Early posttransplant inflammation promotes the development of alloimmunity and chronic human lung allograft rejection.

BACKGROUND: Chronic human lung allograft rejection, represented by bronchiolitis obliterans syndrome (BOS), is the single most important factor that limits the long-term survival following lung transplantation (LT). However, the pathogenesis of BOS remains unclear. We hypothesized that the early posttransplant inflammation would promote the development of donor anti-human leukocyte antigen (HLA) alloimmunity and predispose to BOS. METHODS: Serum levels of interleukin (IL)-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-15, IL-17, Eotaxin, IP-10, MIG, MCP-1, MIP-1alpha, MIP-1beta, RANTES, tumor necrosis factor (TNF)-alpha, interferon (IFN)-alpha, IFN-gamma, granulocyte-macrophage colony-stimulating factor, IL-1Ralpha, and IL-2R were serially analyzed in 31 BOS+ and matched 31 BOS- patients using quantitative multiplex bead immunoassays. Donor-specific HLA class II cellular immunity was analyzed using enzyme-linked immunospot (ELISPOT) by testing recipient peripheral blood mononuclear cells against mismatched donor HLA-DR peptides. Anti-HLA class II antibodies were monitored using flow panel reactive antibodies. RESULTS: There was early posttransplant elevation in basal serum levels of proinflammatory chemokines IP-10 and MCP-1 and Th1-cytokines IL-1beta, IL-2, IL-12, and IL-15 in BOS+ patients, compared to BOS- and normal subjects. In addition, a threefold decline in IL-10 levels was found during BOS development. BOS+ patients revealed increased development of HLA class II alloantibodies and Th1-predominant donor-specific cellular immunity with high frequency of IFN-gamma and low IL-5 producing T-cells. CONCLUSION: Early posttransplant elevation of proinflammatory mediators is associated with alloimmunity and chronic human lung allograft rejection.

Thrombotic microangiopathy after lung transplantation.

BACKGROUND: Thrombotic microangiopathy (TMA) is a well-recognized complication after transplantation. The purpose of this study was to describe our center's experience with this complication after lung transplantation. METHODS: We retrospectively reviewed cases of TMA among patients who underwent lung transplantation between January 1, 1999 and December 31, 2003 (n = 257). The cases were characterized and the outcomes were analyzed. Univariate and multivariate Cox regression models were constructed to identify potential risk factors for TMA. RESULTS: Twenty-four cases of TMA developed in 20 recipients. Thirteen cases occurred in the setting of another illness and 11 cases were isolated complications. Multivariate Cox regression models identified female gender, history of TMA, and the immunosuppressive regimen as independent predictors of TMA. Maintenance immunosuppression with the combination of a calcineurin inhibitor and sirolimus carried a significantly higher risk of TMA than a calcineurin inhibitor alone. After the diagnosis of TMA, calcineurin inhibitors were stopped in 18 cases; however, in 6 cases in which the onset of TMA coincided with the addition of sirolimus to a calcineurin inhibitor, only sirolimus was discontinued. Plasmapheresis was performed for severe cases (n = 10). TMA remitted in all cases, and an alternate calcineurin inhibitor was introduced in 14 cases. TMA recurred in 4 recipients, a median 253 days after the initial episode. The median survival after the onset of TMA was 377 days. CONCLUSION: TMA is a serious complication after lung transplantation, and the risk is highest when sirolimus is used in combination with a calcineurin inhibitor.

Elevated soluble CD30 correlates with development of bronchiolitis obliterans syndrome following lung transplantation.

BACKGROUND: The long-term function of lung transplants is limited by chronic rejection (bronchiolitis obliterans syndrome, BOS). Due to lack of specific markers, BOS is diagnosed clinically. Because there is strong evidence that alloimmunity plays a significant role in the pathogenesis of BOS, we investigated whether soluble CD30 (sCD30), a T-cell activation marker, would correlate with BOS. METHODS: Sera collected serially from BOS+ (n = 20) and matched BOS- (n = 20) lung transplant (LT) patients were analyzed for sCD30 by enzyme-linked immunosorbent assay. Pretransplant sera and sera from normal donors were also analyzed. RESULTS: PreLT levels were comparable to normal subjects. However, posttransplant there was a significant elevation in sCD30 levels during BOS development in all BOS+ patients, compared to BOS- (mean 139.8+/-10.7 vs. 14.8+/-2.7 U/ml, P < 0.001). sCD30 levels declined in the BOS+ patients but were still elevated compared to BOS- (48.52+/-5.04 vs. 7.19+/-2.9, P < 0.0001). CONCLUSIONS: We conclude that sCD30 may represent a novel marker to monitor the development of BOS.

