Fibrotic progression from acute cellular rejection is dependent on secondary lymphoid organs in a mouse model of chronic lung allograft dysfunction.

Chronic lung allograft dysfunction (CLAD) remains one of the major limitations to long-term survival after lung transplantation. We modified a murine model of CLAD and transplanted left lungs from BALB/c donors into B6 recipients that were treated with intermittent cyclosporine and methylprednisolone postoperatively. In this model, the lung allograft developed acute cellular rejection on day 15 which, by day 30 after transplantation, progressed to severe pleural and peribronchovascular fibrosis, reminiscent of changes observed in restrictive allograft syndrome. Lung transplantation into splenectomized B6 alymphoplastic (aly/aly) or splenectomized B6 lymphotoxin-ß receptor-deficient mice demonstrated that recipient secondary lymphoid organs, such as spleen and lymph nodes, are necessary for progression from acute cellular rejection to allograft fibrosis in this model. Our work uncovered a critical role for recipient secondary lymphoid organs in the development of CLAD after pulmonary transplantation and may provide mechanistic insights into the pathogenesis of this complication.

Evaluation of Bone Mineral Density in Lung Transplant Recipients by Chest Computed Tomography.

INTRODUCTION: Lung transplantation (LT) recipients are at risk of bone mineral density (BMD) loss. Pre- and post-LT BMD loss has been reported in some cross-sectional studies; however, there are limited studies regarding the serial BMD change in LT recipients. The aim of this study was to investigate the serial BMD changes and the clinical characteristics associated with BMD decline. METHODS: This was a single-center, retrospective observational study. BMD was serially measured in thoracic vertebral bodies (Th4, 7, 10) using computed tomography (CT) before and 3 and 12 months after LT. The frequency of osteoporosis and factors associated with pre-LT osteoporosis and post-LT BMD loss were evaluated. The frequency of post-LT compression fracture and its associated factors were also analyzed. RESULTS: This study included 128 adult LT recipients. LT recipients had decreased BMD (151.8 ± 42.2 mg/mL) before LT compared with age-, sex-, and smoking index-matched controls (176.2 ± 35.7 mg/mL). The diagnosis of COPD was associated with pre-LT osteoporosis. LT recipients experience further BMD decline after transplantation, and the percentage of recipients classified as exhibiting osteoporosis increased from 20% at baseline to 43% at 12 months. Recipients who had been taking no or small doses of glucocorticoids before LT had rapid BMD loss after LT. Early bisphosphonate use (within 3 months) after LT attenuated BMD loss and decreased new-onset compression fracture. CONCLUSION: LT recipients are at high risk for BMD loss and compression fracture after LT. Early bisphosphonate use may decrease BMD loss and compression fracture.

Comparison of the safety and cost-effectiveness of nebulized liposomal amphotericin B and amphotericin B deoxycholate for antifungal prophylaxis after lung transplantation.

INTRODUCTION: Fungal infection after lung transplantation can lead to poor clinical outcome, for which lung transplant recipients require prophylaxis. One of the antifungal agents used after lung transplantation is nebulized amphotericin B (AMB). Nebulized AMB causes adverse events such as dyspnea and airway irritation, and long-term use leads to high economic costs. So far, prophylactic regimens employing AMB deoxycholate (AMB-d) and liposomal AMB (L-AMB) have been developed. This study compared the efficacy, safety, and cost of AMB-d and L-AMB. PATIENTS AND METHODS: Patients who underwent lung transplantation at Kyoto University Hospital from January 2021 to May 2023 were included in this study. Thirty-three patients received nebulized AMB-d, whereas 29 received nebulized L-AMB. RESULTS: Both regimens maintained comparable prophylactic efficacy regarding the development of fungal infection in the AMB-d and L-AMB groups (3.0% vs. 3.4%, P = 0.877). Patients treated with nebulized L-AMB experienced fewer respiratory-related adverse reactions than those treated with nebulized AMB-d (6.9% vs. 30.3%, P < 0.05), leading to a longer treatment duration with L-AMB than with AMB-d. Additionally, the daily cost of administering L-AMB was lower than that of administering AMB-d (3609 Japanese yen vs. 1792.3 Japanese yen, P < 0.05). DISCUSSION: These results suggest that nebulized L-AMB is safer and more cost-effective than nebulized AMB-d, with comparable efficacy.

