Tacrolimus versus cyclosporin as primary immunosuppression for lung transplant recipients.

BACKGROUND: Lung transplantation is a well-accepted treatment for people with most end-stage lung diseases. Although both tacrolimus and cyclosporin are used as primary immunosuppressive agents in lung transplant recipients, it is unclear which of these drugs is better in reducing rejection and death without causing adverse effects. OBJECTIVES: To assess the benefits and harms of tacrolimus versus cyclosporin for primary immunosuppression in lung transplant recipients. SEARCH METHODS: We searched the Cochrane Renal Group's Specialised Register to 10 April 2013 through contact with the Trials Search Co-ordinator using search terms relevant to this review. We also searched Science Citation Index Expanded and the Transplant Library to 20 April 2013. SELECTION CRITERIA: We included all randomised controlled trials (RCT) that compared any dose and duration of administration of tacrolimus versus cyclosporin as primary immunosuppressive treatment in lung transplant recipients. Our selection criteria required that all included patients received the same additional immunosuppressive therapy within each study. DATA COLLECTION AND ANALYSIS: Three authors extracted data. For dichotomous data we used risk ratio (RR) and used mean difference (MD) for continuous data, each with 95% confidence intervals (CI). Methodological components of the included studies were used to assess risk of systematic errors (bias). Trial sequential analysis was used to assess risk of random errors (play of chance). MAIN RESULTS: We included three studies that enrolled a total of 413 adult patients that compared tacrolimus with microemulsion or oral solution cyclosporin. All studies were found to be at high risk of bias. Tacrolimus seemed to be significantly superior to cyclosporin regarding the incidence of bronchiolitis obliterans syndrome (RR 0.46, 95% CI 0.29 to 0.74), lymphocytic bronchitis score (MD -0.60, 95% CI -1.04 to -0.16), treatment withdrawal (RR 0.27, 95% CI 0.16 to 0.46), and arterial hypertension (RR 0.67, 95% CI 0.50 to 0.89). However, the finding for arterial hypertension was not confirmed when analysed using a random-effects model (RR 0.54, 95% CI 0.17 to 1.73). Furthermore, trial sequential analysis found that none of the meta-analyses reached the required information sizes and cumulative Z-curves did not cross trial sequential monitoring boundaries. Diabetes mellitus occurred more frequently among people in the tacrolimus group compared with the cyclosporin group when the fixed-effect model was applied (RR 4.24, 95% CI 1.58 to 11.40), but no difference was found when the random-effects model was used for analysis (RR 4.43, 95% CI 0.75 to 26.05). Again, trial sequential analysis found that the required information threshold was not reached and cumulative Z-curve did not cross the trial sequential monitoring boundary. No significant difference between treatment groups was observed regarding mortality (RR 1.06, 95% CI 0.75 to 1.49), incidence of acute rejection (RR 0.89, 95% CI 0.77 to 1.03), numbers of infections/100 patient-days (MD -0.15, 95% CI -0.30 to 0.00), cancer (RR 0.21, 95% CI 0.04 to 1.16), kidney dysfunction (RR 1.41, 95% CI 0.93 to 2.14), kidney failure (RR 1.57, 95% CI 0.28 to 8.94), neurotoxicity (RR 7.06, 95% CI 0.37 to 135.19), and hyperlipidaemia (RR 0.60, 95% CI 0.30 to 1.20). Trial sequential analysis showed the required information thresholds were not reached for any of these outcome measures. AUTHORS' CONCLUSIONS: Tacrolimus may be superior to cyclosporin regarding bronchiolitis obliterans syndrome, lymphocytic bronchitis, treatment withdrawal, and arterial hypertension, but may be inferior regarding development of diabetes. No difference in mortality and acute rejection was observed between patients treated with tacrolimus and cyclosporin. There were few studies comparing tacrolimus and cyclosporin after lung transplantation, and the numbers of patients and events in the included studies were limited. Furthermore, the included studies were deemed to be at high risk of bias. Hence, more RCTs are needed to assess the results of the present review. Such studies ought to be conducted with low risks of systematic errors (bias) and of random errors (play of chance).

Detection of Epstein-Barr virus-specific memory CD4+ T cells using a peptide-based cultured enzyme-linked immunospot assay.

