Recipient HLA-DR3, tumour necrosis factor-a promoter allele-2 (tumour necrosis factor-2) and cytomegalovirus infection are inter- related risk factors for chronic rejection of liver grafts Paul C. Evans 1,² , Sheila Smith 2 , Gideon Hirsch®eld 1 , Eirini Rigopoulou 3 , Timothy G. Wreghitt 4 , Derek G.D. Wight 5 , Craig J. Taylor 2 , Graeme J.M. Alexander 1, * 1 Department of Medicine, University School of Clinical Medicine, Addenbrooke's NHS Trust, Hills Road, Cambridge, UK 2 Tissue Typing, University School of Clinical Medicine, Addenbrooke's NHS Trust, Hills Road, Cambridge, UK 3 Department of Surgery, University School of Clinical Medicine, Addenbrooke's NHS Trust, Hills Road, Cambridge, UK 4 Clinical Microbiology and Public Health Laboratory, University School of Clinical Medicine, Addenbrooke's NHS Trust, Hills Road, Cambridge, UK 5 Department of Histopathology, University School of Clinical Medicine, Addenbrooke's NHS Trust, Hills Road, Cambridge, UK Background/Aims: The tumour necrosis factor (TNF)-2 promoter allele, which elicits elevated expression of TNF-a, is in linkage disequilibrium with the extended haplotype HLA-A1-B8-DR3-DQ2. TNF-2 and HLA-DR3 have been implicated in renal and cardiac graft rejection and loss. Cytomegalovirus (CMV) infection has been associated with chronic allograft rejection. We examined the relationship between HLA-DR3, promoter allele TNF-2 and cytomega- lovirus in relation to chronic rejection following liver transplantation. Methods: (i) Retrospective analysis of HLA-DR3 was performed in 307 liver transplant recipients and 283 donors. (ii) Prospective analysis of TNF-a promoter allele status, HLA-DR3 status and cytomegalovirus infection was assessed in 123 recipients. Results: (i) Retrospective analysis. Recipient HLA-DR3 (relative risk 1.9; 95% C.I. 1.01±3.58) was a risk factor for chronic rejection. (ii) Prospective analysis. Recipient HLA-DR3 was a risk factor for chronic rejection (relative risk 3.41; 95% C.I. 1.66±7.03) which was elevated further by superimposed CMV infection (relative risk 5.01; 95% C.I. 2± 12.55). Recipient TNF-2 was associated with chronic rejection (relative risk 2.29; 95% C.I. 0.9±5.83) through linkage to HLA-DR3. Conclusions: Recipient HLA-DR3, TNF-2 status and CMV infection were inter-related risk factors for chronic rejection of liver grafts. q 2001 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved. Keywords: Liver transplant; Chronic rejection; HLA-DR3; Tumour necrosis factor-a; Cytomegalovirus 1. Introduction Chronic rejection (CR) is an untreatable mode of graft loss following liver transplantation [1,2]. Elevated levels of the pro-in¯ammatory cytokine, tumour necrosis factor-a (TNF-a) have been documented during acute [3] and chronic [4] rejection of liver grafts and may be pathogenic. The quantity of TNF-a produced by an individual is governed partly by the genetics of two TNF-a promoter alleles with polymorphisms at 2308 [5] and 2238 [6]. In vitro studies have shown that the TNF-2 promoter allele elicits higher basal and inducible expression compared to TNF-1 [7]. TNF-2 has been associated with acute rejection of renal [8] and heart [9] grafts and elevated production of TNF-a by the recipient has been proposed as a pathogenic mechanism. Other possibilities exist, however, because TNF-2 is strongly linked to HLA-A1, -B8 and -DR3 alleles [5] and the complement C4 null allele C4AQ0 [10] and this Journal of Hepatology 34 (2001) 711±715 0168-8278/01/$20.00 q 2001 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved. PII: S0168-8278(00)00101-X www.elsevier.com/locate/jhep Received 19 June 2000; received in revised form 21 October 2000; accepted 24 November 2000 * Corresponding author. Tel.: 144-1223-217026; fax: 144-1223- 216111. E-mail address: gja1000@cam.ac.uk (G.J.M. Alexander). ² Present address: Molecular Immunology Programme, The Babrahan Institute, Cambridge, UK.