Impact of perioperative airway pathogens on living-donor lobar lung transplantation outcomes.

PURPOSE: To elucidate the clinical impact of pathogenic organism (PO) positivity early after transplantation, we evaluated the impact of perioperative airway POs on outcomes after living-donor lobar lung transplantation (LDLLT), where the graft airway is supposed to be sterile from a healthy donor. METHOD: A retrospective review of 67 adult LDLLT procedures involving 132 living donors was performed. Presence of POs in the recipients' airways was evaluated preoperatively and postoperatively in intensive-care units. RESULTS: POs were detected preoperatively in 13 (19.4%) recipients. No POs were isolated from the donor airways at transplantation. POs were detected in 39 (58.2%) recipients postoperatively; most were different from the POs isolated preoperatively. Postoperative PO isolation was not associated with short-term outcomes other than prolonged postoperative ventilation. The 5-year overall survival was significantly better in the PO-negative group than in the PO-positive group (89.1% vs. 63.7%, P = 0.014). In the multivariate analysis, advanced age (hazard ratio [HR]: 1.041 per 1-year increase, P = 0.033) and posttransplant PO positivity in the airway (HR: 3.684, P = 0.019) significantly affected the survival. CONCLUSIONS: The airways of the living-donor grafts were microbiologically sterile. PO positivity in the airway early after transplantation negatively impacted long-term outcomes.

M2-like tumor-associated macrophages promote epithelial-mesenchymal transition through the transforming growth factor ß/Smad/zinc finger e-box binding homeobox pathway with increased metastatic potential and tumor cell proliferation in lung squamous cell carcinoma.

Epithelial-mesenchymal transition (EMT) promotes primary tumor progression toward a metastatic state. The role of tumor-associated macrophages (TAMs) in inducing EMT in lung squamous cell carcinoma (LUSC) remains unclear. We aimed to clarify the significance of TAMs in relation to EMT in LUSC. We collected 221 LUSC specimens from patients who had undergone surgery. Immunohistochemistry was performed to evaluate M1-like and M2-like TAM distribution and EMT by E-cadherin and vimentin staining. Human LUSC cell lines (H226 and EBC-1) and a human monocyte cell line (THP-1) were used for in vitro experiments. M2-like polarization of TAMs and EMT marker expression in LUSC cells were evaluated by western blotting. The biological behavior of LUSC cells was evaluated by migration, invasion, and cell proliferation assays. Immunohistochemical analysis showed that 166 (75.1%) tumors were E-cadherin-positive and 44 (19.9%) were vimentin-positive. M2-like TAM density in the tumor stroma was significantly associated with vimentin positivity and worse overall survival. Western blotting demonstrated higher levels of CD163, CD206, vascular endothelial growth factor, and transforming growth factor beta 1 (TGF-ß1) in TAMs versus unstimulated macrophages. Furthermore, increased TGF-ß1 secretion from TAMs was confirmed by ELISA. TAM-co-cultured H226 and EBC-1 cells exhibited EMT (decreased E-cadherin, increased vimentin). Regarding EMT-activating transcriptional factors, phosphorylated Smad3 and ZEB-family proteins were higher in TAM-co-cultured LUSC cells than in parental cells. TAM-co-cultured H226 and EBC-1 cells demonstrated enhanced migration and invasion capabilities and improved proliferation. Overall, the present study suggests that TAMs can induce EMT with increased metastatic potential and tumor cell proliferation in LUSC.

The first successful case of ABO-incompatible living-donor lobar lung transplantation following desensitization therapy.

ABO-incompatible (ABO-I) living-donor lobar lung transplantation (LDLLT) was successfully performed in a 14-year-old girl who suffered from bronchiolitis obliterans due to graft-versus-host disease following hematopoietic stem cell transplantation. In the ABO-I LDLLT procedure, the blood type O patient received a right lower lobe donated from her blood type B father and a left lower lobe donated from her blood type O mother. Desensitization therapy, using rituximab, immunosuppressants, and plasmapheresis, was implemented for 3 weeks prior to transplantation to reduce the production of anti-B antibodies in the recipient and prevent acute antibody-mediated rejection after ABO-I LDLLT.

Trough ganciclovir concentration as predictor of leukopenia in lung transplant recipients receiving valganciclovir prophylaxis.