Approaches to evaluate T-cell responses to Epstein-Barr virus (EBV) include enzyme-linked immunospot (ELISPOT), which quantifies cells capable of immediate interferon-γ secretion upon antigen stimulation. However, evaluation of expandable EBV-specific memory T cells in an ELISPOT format has not been described previously. We quantified EBV-specific T-cell precursors with high proliferative capacity by using a peptide-based cultured interferon-γ ELISPOT assay. Standard and cultured ELISPOT responses to overlapping peptide pools (15-mers overlapping by 11 amino acids) covering the lytic (BZLF1 and BMRF1) and latent (EBNA1, EBNA3a, EBNA3b, EBNA3c, LMP1 and LMP2) EBV proteins were evaluated in 20 healthy subjects with remote EBV infection and, for comparison, in four solid organ transplant recipients. Cultured ELISPOT responses to both lytic and latent EBV antigens were significantly higher than standard ELISPOT responses. The distribution of EBV-specific T-cell responses detected in healthy virus carriers showed more consistent cultured ELISPOT responses compared with standard ELISPOT responses. T-cell responses quantified by cultured ELISPOT were mainly mediated by CD4+ T cells and a marked pattern of immunodominance to latent-phase antigens (EBNA1 > EBNA3 family antigens > LMP2 > LMP1) was shown. Both the magnitude and distribution of EBV-specific T-cell responses were altered in solid organ transplant recipients; in particular, cultured ELISPOT responses were almost undetectable in a lung-transplanted patient with EBV-associated diseases. Analysis of T-cell responses to EBV by ELISPOT assays might provide new insights into the pathogenesis of EBV-related diseases and serve as new tools in the monitoring of EBV infection in immunocompromised patients.

Human leucocyte antigen-defined microchimerism early post-transplant does not predict for stable lung allograft function.

Microchimerism is the presence of foreign cells in an individual below 1% of total cells, which can occur in the setting of solid organ transplantation. This study quantitated donor-derived cellular subsets longitudinally in human leucocyte antigen (HLA)-mismatched lung transplant recipients (LTR) during the first post-operative year and evaluated the pattern of peripheral microchimerism with clinical outcomes. Peripheral blood mononuclear cells (PBMC) isolated from non-HLA-B44 LTR who received HLA-B44 allografts were sorted flow cytometrically into three cellular subsets. Real-time quantitative polymerase chain reaction (q-PCR) demonstrated that donor-derived HLA-B44 microchimerism is a common phenomenon, observed in 61% of patients. The level of donor-derived cells varied across time and between LTR with frequencies of 38% in the B cells/monocytes subset, 56% in the T/NK cells subset and 11% in the dendritic cells (DC) subset. Observations highlighted that microchimerism was not necessarily associated with favourable clinical outcomes in the first year post-lung transplantation.

Cytokine complex-expanded natural killer cells improve allogeneic lung transplant function via depletion of donor dendritic cells.

RATIONALE: Natural killer (NK) cells are innate lymphocytes that target virus-infected and tumor cells. Much less is known about their ability to limit adaptive immune responses. OBJECTIVES: Thus, we investigated to what extent NK cells can influence mouse lung allograft rejection. METHODS: For this purpose, we employed an orthotopic lung transplantation model in mice. MEASUREMENTS AND MAIN RESULTS: We demonstrate here that NK cells infiltrate mouse lung allografts before T cells and thereby diminished allograft inflammation, and that NK-cell deficiency enhanced allograft rejection. In contrast, expansion of recipient NK cells through IL-15/IL-15Rα complex treatment resulted in decreased T-cell infiltration and alloreactive T-cell priming as well as improved function of the allogeneic lung transplant. Only perforin-competent, but not perforin-deficient, NK cells were able to transfer these beneficial effects into transplanted NK cell-deficient IL-15Rα(-/-) mice. These NK cells killed allogeneic dendritic cells (DCs) in vitro and significantly decreased the number of allogeneic DCs in transplanted lungs in vivo. Furthermore, DC-depleted lung allografts presented decreased signs of rejection. CONCLUSIONS: These results suggest that NK cells favor allograft acceptance by depleting donor-derived DCs, which otherwise would prime alloreactive T-cell responses. Thus, conditioning regimens that augment NK-cell reactivity should be clinically explored to prepare lung allograft recipients.