The significance of a single episode of minimal acute rejection after lung transplantation.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) remains the leading obstacle to better long-term outcomes after lung transplantation. Acute rejection has been identified as the primary risk factor for BOS, but the impact of minimal acute rejection, especially a solitary episode, has usually been discounted as clinically insignificant. METHODS: We performed a retrospective cohort study of 259 adult lung transplant recipients to determine the risk of BOS associated with a single episode of A1 rejection, without recurrence or subsequent progression to a higher grade. The cohort was divided into 3 groups based on the severity of acute rejection (none, single episode of A1, and single episode of A2). We determined the risks of BOS stages 1, 2, 3, and death for each group using univariate and multivariate Cox regression analyses. RESULTS: A solitary episode of A1 rejection was a significant risk factor for BOS stages 1 and 2, but not stage 3 or death, in the univariate analysis. Multivariate Cox regression models confirmed that the risk of BOS attributable to a single episode of A1 rejection was independent of other potential risk factors, such as community acquired respiratory viral infections, number of HLA mismatches, and cytomegalovirus pneumonitis. Likewise, univariate and multivariate analyses demonstrated that a single episode of A2 rejection was a significant risk factor for all stages of BOS but not death. CONCLUSIONS: A single episode of minimal acute rejection without recurrence or subsequent progression to a higher grade is a significant predictor of BOS independent of other risk factors.

Reliability for grading acute rejection and airway inflammation after lung transplantation.

BACKGROUND: The Lung Rejection Study Group (LRSG) created a scheme for grading acute allograft rejection in 1990 and then revised it in 1996, but virtually no studies have evaluated the reliability of this formulation. This investigation assessed the reliability of the current LRSG system by determining inter- and intrareader agreement for grading transbronchial biopsy samples from lung transplant recipients. METHODS: Biopsy samples from a cohort of 204 recipients were reviewed and classified by a single pathologist who was blinded to original interpretations. The "A" and "B" rejection grades from this contemporary review were compared with original grades by the kappa statistic. RESULTS: For "A" grading, weighted kappa was 0.65 (95% confidence interval [CI] 0.60-0.70) for interreader agreement (n = 529 specimens) and 0.65 (95% CI 0.53-0.76) for intrareader agreement (n = 97 specimens). For "B" grading, weighted kappa was 0.26 (95% CI 0.14-0.39) for interreader agreement (n = 164 specimens) and 0.33 (95% CI 0.15-0.51) for intrareader agreement (n = 58 specimens). CONCLUSIONS: On the basis of the analysis of the LRSG scheme, "A" grades exhibit very good reliability, but "B" grades have only fair reliability, and steps to improve this shortcoming should be taken.

Abdominal-pelvic lymphoproliferative disease after lung transplantation: presentation and outcome.

