Heterotopic heart transplantation was performed as previously described 33 (IACUC #M019M352), n=5 surgery survival animals per group. Recipients were administrated with a single dose of CTLA4-Ig (Bristol-Myers Squibb, Princeton, NJ) on day of transplant (d0, 500μg intraperitoneal). The grafts were monitored by daily palpation and graded from 4+ (strong beat) to 0 (no beat) by two individuals in a blinded manner and confirmed by laparotomy at the time of sacrifice 34 . Rejection was defined as beating score 1 (minimally palpable beat) or 0 (no palpable beat). The animals were sacrificed on the day of beating score 1 or at a designated time endpoint.
Due limitations imposed by the complex transgenic breeding strategy and surgical approach to obtain balanced cohorts, only male mice were included in the study. We acknowledge the limitations imposed by this design.
CTLA4-Ig has been widely described as a mean to achieve complete allogeneic tolerance in mice 35 (link), 36 (link), as well as immune regulation in humans 37 . The latter is achieved via complex immunologic mechanisms, including CD80/86-CD28 axis blockade 38 (link), 39 (link). In this study we used a sub-therapeutic CTLA4-Ig scheme to generate partial/transient allo-tolerance in transplanted recipients, aiming to resemble the drug-induced partial tolerance of actual human patients enrolled in the study.
Due limitations imposed by the complex transgenic breeding strategy and surgical approach to obtain balanced cohorts, only male mice were included in the study. We acknowledge the limitations imposed by this design.
CTLA4-Ig has been widely described as a mean to achieve complete allogeneic tolerance in mice 35 (link), 36 (link), as well as immune regulation in humans 37 . The latter is achieved via complex immunologic mechanisms, including CD80/86-CD28 axis blockade 38 (link), 39 (link). In this study we used a sub-therapeutic CTLA4-Ig scheme to generate partial/transient allo-tolerance in transplanted recipients, aiming to resemble the drug-induced partial tolerance of actual human patients enrolled in the study.