Potential of targeting TGF-ß for organ transplant patients.

TGF-ß was originally considered as an immunoregulatory cytokine, but accumulating data demonstrate that it also plays a critical role in development of effector immunity. Since TGF- ß has a potent ability to alter immune responses, modulation of the TGF-ß pathway for treatment of transplantation patients could be effective if carried out in a target selective manner. This review will focus on the role of TGF-ß in T cell differentiation and discuss the prospect of TGF-ß as the therapeutic target of lung transplantation acceptance.

Pathologic findings in lung allografts with anti-HLA antibodies.

BACKGROUND: Despite data indicating a positive correlation between donor-specific anti-HLA antibodies (DSAs) and early development of bronchiolitis obliterans syndrome (BOS) in lung allografts, the role of an antibody-mediated process in acute and chronic lung allograft rejection has not been elucidated. In this study we evaluated pathologic features of transplant lung biopsies in patients with and without DSAs. METHODS: Forty-one lung transplant biopsies from 41 patients at our institution were included in our study. The biopsy H&E slides were reviewed in a blinded fashion, and scored for presence of microvascular inflammation, acute rejection, bronchiolar inflammation and acute lung injury, as well as diffuse alveolar damage (DAD). Microvascular inflammation was graded by the presence of capillary neutrophils on a scale of 0 to 4(+). For immunohistochemical analysis, the pattern and intensity of staining for C4d and C3d deposition were evaluated in airways and alveolar capillaries. RESULTS: Histopathology suspicious for antibody-mediated rejection (AMR)-defined as≥2(+) neutrophilic infiltration and/or DAD-were more common in DSA-positive cases than controls (11 of 16 vs 6 of 25, p<0.01). Evidence of allograft dysfunction was significantly more common among patients with both DSA and suspicious histopathology compared with controls (5 of 10 vs 3 of 25, p = 0.03). The combination of DSAs and histopathology suspicious for AMR was associated with both BOS (p = 0.002) and mortality (p = 0.03). Immunohistochemistry for C3d and C4d showed no correlation with each other, DSAs or histopathology. CONCLUSIONS: Grade 2(+) neutrophilic infiltration is the histopathologic finding most closely related to DSAs with graft dysfunction and development of BOS in lung transplant recipients and may be a marker for AMR.

Donor-specific antibodies are associated with antibody-mediated rejection, acute cellular rejection, bronchiolitis obliterans syndrome, and cystic fibrosis after lung transplantation.

BACKGROUND: Lung transplantation is limited by chronic lung allograft dysfunction. Acute cellular rejection (ACR) is a risk factor for allograft dysfunction; however, the role of antibody-mediated rejection (AMR) is not well characterized. METHODS: This was a retrospective review from 2007 to 2011 of lung transplant recipients with human leukocyte antigen (HLA) antibody testing using Luminex (Luminex Corp, Austin, TX) single-antigen beads. Statistics included Fisher's exact test for significance. RESULTS: Donor-specific antibodies (DSA) developed in 13 of 44 patients. Of the 13 with DSA, 12 had cystic fibrosis compared with 18 of 31 in the non-DSA group (p = 0.035). Of those with DSAs, 23.1% occurred within the first year, and 69.2% occurred between 1 and 3 years. Twelve of 13 DSA patients had anti-HLA DQ specificity compared with 2 of 31 non-DSA patients (p = 0.0007). AMR developed in 10 of the 13 DSA patients compared with 1 of 31 non-DSA patients (p = 0.0001). The DSA group experienced 2.6 episodes/patient of cellular rejection vs 1.7 episodes/patient in the non-DSA group (p = 0.059). Bronchiolitis obliterans syndrome developed in 11 of 13 in the DSA group vs 10 of 31 in the non-DSA group (p = 0.0024). In the DSA group, 11.5% HLAs matched compared with 20.4% in the non-DSA group (p = 0.093). AMR developed in 11 of 22 patients in the non-DSA HLA group compared with 0 of 22 in the group without non-DSA HLA antibodies (p = 0.002). Survival at 1 and 3 years was 92% and 36% in the DSA group, respectively, and 97% and 65% in the non-DSA group. CONCLUSIONS: DSAs and non-DSAs occur frequently after lung transplantation. DSAs are prevalent in the cystic fibrosis population and are associated with AMR, bronchiolitis obliterans syndrome, and possibly, ACR.