BACKGROUND: Lymphoproliferative disease (LPD) is a well-recognized complication after lung transplantation. However, its presentation in the abdomen and pelvis has not been previously detailed. METHODS: We retrospectively identified cases of abdominal-pelvic LPD in lung transplant recipients. The cases were characterized clinically, and the outcomes were analyzed. RESULTS: Abdominal-pelvic LPD was identified in 19 of 603 adult patients who underwent lung or heart-lung transplantation at Barnes-Jewish Hospital between July 1, 1988 and December 31, 2001. The median time from transplantation to the onset of LPD was 5.8 years. Three cases presented early after transplantation (median, 175 days), and 16 cases presented late (median, 2,255 days). The time to diagnosis of LPD was significantly shorter for Epstein-Barr virus (EBV)-seronegative than for EBV-seropositive recipients (median, 175 vs. 2255 days; log-rank, P<0.001). Seventeen cases were non-Hodgkin's lymphomas, one was a Burkitt's lymphoma, and one was an atypical lymphoid proliferation. Among the 19 cases, 12 involved the gastrointestinal tract and 7 occurred in other sites. Immunosuppressive therapy was decreased in all patients. Eleven underwent surgical resection, and nine received chemotherapy. Sixteen patients have died, and 14 deaths were attributable to LPD. The median time from the diagnosis of LPD to death was 68 days. CONCLUSIONS: Abdominal-pelvic LPD is typically a late complication after lung transplantation; however, when it occurs early, it may be related to a primary EBV infection. This form of LPD is most frequently a non-Hodgkin's lymphoma, and despite aggressive therapy, the prognosis is poor.

Interleukin-6 and interferon-gamma gene polymorphisms in the development of bronchiolitis obliterans syndrome after lung transplantation.

BACKGROUND: A number of genetic polymorphisms have been shown to regulate the production and secretion of tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta1, interferon (IFN)-gamma, interleukin (IL)-6, and IL-10. Several of these genetic polymorphisms have been shown to be associated with either acute or chronic rejection of kidney, liver, and heart allografts and with development of allograft fibrosis after lung transplantation. The aim of this study was to assess the effect of these genetic polymorphisms on the development of bronchiolitis obliterans syndrome (BOS) after lung transplantation. METHODS: Genetic polymorphisms were detected by means of polymerase chain reaction in 93 lung allograft recipients for functional polymorphisms in the TNF-alpha (-308), TGF-beta1 (+869 and +915), IL-6 (-174), IFN-gamma (+874), and IL-10 (-1082, -819, and -592) genes. Then, a correlation between BOS development and the presence of these cytokine genotypes was determined using Kaplan-Meier actuarial analysis. RESULTS: A significant correlation was detected between the presence of high-expression polymorphisms of the IL-6 and IFN-gamma genes and BOS development after lung transplantation (P =0.045 and 0.039, respectively). Also, patients with high-expression polymorphisms in both genes developed BOS significantly earlier than patients with low-expression polymorphisms in one or both genes, suggesting a synergistic effect of the alleles during BOS pathogenesis (P =0.016). No correlation was detected between polymorphisms of the TNF-alpha, TGF-beta1, and IL-10 genes and development of BOS after lung transplantation. CONCLUSIONS: The presence of high-expression polymorphisms at position -174 of the IL-6 gene and position +874 of the IFN-gamma gene significantly increases the risk for BOS development after lung transplantation.

Yield of surveillance bronchoscopy for acute rejection and lymphocytic bronchitis/bronchiolitis after lung transplantation.

BACKGROUND: Better understanding of the timing and pattern of surveillance bronchoscopy findings after lung transplantation could influence the timing and frequency of surveillance bronchoscopy. We present our surveillance bronchoscopy experience and test the hypothesis that patients not encountering early acute rejection or lymphocytic bronchitis/bronchiolitis are less likely to have subsequent occult occurrences in the 1st year after lung transplantation. METHODS: We conducted a retrospective study of 204 patients who underword transplantation between 1996 and 2000. Based on contemporary biopsy-specimen grading in the first 100 days, we formed 2 groups: No Early Rejection and Early Rejection. We compared subsequent yields of surveillance bronchoscopy and the incidence of acute rejection or of lymphocytic bronchitis/bronchiolitis. RESULTS: We reviewed 645 biopsies taken from 204 recipients during the first 100 days to classify patients into a No Early Rejection Group (n=67) or an Early Rejection Group (n=137). Yield of surveillance bronchoscopy for acute rejection or lymphocytic bronchitis/bronchiolitis was 31% with the greatest yield during the first 30 days (45%), and then decreasing to 26% (p <0.001). After Day 100, 71% of occult acute rejection episodes involved minimal (A1) lesions. Yield of surveillance bronchoscopy after Day 100 was 20% in the No Early Rejection Group and was 27% in the Early Rejection Group (p=0.22). Incidence of acute rejection or lymphocytic bronchitis/bronchiolitis after Day 100 was 41% in the No Early Rejection Group and was 50% in the Early Rejection Group (p=0.17). CONCLUSION: Surveillance bronchoscopy detects occult acute rejection or lymphocytic bronchitis/bronchiolitis in approximately one-third of biopsy specimens during the 1st year, with the majority of late abnormalities being minimal (A1) rejection. The absence of acute rejection or lymphocytic bronchitis/bronchiolitis during the first 100 days does not predict freedom from such events in the remainder of the 1st year.

