Chronic rejection isan important cause ofgraft dysfunction and loss after the first posttransplant year [1].Two working hypotheses have evolved to explainthe etiology of the process. The first is an antigen-dependent phenomenon influenced by early immunological injury whereas the second is related to alloantigen-independent events contributing to progressive chronic graft dysfunction [2,3]. Our study, reported herein, focuses on the antigen-dependent aspects of chronic rejection. Several hypotheses have been proposed to explain the immunologic basis of chronic rejection. The first involvesrecurrent episodes of acute rejection that lead to protracted tissue damage and scarring [2,3].An alternative immune hypothesis to explain chronic rejection is that the immune-regulatory mechanisms that prevent acute rejection playa role in chronic rejection by supporting B cell responses and antibody formation. Therefore, chronic rejection may be a predominantly antibody- mediated form of graft damage..

Keywords: post-transplant antibody, chronic rejection