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Pirfenidone delays the onset of obstructive airway disease in a murine heterotopic tracheal transplant model
S72
Abstracts
6.3 #71
PIRFENIDONE DELAYS THE ONSET OF OBSTRUCTIVE AIRWAY DISEASE IN A MURINE HETEROTOPIC TRACHEAL TRANSPLANT MODEL Brice W. McKane,1 Martin D. Jendrisak,1 Shawn Marshbank,2 Zahid Kaleem,3 G. A. Patterson,1 T. Mohanakumar.1,2 1Department of Surgery, Washington University School of Medicine, St. Louis, MO; 2Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO; 3Department of Pathology and Laboratory Medicine, VA Medical Center, Omaha, NE Chronic lung allograft rejection in the form of bronchiolitis obliterans syndrome remains a major long term cause for morbidity and mortality following lung transplantation. The purpose of our study was to prevent the development of Obstructive Airway Disease (OAD), a form of chronic rejection in a mouse tracheal allograft model using Pirfenidone, a novel anti–fibrotic agent. The study group consisted of 6 – 8 week old C57BL/6 mice which received heterotopically transplanted completely mismatched tracheas from BALB/c donors. Pirfenidone was administered to the study group daily. Control mice received tracheal transplants but no Pirfenidone. Animals were sacrificed on days 15, 28, and 60 post transplantation. Allografts were removed for histopathologic evaluation. Control mice developed OAD defined by luminal occlusion, loss of tracheal epithelium and a chronic inflammatory infiltrate by day 28 (Fig1a). Five of five mice (100%) receiving Pirfenidone failed to develop evidence of OAD at day 28 (Fig 1b). At the conclusion of the study on day 60 post transplantation, there was no evidence of OAD in 3 of 5 mice (60%) receiving Pirfenidone. The remaining two mice (40%) developed OAD at this time point. In this model for chronic lung allograft rejection, we have been able to delay the onset and progression of OAD in a murine heterotopic tracheal transplant model until at least day 60 by treatment using Pirfenidone, a broad spectrum anti–fibrotic agent. These findings may have implications in the prevention of bronchiolitis obliterans syndrome in humans.
6.4 #72
FREQUENCY OF DONOR–SPECIFIC IFN–␥–PRODUCING LYMPHOCYTES CORRELATES WITH POST–TRANSPLANT COURSE OF LIVER TRANSPLANT RECIPIENTS Anat R. Tambur,1 Peter S. Heeger,2 Tirza Klein,3 Ziv Ben–Ari,3 Nancy D. Herrera,1 Eytan Mor.3 1Pathology, Rush Med Ctr, Chicago, IL; 2Transplantation, Cleveland Clinic, Cleveland, OH; 3Transplantation, Rabin Med Ctr, Petach–Tiqva, Israel Immunosuppression (IS) protocols, while designed to minimize rejection episodes in allograft recipients, compromise the patients’ immune surveillance exposing them to infections and malignancies. Currently, physicians relay mainly on their gestalt to determine the extent of IS tapering. Unfortunately, patients intolerant of withdrawal may develop severe rejection episodes. Thus, the ability to monitor the immunologic status of an allograft recipient towards the transplanted organ is crucial for judicious individualization of IS protocols. In a pilot study, the frequency of donor–specific IFN–␥ producing lymphocytes was monitored in 10 liver transplant recipients. PBL specimens were obtained from consented recipients at specific intervals (pre–transplant; 1–; 3–; 6 –; 12– and 24 months post transplant). Donor cells were obtained at time of organ harvest. The ability of the recipient to secret IFN–␥ was measured using a cocktail of anti–CD3/IL–2 for maximal responses (positive control [PC]) and a mixture of cells from 3 healthy, HLA disparate, controls (Pool control [Pool]). Negative control (NC) was determined as responses against autologous cells. Donor specific responses were calculated using the following formula: [Rvs.D – NC/PC] : [RvsPool – NC/PC]. In agreement with our previous data, the majority of patients were rather anergic prior to transplant, as indicated by their proportionally low responses to the PC. With some exceptions, the responses against the Pool resembled the archetype of the PC. However, in the majority of patients, the frequency of IFN–␥ producing cells with donor specificity remained low at 6 –12 months post transplantation. In the 7 patients with 12 months follow up the donor response is 0 –5.7% (mean 1.27%) in contrast to 1.2–17% (mean 7.16%) for Pool response. Hyporesponsiveness (as measured by the above formula) is seen in 4 of these 7 patients. Interestingly, 3 of these 4 patients have severe recurrent disease early after transplant. Continue follow up of these patients and others to verify the long–term clinical significance of our results is in progress.
