Intragraft expression of recipient-type ABO blood group antigens: Long-term follow-up and histological features after liver transplantation
✍ Scribed by Yuichi Tanaka; Hironori Haga; Hiroto Egawa; Tomoko Okuno; Aya Miyagawa-Hayashino; Tatsuaki Tsuruyama; Michiyo Kambe; Hiroyuki Marusawa; Tsutomu Chiba; Toshiaki Manabe
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 335 KB
- Volume
- 11
- Category
- Article
- ISSN
- 1527-6465
- DOI
- 10.1002/lt.20415
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✦ Synopsis
Several reports have shown detection of recipient-type ABO histo-blood group antigens (r-ABOAg) in the liver allograft, which may represent either true intragraft chimerism or other events such as cell injury. Little is known about factors that affect the timing and extent of r-ABOAg expression in the graft. We examined 65 recipients who underwent ABO nonidentical living donor liver transplantation (61 compatible, 4 incompatible). Ninety-seven postoperative specimens (71 episode biopsies, 16 protocol biopsies, and 10 explanted allografts) were available for evaluation with immunohistochemistry of ABH blood type antigens. The expression of r-ABOAg was assessed in relation to histological and clinical factors. Capillaries in the portal tracts were the primary sites of r-ABOAg expression. The percentage of specimens showing r-ABOAg expression increased with lengthening of the post-transplantation period. Only 1 (4%) of 28 specimens showed endothelium with r-ABOAg within 1 year after the procedure, but 10 (29%) of 35 did between 1 and 5 years after transplantation and 21 (62%) of 34 after more than 5 years. Proportional analysis found that chronic rejection was a significant factor (P ؍ 0.006) for any r-ABOAg expression in the capillaries, and allograft portal fibrosis was a significant predictive factor for extensive r-ABOAg expression (seen in more than one third of the portal tracts) in the capillaries (P ؍ 0.017). Sex mismatch, age of recipients, age of donors, graft/recipient body weight ratio, and histology other than chronic rejection and fibrosis did not correlate with the expression of r-ABOAg. In conclusion, these observations suggest that portal capillaries with r-ABOAg are the results of graft injury and repair, and some of them may be neovessels of recipient origin. (