Allosensitization Following Bone Graft

Abstract

It is recognized that patients may become sensitized to donor-specific HLA antigens as a result of previous antigenic exposures, classically through previous transplantation, pregnancy, or blood transfusion. We present an unusual case of a patient who unexpectedly developed a range of anti-HLA antibodies following orthopedic surgery where a bone graft was deployed intraoperatively. We describe the case of a 52-year-old man awaiting a renal transplantation, undergoing elective orthopedic surgery requiring a small-volume bone graft. His postoperative antibody profile was found to be substantially changed compared to his previous negative samples, with the presence of HLA-DR, DQ, and DP specificities, at levels that would be likely to give a positive flow cytometry crossmatch and therefore according to local procedures required listing as unacceptable antigens for organ allocation. We perform a literature review of all previous cases of allosensitization following bone graft. This case is the first to demonstrate allosensitization following minor surgery with ;low-volume bone graft. Previous evidence is very limited and pertains only to massive osteochondral surgery for trauma or malignancy, and is confounded by potential concomitant blood transfusion. Clinicians should be aware of the risk of allosensitization where bone grafts are used.

Histological and immunohistochemical comparison of two different allogeneic bone grafting materials for alveolar ridge reconstruction: A prospective randomized trial in humans

“…This may suggest that trace amounts of MHC molecules are clinically not relevant. Despite the frequent use of human tissue products worldwide in a variety of medical specialties, formation of alloantibodies complicating future solid organ transplantation has rarely been reported for fresh‐frozen or cryopreserved bone . After using freeze‐dried or solvent dehydrated bone allografts from single or multiple donors for dental applications, such incidences have not been reported at all.…”

“…Despite the frequent use of human tissue products worldwide in a variety of medical specialties, formation of alloantibodies complicating future solid organ transplantation has rarely been reported for fresh-frozen or cryopreserved bone. 12,31 After using freeze-dried or solvent dehydrated bone allografts from single or multiple donors for dental applications, such incidences have not been reported at all. In our study, we did not detect any MHC1 molecules in the individual batches of bone allograft materials using ELISA.…”

“…Recent evidence for the detection of cellular remnants, such as cartilage tissues, cells or proteins in allogeneic substitutes, raised the question if immunological side effects may occur, resulting for example in sensitization against the allogeneic substitute. In a very recent study, Fretwurst et al showed that major histocompatibility complex molecules (MHC) were detectable in allogeneic bone blocks.…”

“…Extensive serological screening for potential infectious diseases, graft sterilization and establishment of a global biovigilance programme in combination with a long-term traceability of allografts have significantly improved safety, resulting only in a theoretical risk of transmission, for example, human immunodeficiency virus (HIV), hepatitis B virus (HBV), or hepatitis C virus (HCV) today. 6,8,9 Recent evidence for the detection of cellular remnants, such as cartilage tissues, cells or proteins in allogeneic substitutes, 10,11 raised the question if immunological side effects may occur, resulting for example in sensitization 12 against the allogeneic substitute. In a very recent study, Fretwurst et al showed that major histocompatibility complex molecules (MHC) were detectable in allogeneic bone blocks.…”

Allogeneic Bone Grafting Materials – Update of the Current Scientific Status

“…Infrequent reports, which have reported an allosensitization of recipients of human bone grafts, have shown to be mainly related to application of fresh or freshly frozen bone [26][27][28]. Only g.e.…”