Study of B-cell subpopulations in lung transplant recipients with posttransplant infection.

BACKGROUND: Posttransplant infection after lung transplantation is a common feature due to the immunodeficiency induced by the immunosuppressive load. AIM: To assess B-cell subsets in lung transplant recipients suffering at least one episode of infection within the first year posttransplantation. METHODS: Twenty-eight lung transplant recipients were enrolled in the study. Their overall mean age was 56.6 ± 10.7 years and 10 were women (35.7%). All recipients were treated with steroids, tacrolimus, and mycophenolate mofetil. B-cell subset levels were measured in peripheral blood before as well as 7, 14, 30, 60, 90, and 180 days posttransplantation. RESULTS: No difference in the absolute number of B-cell subsets was observed within the first year of follow-up. However, pre-germinal center-activated naïve B cells (Bm2'), defined as IgD(+)CD38(++), were increased among patients displaying infections within the first year. The increased Bm2' subset was accompanied by a decrease in the double negative (CD27(-)IgD(-)) B-cell population. CONCLUSION: Infections in lung transplant recipients were associated with an increase in the Bm2' subset even before transplantation. It is possible that Bm2' cells have a role in response to infection in lung transplantation.

Usefulness of immune monitoring in lung transplantation using adenosine triphosphate production in activated lymphocytes.

BACKGROUND: The ImmuKnow (Cylex Inc, Columbia, MD) assay measures the amount of adenosine triphosphate (ATP) produced by helper CD4(+) cells after stimulation with a T-cell mitogen. We hypothesized that this assay can be used to assess the immune function of lung transplant recipients and identify those at risk of developing acute cellular rejection and respiratory infection. METHODS: Lung transplant recipients at University of California Los Angeles between January 1, 2006 and December 31, 2009 received a bronchoscopy with broncheoalveolar lavage, transbronchial biopsy and ImmuKnow values drawn at regular intervals as well as during episodes of clinical deterioration. The recipient's clinical condition at each time-point was classified as healthy, acute cellular rejection, or respiratory infection. Mixed-effects models were used to compare the ATP levels among these groups, and odds ratios for rejection and infection were calculated. RESULTS: The mean ATP level was 431 ± 189 ng/ml for the rejection group vs 377 ± 187 ng/ml for the healthy group (p = 0.10). A recipient with an ATP level > 525 ng/ml was 2.1 times more likely to have acute cellular rejection (95% confidence interval [CI] 1.1-3.8). Similarly, the mean ATP level was 323 ± 169 ng/ml for the infection group vs 377 ± 187 ng/ml for the healthy group (p = 0.03). A recipient with an ATP level < 225 ng/ml was 1.9 times more likely to have respiratory infection (95% CI, 1.1-3.3). However, the test was associated with poor performance characteristics. It had low sensitivity, specificity with an area under the receiver operating characteristic curve of only 0.61 to diagnose rejection and 0.59 to diagnose infection. CONCLUSIONS: The ImmuKnow assay appears to have some ability to assess the overall immune function of lung transplant recipients. However, this study does not support its use as a reliable predictor of episodes of acute cellular rejection or respiratory infection.

Antibody-mediated rejection in a lung transplant recipient after acute stroke.

Antibody-mediated rejection (AMR) is becoming a more recognized problem in lung transplantation. We present a case of late onset AMR in a lung transplant recipient after an acute embolic stroke requiring thrombolytic therapy, who previously had a completely unremarkable course for over 3 years.

The bone marrow functions as the central site of proliferation for long-lived NK cells.

NK cells play an important role in the early defense against invading pathogens. Although it is well established that infection leads to a substantial, local increase in NK cell numbers, little is known about the mechanisms that trigger their proliferation and migration. In this study, we investigated the dynamics of NK cell responses after intranasal respiratory virus infection. We show that NK cell numbers increased in the airways after influenza virus infection but find no evidence of proliferation either at the site of infection or in the draining lymph nodes. Instead, we find that the bone marrow (BM) is the primary site of proliferation of both immature and mature NK cells during infection. Using an adoptive transfer model, we demonstrate that peripheral, long-lived and phenotypically mature NK cells migrate back to the BM and proliferate there, both homeostatically and in response to infection. Thus, the BM is not only a site of NK cell development but also an important site for proliferation of long-lived mature NK cells.

