New Approaches to Antibody Therapy

Abstract

The past years have seen the emergence of a new field in plastic surgery: composite tissue allotransplantation (CTA). While it has been used differently depending on context, CTA generally applies to the allotransplantation of vascularized tissues for the purpose of tissue reconstruction. While CTA has been performed for a few decades now (vascularized tendon and bone allotransplants were performed in select experimental settings as early as the 1980s and 1990s), the holy grail of CTA – the transplantation of vascularized tissues that contain a skin component – was achieved only recently (September 23, 1998) with the first human hand transplantation in Lyon (France). The allotransplantation of a hand, 54 years after the first kidney transplantation, was considered a landmark accomplishment. While the reconstructive aspects of the procedure were – and are – relatively straightforward, the skin is highly susceptible to immune rejection, and no immunosuppressive regimen prior to 1998 had been efficacious at preventing the rejection of a transplanted hand. Hand transplantation, and recently face transplantation, became possible with the advent of new immunosuppressive regimens, an era inaugurated by the introduction of cyclosporine in 1978. Ultimately, the combination regimen of tacrolimus (also called FK506), mycophenolate mofetil (MMF), and steroids fostered the first successful hand transplantation. In recent years, other immunosuppressive agents acting via different mechanisms have been introduced. While these agents are changing the way CTA recipients are induced or desensitized immediately following transplantation, it is important to point out that the maintenance immunosuppressive regimen following CTA is still roughly the same as it was at the time of the first procedures, when it was first established by Ustuner et al. To understand antibody therapies in CTA, it is important to consider our historical understanding of immune rejection and the difference between immunosuppression and immunomodulation as two different approaches toward preventing it.