Abstracts
6.3 #71
PIRFENIDONE DELAYS THE ONSET OF OBSTRUCTIVE AIRWAY DISEASE IN A MURINE HETEROTOPIC TRACHEAL TRANSPLANT MODEL Brice W. McKane,1 Martin D. Jendrisak,1 Shawn Marshbank,2 Zahid Kaleem,3 G. A. Patterson,1 T. Mohanakumar.1,2 1Department of Surgery, Washington University School of Medicine, St. Louis, MO; 2Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO; 3Department of Pathology and Laboratory Medicine, VA Medical Center, Omaha, NE Chronic lung allograft rejection in the form of bronchiolitis obliterans syndrome remains a major long term cause for morbidity and mortality following lung transplantation. The purpose of our study was to prevent the development of Obstructive Airway Disease (OAD), a form of chronic rejection in a mouse tracheal allograft model using Pirfenidone, a novel anti–fibrotic agent. The study group consisted of 6 – 8 week old C57BL/6 mice which received heterotopically transplanted completely mismatched tracheas from BALB/c donors. Pirfenidone was administered to the study group daily. Control mice received tracheal transplants but no Pirfenidone. Animals were sacrificed on days 15, 28, and 60 post transplantation. Allografts were removed for histopathologic evaluation. Control mice developed OAD defined by luminal occlusion, loss of tracheal epithelium and a chronic inflammatory infiltrate by day 28 (Fig1a). Five of five mice (100%) receiving Pirfenidone failed to develop evidence of OAD at day 28 (Fig 1b). At the conclusion of the study on day 60 post transplantation, there was no evidence of OAD in 3 of 5 mice (60%) receiving Pirfenidone. The remaining two mice (40%) developed OAD at this time point. In this model for chronic lung allograft rejection, we have been able to delay the onset and progression of OAD in a murine heterotopic tracheal transplant model until at least day 60 by treatment using Pirfenidone, a broad spectrum anti–fibrotic agent. These findings may have implications in the prevention of bronchiolitis obliterans syndrome in humans.
6.4 #72
FREQUENCY OF DONOR–SPECIFIC IFN–␥–PRODUCING LYMPHOCYTES CORRELATES WITH POST–TRANSPLANT COURSE OF LIVER TRANSPLANT RECIPIENTS Anat R. Tambur,1 Peter S. Heeger,2 Tirza Klein,3 Ziv Ben–Ari,3 Nancy D. Herrera,1 Eytan Mor.3 1Pathology, Rush Med Ctr, Chicago, IL; 2Transplantation, Cleveland Clinic, Cleveland, OH; 3Transplantation, Rabin Med Ctr, Petach–Tiqva, Israel Immunosuppression (IS) protocols, while designed to minimize rejection episodes in allograft recipients, compromise the patients’ immune surveillance exposing them to infections and malignancies. Currently, physicians relay mainly on their gestalt to determine the extent of IS tapering. Unfortunately, patients intolerant of withdrawal may develop severe rejection episodes. Thus, the ability to monitor the immunologic status of an allograft recipient towards the transplanted organ is crucial for judicious individualization of IS protocols. In a pilot study, the frequency of donor–specific IFN–␥ producing lymphocytes was monitored in 10 liver transplant recipients. PBL specimens were obtained from consented recipients at specific intervals (pre–transplant; 1–; 3–; 6 –; 12– and 24 months post transplant). Donor cells were obtained at time of organ harvest. The ability of the recipient to secret IFN–␥ was measured using a cocktail of anti–CD3/IL–2 for maximal responses (positive control [PC]) and a mixture of cells from 3 healthy, HLA disparate, controls (Pool control [Pool]). Negative control (NC) was determined as responses against autologous cells. Donor specific responses were calculated using the following formula: [Rvs.D – NC/PC] : [RvsPool – NC/PC]. In agreement with our previous data, the majority of patients were rather anergic prior to transplant, as indicated by their proportionally low responses to the PC. With some exceptions, the responses against the Pool resembled the archetype of the PC. However, in the majority of patients, the frequency of IFN–␥ producing cells with donor specificity remained low at 6 –12 months post transplantation. In the 7 patients with 12 months follow up the donor response is 0 –5.7% (mean 1.27%) in contrast to 1.2–17% (mean 7.16%) for Pool response. Hyporesponsiveness (as measured by the above formula) is seen in 4 of these 7 patients. Interestingly, 3 of these 4 patients have severe recurrent disease early after transplant. Continue follow up of these patients and others to verify the long–term clinical significance of our results is in progress.