ABSTRACT

Although great strides have been made in the field of lung transplantation with respect to surgical technique, treatment of acute rejection and post-operative management, the long term success o f lung transplantation is limited by the development of chronic rejection as manifest by the bronchiolitis obliterans syndrome (BOS). In this chapter, we discuss the current basic scientific under­ standing of lung transplant rejection as it relates to the development of acute and chronic rejection. An overview of the basic immunological responses that lead to the development o f BOS is presented, including the respective roles o f HLA, non-HLA and lung specific antigens, humoral and cellular immune responses and regulatory T-cells. Taken together, these mechanisms represent our current knowledge for chronic lung transplant rejection and, hopefully, will result in novel therapeutics to combat this rate-limiting step in the long-term success o f lung transplantation.