Immunology mini-review: the basics of T(H)17 and interleukin-6 in transplantation.

The outcomes of organ transplantation are determined by graft rejection, the mechanisms of which are some of the most important areas of study in the transplantation field. The main cause of rejection is the immunologic response of the recipient toward the transplanted organ. The immunologic responses are regulated by T-cell subsets, especially helper T-cells, which have been characterized as T(H)1 or T(H)2 cells according to their profiles of cytokines production. A unique subset of recently identified lymphocytes, the regulatory T cells (T(reg)s), seem to play a role in tolerance. The recently identified T(H)17 cells are a subset of effector-helper lymphocytes that specifically secrete interleukin (IL) 17. Interestingly, T(H)17 and T(reg) both develop from naïve T cells on stimulation by transforming growth factor ß. The difference is only the existence of IL-6, a proinflammatory cytokine. T(H)17 clears pathogens that are not adequately handled by T(H)1 and T(H)2 elements, as well as contributing to autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, and inflammatory diseases. Autoimmune diseases are caused by reactions to self-antigens. T(H)17 (or IL-17) and IL-6 are also thought to be involved in rejection after organ transplantation. We examined the contributions of T(H)17 and IL-6 in bronchiolitis obliterans (BO), the histologic finding in chronic rejection of lung transplantations. Earlier studies have reported that T(H)17 and IL-6 contribute not only to chronic rejection of lung transplantations, but also to the rejection of other solid organs, e.g., heart, liver, and kidney. In addition, prospective avenues of research on T(H)17 and IL-6 in transplantation have emerged from the perspectives of recent studies.

Posterior reversible encephalopathy syndrome due to immunosuppressant after living-donor lobar lung transplantation: report of a case.

Living-donor lobar lung transplantation was performed in a 10-year-old boy with bronchiolitis obliterans after bone marrow transplantation for recurrent acute myeloid leukemia. He developed posterior reversible encephalopathy syndrome (PRES) due to calcineurin inhibitor (CNI) postoperatively, which was recovered with suspension of CNI. PRES should be considered one of the important morbidity after lung transplantation.

Lung transplant acceptance is facilitated by early events in the graft and is associated with lymphoid neogenesis.

Early immune responses are important in shaping long-term outcomes of human lung transplants. To examine the role of early immune responses in lung rejection and acceptance, we developed a method to retransplant mouse lungs. Retransplantation into T-cell-deficient hosts showed that for lungs and hearts alloimmune responses occurring within 72 h of transplantation are reversible. In contrast to hearts, a 72-h period of immunosuppression with costimulation blockade in primary allogeneic recipients suffices to prevent rejection of lungs upon retransplantation into untreated allogeneic hosts. Long-term lung acceptance is associated with induction of bronchus-associated lymphoid tissue, where Foxp3(+) cells accumulate and recipient T cells interact with CD11c(+) dendritic cells. Acceptance of retransplanted lung allografts is abrogated by treatment of immunosuppressed primary recipients with anti-CD25 antibodies. Thus, events contributing to lung transplant acceptance are established early in the graft and induction of bronchus-associated lymphoid tissue can be associated with an immune quiescent state.

Pulmonary immune changes early after laparoscopic antireflux surgery in lung transplant patients with gastroesophageal reflux disease.