Correlation between interleukin-15 and granzyme B expression and acute lung allograft rejection.

The levels of interleukin (IL)-15 and granzyme B mRNA expression have been correlated with acute rejection episodes of kidney and heart allografts. Thus, the purpose of this study was to determine whether a correlation exists between the expression of IL-15 and granzyme B and acute lung allograft rejection. Toward this, the levels of IL-15 and granzyme B mRNA expression were determined in bronchoalveolar lavage-derived alveolar macrophages and total cells, respectively, from lung transplant patients with stable lung allograft function and patients undergoing acute rejection episodes. The expression levels of IL-15 mRNA was significantly higher in the patients undergoing acute rejection as compared to patients with stable lung function (P=0.02). The expression levels of granzyme B mRNA was also significantly higher in the patients undergoing acute rejection as compared to patients with stable lung function (P=0.005). The Receiver-Operating-Characteristic curve demonstrated that acute rejection can be predicted with a sensitivity of 94% and specificity of 67% with the use of a cutoff value of 3.1 fg of granzyme B mRNA per microgram of total RNA (or 71% sensitivity and 75% specificity of a cutoff value of 9.1 fg/microg). These data indicate that IL-15 secreted by activated alveolar macrophages and granzyme B secreted by activated CD8+ cytotoxic T lymphocytes play important roles in the process of acute lung allograft rejection.

Efficacy of extracorporeal photopheresis in clearance of antibodies to donor-specific and lung-specific antigens in lung transplant recipients.

BACKGROUND: Extracorporeal photopheresis (ECP) has been used to treat chronic rejection after lung transplantation (LTx). We investigated the effect of ECP on several immune parameters that have been associated with poor lung function, including donor-specific antibodies (DSA) to human leukocyte antigen (HLA), antibodies against the lung-associated self-antigens (SAg), Kα1-tubulin (Kα1T), collagen I and V, and circulating levels of pro-inflammatory and anti-inflammatory cytokines. METHODS: Sera were collected from post-LTx patients diagnosed with bronchiolitis obliterans before and 6 months after initiation of ECP. DSA and cytokine levels were measured by Luminex (Invitrogen, Carlsbad, CA). Changes in lung function over the 6 months preceding and after the initiation of ECP were measured by retrospective analysis of spirometry performed at routine clinic visits. RESULTS: ECP was associated with a significant decline in DSA levels as well as antibodies to lung-associated SAg. ECP also reduced circulating levels of pro-inflammatory cytokines and increased levels of anti-inflammatory cytokines. These immunologic changes were associated with a significant 63% reduction in the rate of decline in forced expiratory volume in 1 second over a 1-year period. Though statistically insignificant, a higher rate of clearance of antibodies to lung-associated SAg was strongly associated with better response to ECP. CONCLUSIONS: ECP is associated with a reduction in the levels of circulating DSA, antibodies to lung-associated SAg (Kα1T, collagen I, and collagen V), and circulating levels of several pro-inflammatory cytokines. We propose that these changes contribute to the beneficial effect of ECP in reducing the decline in lung function.

Pre-transplant antibodies to Kα1 tubulin and collagen-V in lung transplantation: clinical correlations.

