Both groups were randomly analyzed at 4 or 18 weeks. Bone remodeling areas (inner and outer cortical samples) were labeled and laser capture microdissected. Analysis of sex-mismatch genes by real-time reverse transcription-polymerase chain reaction
provided the relative Expression Ratio (rER) of donor (female) to recipient (male) cells. The rER was 0.456 ± 0.266 at 4 weeks and 0.749 ± 0.387 at 18 weeks (p = 0.09) Alisertib molecular weight in allotransplants. In isotransplants, the rER was 0.412 ± 0.239 and 0.467 ± 0.252 at 4 and 18 weeks, respectively (p = 0.21). At 4 weeks, the rER at the outer cortical area of isotransplants was significantly lower in isotransplants as compared with allotransplants (0.247 ± 0.181 vs. 0.549 ± 0.184, p = 0.007). Cells in the inner and outer cortical bone remodeling areas in isotransplants were mainly donor derived (rER < 0.5) at 18 weeks, whereas allotransplants contained mainly recipient-derived cells (rER > 0.5) at 18 weeks. Selleck Ulixertinib Applying novel methodology, we describe detailed cell traffic in vascularized bone transplants, elaborating our comprehension on bone transplantation. © 2013 Wiley Periodicals, Inc. Microsc. Res. Tech. 34:37–43, 2013. Skeletal reconstruction of large segmental bone defects following trauma, infection, avascular bone necrosis, or tumor challenges the reconstructive surgeon. Especially in difficult clinical circumstances, when soft tissue loss and ischemia is abundant, reconstruction
with conventional almost (cryopreserved) graft is susceptible to complications.[1-3] In such cases, vascularized bone autografts are preferably used to optimize revascularization and bone incorporation. However,
there are limitations to this technique due to restricted availability from a few expendable sites, suboptimal size, and shape match as well as potential for donor site morbidity. An alternative source is vascularized bone allotransplantation (VBAT), defined as the transplantation of living allogenic bone with microsurgical reconstruction of its nutrient blood supply. A VBAT procured from a donor could combine the desirable healing characteristics of vascularized grafts with the structural stability of cryopreserved allografts. It would further eliminate morbidity, allow close matching of defect size and shape, and possibly maintain the desirable attributes of living autografts. Allotransplants require long-term immune modulation to prevent rejection and maintain transplant viability. This is problematic, as long-term immunosuppressive therapy carries a considerable risk for neoplasm, infection as well as metabolic and toxic side effects. The search for more effective immune modulation protocols applicable for musculoskeletal tissues is promising and continues at present.[6-9] Prior to implementing bone allotransplantation clinically, it is essential to understand the complex underlying biology following the introduction of living donor bone into recipient tissue.