A New Rat Model of Maxilla Allotransplantation

Abstract

We developed a rat model to test the effects of vascularized maxilla allotransplantation on composite maxillary substructures. Allograft maxilla transplantations were performed across the major histocompatibility barrier between 10 Lewis-Brown-Norway (RT1(n+l)) and 10 Lewis (RT1(l)) recipient rats under cyclosporin A monotherapy. Grafts were dissected along Le-Fort II osteotomy lines based on the common carotid artery and external jugular vein and transplanted to the anterior abdominal wall via microvascular anastomosis. Allografts were examined by tomography, flow cytometry, angiography, and histology. Three of the allografts survived up to 105 days without any signs of rejection. High level of donor-specific chimerism for T-cell and B-cell lineages was maintained in the peripheral blood. The incisors continued to grow; teeth buds, bone, cartilage, and mucosa remained intact. Moderate inflammation of the nasal, oral mucosa, and keratinous metaplasia was noted histologically. We created a maxilla allotransplantation model that allows the study of immunologic responses and demonstrates potential clinical applications based on the growth properties of the allograft.

Technical and Immunological Aspects of Face Transplantation

“…There were no signs of rejection up to 220 days in hemiface/calvaria model (7). Composite hemiface/mandible recipients survived up to 378 days, whereas maxilla allotransplants survived up to 105 days (6).…”

“…Siemionow et al introduced the first facial and scalp transplantation model in the rat in 2002 (2,3,4). This was followed by hemiface transplantation model, composite hemiface/calvaria model, composite hemiface/ mandible/tongue allograft transplantation model and composite maxilla allograft model (5,6,7).…”

The Technical and Anatomical Aspects of the World's First Near-Total Human Face and Maxilla Transplant

“…Numerous prior anatomical studies have been reported in the literature of potential transplant options for osteocutaneous transfer involving the use of the external carotid system with the internal maxillary vessels as the primary blood supply to the palate. [5][6][7][8][9][10] While the anterior wall of the maxilla can be vascularized based on the periosteal supply from the overlying soft tissue, which is supplied by the facial arterial system, the potential of the facial arterial system supplying the potential watershed area of the posterior hard palate had not previously been considered. The question remained of how much blood supply this region would get from mucosal arcades from the buccal mucosa intraorally and from Kiesselbach plexus communications to the posterior nasal vessels from the anterior nasal cavity.…”

Facial Transplantation

“…This model may serve as a new reconstructive option for coverage of the extensive head and neck deformities involving large bone and soft tissue defects. 58,59 7. Large Animal Model: A Dog Model of Hemifacial Transplant Thus far, there has been only one report on face transplantation performed in a large animal (dog) model.…”