BACKGROUND: Immune responses to lung-associated self-antigens (SAgs) have been implicated in chronic lung allograft rejection. The goals of this study were to determine the prevalence of pre-existing antibodies (Abs) to the SAgs in pulmonary diseases and the association between pre-existing Abs to SAgs and the development of primary graft dysfunction (PGD), donor-specific antibodies (DSA), and chronic rejection. METHODS: Pre- and post-transplant sera were analyzed from 317 lung transplant (LTx) recipients between 2000 and 2011 with diagnosis of chronic obstructive disease (n = 161), idiopathic pulmonary fibrosis (IPF; n = 50), cystic fibrosis (CF; n = 55), and others (n = 51). Samples were analyzed for Abs to SAgs by enzyme-linked immunosorbent assay, and DSA and cytokines by Luminex. The clinical diagnosis of PGD and bronchiolitis obliterans syndrome (BOS) was based on International Society for Heart and Lung Transplantation guidelines. RESULTS: The overall prevalence of Abs to SAgs was 22.71%, including 18% in chronic obstructive pulmonary disease (p = 0.033), 34% in IPF (p = 0.0006), 29% in CF (p = 0.0023), and 19.6% in other diagnoses (p = 0.044). The incidence of PGD (88% vs 54%, p < 0.05), DSA (70% vs 45%, p < 0.01), and BOS (90% vs 38% (p < 0.001) after LTx was significantly higher in patients with pre-LTx Abs to SAgs than without. Pro-inflammatory cytokines (interleukin-1ß, interleukin-17, and interferon-γ) were elevated in patients who had pre-LTx Abs to SAgs, along with a reduction in anti-inflammatory interleukin-10. CONCLUSIONS: Patients with IPF and CF have the highest prevalence of Abs to SAgs. Patients with pre-existing Abs to SAgs are at increased risk for development of PGD, DSA, and BOS. Strategies to remove pre-existing Abs to SAgs should be considered to improve lung allograft outcome.

Alloimmunity-induced autoimmunity as a potential mechanism in the pathogenesis of chronic rejection of human lung allografts.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) is a major cause of morbidity and mortality after lung transplantation (LTx). We sought to better understand the relationship between alloimmune responses and autoimmunity and, subsequently, how autoimmunity leads to chronic rejection. METHODS: We analyzed the development of donor-specific antibodies (Abs) in LTx by flow PRA and the development of Abs to K-α1 tubulin (K-α1T) and collagen V (ColV) by ELISA. The frequency of K-α1T- and ColV-specific T cells that secrete IFN-γ, IL-17 and IL-10 in LTx recipients was measured by ELISPOT. RESULTS: In a retrospective analysis of 42 LTx recipients, we demonstrated a strong correlation between development of donor-specific anti-HLA Abs, Abs to self-antigens and BOS (p < 0.05). To test the hypothesis that alloimmunity is related to an immune response to self-antigens, we analyzed 103 LTx patients prospectively for the development of donor-specific Abs (DSA) and Abs to self-antigens. A total of 42.7% of recipients developed DSA and 30.1% developed Abs to K-α1T and ColV. Development of DSA preceded development of Abs to self-antigens. BOS(+) patients had higher frequency of T cells secreting IL-17 (p < 0.01) and IFN-γ (p < 0.05) with decreased IL-10 (p < 0.05) when compared with BOS(-) patients. CONCLUSIONS: Based on these results we propose that alloimmune responses to donor HLA can induce autoimmune responses to airway epithelial self-antigens, characterized by activation of the IL-17 pathway. These immune responses to self-antigens along with alloimmunity contribute to the pathogenesis of BOS. Strategies to prevent development of autoimmunity may be play a key role in preventing the development of chronic rejection.

Anti-human leukocyte antigen antibodies and preemptive antibody-directed therapy after lung transplantation.

BACKGROUND: Because the development of donor-specific anti-human leukocyte antigen (HLA) antibodies (DSA) after lung transplantation has been associated with acute and chronic rejection, we implemented a clinical protocol to screen all transplant recipients for DSA and preemptively treat those who developed DSA with rituximab and intravenous immune globulin (IVIG), or IVIG alone. METHODS: We conducted a prospective observational study of this protocol and used the LABScreen Single Antigen assay to detect DSA after transplantation. We compared the incidence of acute rejection, lymphocytic bronchiolitis, and bronchiolitis obliterans syndrome (BOS) between those who developed DSA and those who did not using Cox proportional hazards models. We used the Kaplan-Meier method to compare freedom from BOS and survival between those who had persistent DSA and those who had successful depletion of DSA. RESULTS: Among 116 recipients screened, DSA developed in 65 during the study period. Those who developed DSA and received antibody-directed therapy had a similar incidence of acute rejection, lymphocytic bronchiolitis, and BOS as those who did not develop DSA. Furthermore, recipients who had successful depletion of DSA had greater freedom from BOS and better survival than those who had persistent DSA. Finally, those treated for DSA had a similar incidence of infectious complications as those who did not develop DSA. CONCLUSIONS: The development of DSA is surprisingly common after lung transplantation. Antibody-directed therapy may reduce the risk of rejection associated with DSA, but a randomized controlled trial is necessary to critically evaluate the efficacy of this treatment protocol.