BACKGROUND: The biologic mechanisms by which laparoscopic antireflux surgery (LARS) might influence the inflammatory process leading to bronchiolitis obliterans syndrome are unknown. We hypothesized that LARS alters the pulmonary immune profile in lung transplant patients with gastroesophageal reflux disease. METHODS: In 8 lung transplant patients with gastroesophageal reflux disease, we quantified and compared the pulmonary leukocyte differential and the concentration of inflammatory mediators in the bronchoalveolar lavage fluid (BALF) 4 weeks before LARS, 4 weeks after LARS, and 12 months after lung transplantation. Freedom from bronchiolitis obliterans syndrome (graded 1-3 according to the International Society of Heart and Lung Transplantation guidelines), forced expiratory volume in 1 second trends, and survival were also examined. RESULTS: At 4 weeks after LARS, the percentages of neutrophils and lymphocytes in the BALF were reduced (from 6.6% to 2.8%, P = 0.049, and from 10.4% to 2.4%, P = 0.163, respectively). The percentage of macrophages increased (from 74.8% to 94.6%, P = 0.077). Finally, the BALF concentration of myeloperoxide and interleukin-1ß tended to decrease (from 2109 to 1033 U/mg, P = 0.063, and from 4.1 to 0 pg/mg protein, P = 0.031, respectively), and the concentrations of interleukin-13 and interferon-γ tended to increase (from 7.6 to 30.4 pg/mg protein, P = 0.078 and from 0 to 159.5 pg/mg protein, P = 0.031, respectively). These trends were typically similar at 12 months after transplantation. At a mean follow-up of 19.7 months, the survival rate was 75% and the freedom from bronchiolitis obliterans syndrome was 75%. Overall, the forced expiratory volume in 1 second remained stable during the first year after transplantation. CONCLUSIONS: Our preliminary study has demonstrated that LARS can restore the physiologic balance of pulmonary leukocyte populations and that the BALF concentration of pro-inflammatory mediators is altered early after LARS. These results suggest that LARS could modulate the pulmonary inflammatory milieu in lung transplant patients with gastroesophageal reflux disease.

Preoperative recipient cytokine levels are associated with early lung allograft dysfunction.

BACKGROUND: Primary graft dysfunction (PGD) is a morbid complication after lung transplant (LTx). Recipient before and after cytokine and chemokine profiles may be associated with a recipient's propensity to have PGD. METHODS: Serum samples were obtained from adult (more than 17 years old) primary LTx recipients (2002 to 2007) at two time points: (1) pre-reperfusion of transplanted lungs, and (2) within 24 hours after reperfusion. Interleukin (IL)-6, IL-8, IL-10, chemokine ligand (CCL)-2, and matrix metalloproteinase (MMP)-9 levels were determined. A PaO2/FiO2 ratio less than 300 at 48 hours (International Society for Heart and Lung Transplantation PGD grade 2 or more) was used to stratify patients. Follow-up was obtained through August 2009. Cytokine levels at both time points and the change in levels were assessed for association with PGD grade 2 or more. Outcomes and clinical characteristics were analyzed. RESULTS: Of 28 patients, 8 (28.6%) had PGD grade 2 or more. Median follow-up was 23 months (interquartile range, 16 to 31). Demographics, clinical data, and pre-LTx diagnoses did not differ between the groups. Patients who had PGD grade 2 or more had higher baseline levels of IL-10, IL-8, IL-6, and CCL-2 (all p<0.05). Within 24 hours, PGD grade 2 or more patients had higher IL-10 (p=0.02) and CCL-2 (p=0.04) levels. The PGD grade 2 or more patients were more likely to have had cardiopulmonary bypass during LTx (p=0.002) and blood products administered: platelets (p=0.004), plasma (p=0.05), and packed red blood cells (p=0.03)]. The PGD grade 2 or more patients had longer length of stay, duration of mechanical ventilation, and total intensive care unit days. CONCLUSIONS: Higher before and after transplant cytokine/chemokine levels were found in LTx recipients who subsequently had PGD grade 2 or more. Our study demonstrates that the recipient's inflammatory state at the time of LTx may impact early allograft function. That could represent a potential target for pretransplant pharmacologic intervention.

1,25-Dihydroxycholecalciferol with low-calcium diet reduces acute rejection in rat lung allotransplantation.

