LONG-TERM ANTIBODY-PRODUCTION IN CANINE LUNG ALLOGRAFTS - IMPLICATIONS IN PULMONARY IMMUNITY AND ASTHMA

Lung transplant recipients can become asthmatic if they receive donor lungs from asthmatics. The maintenance of sensitivity in the lung allo graft for inhaled allergens supports the concept that the mechanisms r esponsible for asthma are localized in the lungs, with a minimal syste mic component. Pulmonary immunity to inhaled allergens is one mechanis m which could be localized to the lung that would play a pivotal role in asthma, For example, the continued production of antibody to inhale d allergens in a human lung allograft could cause asthmatic responsive ness in the recipient. In this study, we tested the hypothesis that pu lmonary immune cells continue to produce antibody in a canine allograf t lung for relatively long times after transplantation. This was accom plished by immunizing four dogs by instillation of keyhole limpet hemo cyanin (KLH) into a single lung lobe. After two challenges, the immuni zed lung from each dog was transplanted into a nonimmune recipient. Im mune evaluations of recipients showed that anti-KLH antibody continued to be produced only in the donor lung for as long as 320 days after t ransplantation. Data from this study suggest that (1) immune cells in the lung can function independently from systemic immunity, (2) antibo dy production in the lung makes a significant contribution to blood an tibody levels, and (3) immune cells in donor lungs can continue to pro duce antibody for relatively long times after transplantation. Therefo re, immune cells in donor lungs from asthmatics could continue to prod uce antibody to allergens after transplantation, and this locally prod uced antibody may be responsible for the asthmatic responses observed in the recipients.