Increased erythrocyte C4D is associated with known alloantibody and autoantibody markers of antibody-mediated rejection in human lung transplant recipients.

BACKGROUND: Immune responses to mismatched donor human leukocyte antigens (HLA) are important in the pathogenesis of chronic rejection. This study evaluated whether erythrocyte-bound C4d (E-C4d) is associated with known alloimmune and autoimmune markers of antibody-mediated rejection after human lung transplantation (LTx). METHODS: Flow cytometry was used to analyze 22 LTx recipients and 15 healthy individuals for E-C4d. Development of antibodies to donor-mismatched HLA (donor-specific antibody [DSA]) and antibodies to HLA were determined using the solid-phase method by Luminex. Development of antibodies to self-antigens, K-alpha-1-tubulin (KA1T) and collagen V (Col-V), were measured by enzyme-linked immunosorbent assay. C3d deposition in lung biopsy specimens was determined by immunohistochemical staining. RESULTS: Percent E-C4d (%E-C4d) levels were 19.9% in LTx patients vs 3.7% in healthy individuals (p = 0.02). DSA+ patients had higher E-C4d levels than DSA- patients (34.1% vs 16.7%, p = 0.02). In 5 patients with preformed anti-HLA, E-C4d levels were not significantly different vs 13 patients without detectable anti-HLA (p = 0.1). E-C4d levels were higher in patients who developed antibodies to KA1T (p = 0.02) and Col-V (p = 0.03). Recipients with C3d-positive tissue deposition had higher E-C4d levels than patients with C3d-negative biopsy results (p = 0.01). CONCLUSIONS: Increased %E-C4d levels are found in patients with positive DSA, high antibody titers to KA1T and Col-V, and have C3d+ lung biopsy findings. Therefore, %E-C4d can serve as a potential marker for antibody-mediated rejection after LTx.

De novo production of K-alpha1 tubulin-specific antibodies: role in chronic lung allograft rejection.

Lung transplantation is the treatment option for a variety of end-stage pulmonary diseases. Posttransplant development of Abs against donor HLA and non-HLA Ags have been associated with acute and chronic rejection of transplanted organs. Development of bronchiolitis obliterans syndrome (BOS) following lung transplantation has been correlated with de novo production of anti-donor-HLA Abs. However, only a portion of the patients with BOS demonstrate detectable anti-donor-HLA Abs. Airway epithelium is considered as a major target for lung allograft rejection. In this study we demonstrate that many BOS(+) patients (12 of 36) develop Abs reactive to epithelial cell Ag that are distinct from HLA. Furthermore, de novo production of antiepithelial cell Ab precedes clinical onset of BOS. N-terminal sequencing and blastx analysis as well as blocking with K-alpha1 tubulin-specific Ab identified the epithelial Ag as K-alpha1 tubulin. Binding of the de novo-produced anti-K-alpha1 tubulin Abs to the airway epithelial cells resulted in the increased expression of transcription factors (TCF5 and c-Myc), leading to increased expression of fibrogenic growth factors, activation of cell cycle signaling, and fibroproliferation, the central events in immunopathogenesis of BOS following human lung transplantation.

Immunological link between primary graft dysfunction and chronic lung allograft rejection.

