERLEUKIN-4, TUMOR-NECROSIS-FACTOR, AND TRANSFORMING GROWTH-FACTOR-BETA PRODUCTION
Kd. Chavin et al., COMBINATION ANTI-CD2 AND ANTI-CD3 MONOCLONAL-ANTIBODIES INDUCE TOLERANCE WHILE ALTERING INTERLEUKIN-2, INTERLEUKIN-4, TUMOR-NECROSIS-FACTOR, AND TRANSFORMING GROWTH-FACTOR-BETA PRODUCTION, Annals of surgery, 218(4), 1993, pp. 492-503
Objective These studies were designed to elucidate the mechanism by wh
ich signals delivered by anti-CD2 monoclonal antibody (MoAb) interfere
with activational signals delivered by anti-CD3 MoAb and induce long-
term graft survival and tolerance. Summary Background Data Anti-CD2 or
anti-CD3 MoAb can prolong allograft survival when administered alone.
In combination, they synergistically prolong survival while reducing
anti-CD3-associated cytokine toxicity. It was postulated that the mech
anism of synergism and reduced cytokine toxicity was related to anti-C
D2-induced alterations in anti-CD3-induced T-cell activation. Methods
C57BL/6 (H-2b) mouse hearts were transplanted to CBA (H-2k) mice. The
recipients received anti-CD2 and/or anti-CD3 MoAb intravenously only a
t the time of initial allografting. Serum from treated animals and cul
ture supernatants from lymphocytes stimulated in vitro with anti-CD3 w
ere examined for interleukin (IL)-2, -4, -6, and -10, tumor necrosis f
actor (TNF), and transforming growth factor-beta (TGFbeta). RNA was is
olated from lymphocytes from treated animals and examined for receptor
and cytokine gene expression by northern hybridization or reverse tra
nscribed and amplified by the polymerase chain reaction (PCR). Results
Anti-CD2 and anti-CD3 MoAbs alone prolonged graft survival (22.0 +/-
0.5 days and 28.0 +/- 0.5 days, respectively; p < 0.02 and p < 0.01 vs
. control, by Wilcoxon signed-rank test). Combined anti-CD2/anti-CD3 M
oAbs synergistically prolonged survival indefinitely (> 150 days, p <
0.01) while decreasing cytokine toxicity. Second donor-specific allogr
afts also showed long-term survival. The peak serum TNF concentration
(2100 units/mL) was reduced 78% by anti-CD2 treatment (455 units/mL).
Anti-CD2 inhibited anti-CD3-stimulated proliferation and in vitro prod
uction of IL-2 and IL-4, with no alteration of IL-6, IL-10, or TNF. Co
nversely, there was an increase in the immunosuppressive cytokine TGFb
eta. PCR analysis showed that anti-CD2 reduced anti-CD3-stimulated IL-
2 messenger RNA expression, and by northern analysis, anti-CD2 inhibit
ed anti-CD3-stimulated increases in messenger RNA for the CD2 and CD3
receptors themselves. Conclusions The combination of anti-CD2 and anti
-CD3 MoAbs induced a state of tolerance while decreasing anti-CD3-asso
ciated cytokine toxicity. The mechanism was related to anti-CD2-genera
ted alterations in T-cell activation and gene expression.