OBJECTIVES: The effect of 1,25-dihydroxycholecalciferol (calcitriol, vitamin D3) with a low-calcium diet on the acute lung allograft rejection in a rat unilateral left lung transplantation model was evaluated. METHODS: Three transplantation groups were studied (n = 5, male Brown-Norway to Fischer F344, 235 ± 15 g body weight): calcitriol and low-calcium diet, low-calcium diet and normal diet. Calcitriol (4 µg/kg/day) was injected intraperitoneally for 5 days, starting from the day of transplantation. In addition, two non-transplantation groups were compared: (n = 3, Brown-Norway) to measure the level of cytokines, and Fischer F344 receiving calcitriol and a low-calcium diet to measure the serum calcium level. The recipients of transplantation were killed on Day 5 post-transplant. The contralateral right main bronchus and the pulmonary artery were occluded for 5 min and blood was drawn for the blood gas analysis, and the grafts were assessed for histology (International Society for Heart and Lung Transplantation 1996/rank scale). Lung levels of interleukin (IL)-2, IL-6, IL-12 and tumour necrosis factor-α (TNF-α) were assessed within the calcitriol and low-calcium diet, low-calcium diet and Brown-Norway groups. The serum calcium level was assessed in the Fischer F344 group. An analysis of variance with Tukey's post hoc test was used to compare the arterial blood oxygen pressure and the lung cytokine expression between groups. A non-parametric Kruskal-Wallis test followed by the Siegel and Castellan post hoc test was used to assess the differences between the groups according to the lung graft rejection grading. Student's paired t-test was used to compare the serum calcium level. RESULTS: The arterial PaO(2) was significantly higher in the calcitriol and the low-calcium diet groups when compared with low-calcium diet or normal diet groups (356 ± 72 mmHg; P < 0.05 vs other groups). The arterial and bronchial rejection observed in calcitriol and low-calcium diet group was significantly milder than in the low-calcium diet or normal diet groups (A1-2, B1-2; P < 0.05 vs other groups). IL-2 and IL-6 levels were significantly higher in low-calcium diet vs calcitriol and low-calcium diet and Brown-Norway groups. IL-12 and TNF-α did not differ among the groups. There was no significant difference in serum calcium level before and after the treatment in the Fischer F344 group. CONCLUSIONS: Calcitriol with a low-calcium diet treatment improves lung function, reduces lung allograft acute rejection, decreases IL-2 and IL-6 allograft expression and does not change the serum calcium level significantly.

The histopathology of lung allograft dysfunction associated with the development of donor-specific HLA alloantibodies.

The histopathology of antibody-mediated rejection in lung allografts, outside of classical hyperacute rejection, has been poorly defined, in part because of the difficulty in identifying potential alloantibodies and in separating alloreactive and nonspecific complement-mediated reactions. In this study, we looked at lung biopsies coinciding with the development of anti-human leukocyte antigen (anti-HLA) antibodies and lung dysfunction in a diverse group of lung transplant recipients over a 3-year period. We identified 23 patients and found that 17 had coexistent high-grade acute cellular rejection, 5 had patchy acute lung injury, and 1 had bronchiolitis at the time that anti-HLA alloantibodies appeared. Capillaritis was seen in 4/22 (18%) cases, usually in the context of cellular rejection. When the 17 cases of acute cellular rejection with coexistent anti-HLA antibodies were compared with a matched group of 26 patients with equivalent cellular rejection grade without anti-HLA antibodies, the only morphologic feature that separated the 2 groups was capillaritis seen in a minority of cases. C4d deposits were seen in both groups, although more frequently in those cases with anti-HLA antibodies (76% vs. 24%). The development of anti-HLA alloantibodies often occurs in the setting of acute cellular rejection, which in only a minority of cases can be identified as likely having an antibody-mediated component. C4d staining does not consistently separate the 2 groups. Identifying and ascribing allograft dysfunction to antibody-mediated rejection related to the development of anti-HLA antibodies is a difficult task that cannot be solved exclusively by morphology and requires significant clinicopathologic correlation.

High cumulative dose exposure to voriconazole is associated with cutaneous squamous cell carcinoma in lung transplant recipients.

BACKGROUND: Lung transplant recipients (LTR) have an increased risk of cutaneous squamous cell carcinoma (SCC) due to immunosuppressive therapy. Voriconazole, which is associated with phototoxic side effects in some patients, may be an additional risk factor for SCC in this population. METHODS: To test whether voriconazole is a risk factor for developing SCC in LTR, we evaluated cumulative exposure to voriconazole in 327 adults who underwent lung transplantation at one center between 1991 and 2010. Voriconazole exposure was assessed as a time-varying covariate. We used survival analysis methods to assess the risk of developing SCC over time. RESULTS: Exposure to voriconazole was associated with a 2.6-fold increased risk for SCC. This phenomenon was dose-dependent: the risk for SCC increased by 5.6% with each 60-day exposure at a standard dose of 200 mg twice daily. At 5 years after transplant, voriconazole conferred an absolute risk increase for SCC of 28%. CONCLUSIONS: These results suggest that caution should be taken when using voriconazole in LTR because this drug increases the already high risk for SCC in this population.