BACKGROUND: Primary graft dysfunction (PGD) in the immediate post-lung transplant period strongly increases the risk of chronic rejection (broncholitis obliterans syndrome). Here, we hypothesized that PGD-induced inflammation augments alloimmunity, thereby predisposing to broncholitis obliterans syndrome. METHODS: Primary graft dysfunction and broncholitis obliterans syndrome were diagnosed according to the established International Society for Heart and Lung Transplantation criteria. Anti-human leukocyte antigen (HLA) alloantibodies were analyzed using Flow-PRA. Donor HLA class II-specific T cells were analyzed using interferon (IFN)-gamma ELISPOT. Serum levels of 25 cytokines and chemokines were measured using LUMINEX. RESULTS: Of the 127 subjects, 29 (22.8%) had no PGD (grade 0), 42 (33.2%) had PGD-1, 36 (28.3%) had PGD-2, and 20 (15.7%) had PGD-3. Patients with PGD grades 1 to 3 (PGD(1-3)) had elevated proinflammatory mediators MCP-1, IP-10, interleukin (IL)-1 beta, IL-2, IFN-gamma, and IL-12 in the sera during the early posttransplant period compared with patients with PGD grade 0 (PGD(0)). On serial analysis, PGD(1-3) patients revealed increased development of de novo anti-HLA-II (5 years: 52.2% versus PGD(0) 13.5%, p = 0.008). However, no difference was found in anti-HLA-I alloantibody development (PGD(1-3) patients 48% versus PGD(0) 39.6%, p = 0.6). Furthermore, PGD(1-3) patients had increased frequency of donor HLA class II-specific CD4(+) T cells [(91.4 +/- 19.37) x 10(-6) versus (23.6 +/- 15.93) x 10(-6), p = 0.003]. CONCLUSIONS: Primary graft dysfunction induces proinflammatory cytokines that can upregulate donor HLA-II antigens on the allograft. Increased donor HLA-II expression along with PGD-induced allograft inflammation promotes the development of donor specific alloimmunity. This provides an important mechanistic link between early posttransplant lung allograft injury and reported association with broncholitis obliterans syndrome.

A randomized controlled trial of tacrolimus versus cyclosporine after lung transplantation.

BACKGROUND: The optimal maintenance immunosuppressive regimen after lung transplantation is uncertain. METHODS: We conducted a randomized controlled trial of tacrolimus versus cyclosporine in combination with azathioprine and prednisone after lung transplantation. Ninety adults were randomized to tacrolimus (n = 44) or cyclosporine (n = 46). The primary end point was a composite of a cumulative acute rejection A score of 3 or higher, a cumulative lymphocytic bronchitis B score of 4 or higher, or the onset of bronchiolitis obliterans syndrome (BOS) stage 0-p. RESULTS: Recipients randomized to cyclosporine were significantly more likely to develop the primary end point than those randomized to tacrolimus. During the study period, the primary end point developed in 39 of 46 cyclosporine subjects compared with 24 of 44 tacrolimus subjects (p = 0.002); acute rejection or lymphocytic bronchitis end points developed in 29 of 46 cyclosporine subjects compared with 18 of 44 tacrolimus subjects (p = 0.036). Furthermore, BOS stage 0-p was more likely to develop in the cyclosporine group than in the tacrolimus group, but this was not statistically significant (log-rank p = 0.1). In addition, there was a trend to a higher incidence of diabetes among those in the tacrolimus group, but there was no significant difference in graft survival or the total number of infections, or in the incidence of hypertension, chronic kidney disease, or cancer between the 2 groups. CONCLUSIONS: Tacrolimus is associated with a lower burden of acute rejection and lymphocytic bronchitis and a trend to a greater freedom from BOS stage 0-p than cyclosporine after lung transplantation.

Impact of immediate primary lung allograft dysfunction on bronchiolitis obliterans syndrome.

RATIONALE: Primary graft dysfunction is a common complication after lung transplantation and a significant risk factor for short- and long-term mortality. OBJECTIVE: We examined the impact of primary graft dysfunction on bronchiolitis obliterans syndrome. METHODS: We performed a retrospective cohort study of 334 adult lung transplant recipients at our program and graded the severity of primary graft dysfunction according to the International Society for Heart and Lung Transplantation definition. We evaluated the impact of primary graft dysfunction on acute rejection, lymphocytic bronchitis, and bronchiolitis obliterans syndrome stage 1, using univariable and multivariable Cox proportional hazards models. MAIN RESULTS: Among the 334 recipients, 65 did not have primary graft dysfunction (grade 0), 130 had grade 1, 69 had grade 2, and 70 had grade 3. In the univariable analysis, all grades of primary graft dysfunction were associated with a significantly increased risk of bronchiolitis obliterans syndrome stage 1 (grade 1: relative risk [RR] = 1.73; grade 2: RR = 2.13; and grade 3: RR = 2.53, compared with grade 0). The multivariable model demonstrated that the increased risk of bronchiolitis obliterans syndrome associated with primary graft dysfunction was independent of acute rejection, lymphocytic bronchitis, and community-acquired respiratory viral infections. However, there was no association between primary graft dysfunction and acute rejection or lymphocytic bronchitis. CONCLUSIONS: Primary graft dysfunction is associated with an increased risk of bronchiolitis obliterans syndrome independent of acute rejection, lymphocytic bronchitis, and community-acquired respiratory viral infections, and this risk is directly related to the severity of primary graft dysfunction.

Minimal acute rejection after lung transplantation: a risk for bronchiolitis obliterans syndrome.

Bronchiolitis obliterans syndrome (BOS) is a major cause of lung allograft dysfunction. Although previous studies have identified mild to severe rejection (grade>or=A2) as a risk factor for BOS, the role of minimal rejection (grade A1) remains unclear. To determine if A1 rejection by itself is a risk factor for BOS, we performed a retrospective cohort study on 228 adult lung transplant recipients over a 7-year period. Cohorts were defined by their most severe rejection episode (none, A1 only, and >or=A2) and analyzed for the subsequent development and progression of BOS using univariate and multivariate time-dependent Cox regression analysis. In the univariate model, the occurrence of isolated minimal rejection was a risk factor for all stages of BOS. Similarly, multivariate models that included HLA mismatch, cytomegalovirus pneumonitis, community acquired viral infection, underlying disease and type of transplant demonstrated that A1 rejection was a distinct risk factor for BOS. Furthermore, the associated risk with A1 rejection was slightly greater than the risk from >or=A2 and treatment of A1 rejection decreased the risk for subsequent BOS stage 1. We conclude that minimal rejection is associated with an increased risk for BOS development and progression that is comparable to A2 rejection.

A comparison of basiliximab and anti-thymocyte globulin as induction agents after lung transplantation.

BACKGROUND: Interleukin-2 receptor antagonists have supplanted polyclonal antibody preparations as the most frequently used induction agents after lung transplantation, but the relative efficacy of these agents has not been firmly established. METHODS: We retrospectively analyzed the efficacy of basiliximab compared with antithymocyte globulin among 157 adult lung transplant recipients at our center. RESULTS: At 3, 6, and 12 months after transplantation, the median cumulative acute rejection A scores for the basiliximab group (2, 2, and 3, respectively) were significantly higher than those for the anti-thymocyte globulin group (1, 1, and 2, respectively; p = 0.003, 0.004, and 0.033, respectively). In addition, basiliximab recipients were more likely to develop acute rejection grade > or = A2 than anti-thymocyte globulin recipients; in fact, 60% of basiliximab recipients compared with 38% of anti-thymocyte globulin recipients developed their first episode of acute rejection grade > or = A2 in the first 100 days after transplantation (log-rank p = 0.04). Furthermore, basiliximab recipients were more likely to develop bronchiolitis obliterans syndrome than anti-thymocyte globulin recipients (log-rank p = 0.036). Two years after transplantation, 36% of basiliximab recipients and 26% of anti-thymocyte globulin recipients developed bronchiolitis obliterans syndrome. However, there were no significant differences in the incidences of cytomegalovirus viremia and pneumonitis between the 2 groups (p = 0.86 and 0.89, respectively). CONCLUSIONS: Induction with anti-thymocyte globulin is associated with a lower burden of acute rejection and bronchiolitis obliterans syndrome compared with basiliximab, without a significant difference in the incidence of cytomegalovirus infections.