BACKGROUND: Valganciclovir is the first-line agent for Cytomegalovirus prophylaxis after lung transplantation. However, its use is associated with a relatively high risk of hematological toxicity. This study aimed to investigate the relationship between trough ganciclovir concentration and hematologic toxicity in lung transplantation patients receiving valganciclovir prophylaxis, and identify factors that affect ganciclovir pharmacokinetics in this population. METHODS: This prospective observational study included 24 lung transplant patients receiving valganciclovir prophylaxis. The cutoff value of trough ganciclovir concentration was estimated using receiver operating characteristic analysis in leukopenia grade 3 and higher. Population pharmacokinetic analysis was performed using a nonlinear mixed-effects modeling program. RESULTS: The trough ganciclovir concentration was significantly higher in the group with leukopenia grades 3 or higher than in the group with grades less than or equal to 2 (1605.7 ± 860.1 ng/mL [n = 3] vs. 380.5 ± 175.8 ng/mL (n = 21), p < .001). The cutoff value of trough ganciclovir concentration for predicting greater than or equal to grade 3 leukopenia was estimated as 872.0 ng/mL. Creatinine clearance and lung re-transplantation were found to have a significant impact on the total body clearance of valganciclovir. Ganciclovir clearance was decreased in patients with reduced creatine clearance or re-transplantation. CONCLUSION: These results suggest that higher ganciclovir trough concentrations are associated with an increased risk of leukopenia grade 3 or higher, and that creatinine clearance and lung re-transplantation affected the pharmacokinetics of ganciclovir.

Ex vivo delivery of regulatory T-cells for control of alloimmune priming in the donor lung.

BACKGROUND: Survival after lung transplantation (LTx) is hampered by uncontrolled inflammation and alloimmunity. Regulatory T-cells (Tregs) are being studied as a cellular therapy in solid organ transplantation. Whether these systemically administered Tregs can function at the appropriate location and time is an important concern. We hypothesised that in vitro-expanded recipient-derived Tregs can be delivered to donor lungs prior to LTx via ex vivo lung perfusion (EVLP), maintaining their immunomodulatory ability. METHODS: In a rat model, Wistar Kyoto (WKy) CD4+CD25high Tregs were expanded in vitro prior to EVLP. Expanded Tregs were administered to Fisher 344 (F344) donor lungs during EVLP; left lungs were transplanted into WKy recipients. Treg localisation and function post-transplant were assessed. In a proof-of-concept experiment, cryopreserved expanded human CD4+CD25+CD127low Tregs were thawed and injected into discarded human lungs during EVLP. RESULTS: Rat Tregs entered the lung parenchyma and retained suppressive function. Expanded Tregs had no adverse effect on donor lung physiology during EVLP; lung water as measured by wet-to-dry weight ratio was reduced by Treg therapy. The administered cells remained in the graft at 3 days post-transplant where they reduced activation of intra-graft effector CD4+ T-cells; these effects were diminished by day 7. Human Tregs entered the lung parenchyma during EVLP where they expressed key immunoregulatory molecules (CTLA4+, 4-1BB+, CD39+ and CD15s+). CONCLUSIONS: Pre-transplant Treg administration can inhibit alloimmunity within the lung allograft at early time points post-transplant. Our organ-directed approach has potential for clinical translation.

Clinical, radiological and pathological features of idiopathic and secondary interstitial pneumonia with pleuroparenchymal fibroelastosis in patients undergoing lung transplantation.

AIMS: Idiopathic pleuroparenchymal fibroelastosis (PPFE) is a rare type of idiopathic interstitial pneumonia, and pathological PPFE is also observed in patients with secondary interstitial pneumonia. This study aimed to evaluate the pathological findings associated with radiological PPFE-like lesions and the clinical and morphological features of patients with pathological PPFE. METHODS AND RESULTS: We retrospectively reviewed the pathology of the explanted lungs from 59 lung transplant recipients with radiological PPFE-like lesions. Pathological PPFE lesions were identified in 14 patients with idiopathic disease and in 12 patients with secondary disease. Pathological PPFE was associated with previous pneumothorax, volume loss in the upper lobes, and a flattened chest. Patients with idiopathic disease and those with secondary disease with pathological PPFE had similar clinical, radiological and pathological findings, whereas fibroblastic foci were more common in patients with idiopathic disease, and patients with secondary disease more frequently showed alveolar septal thickening with elastosis or fibrosis. Post-transplantation survival did not differ between patients with idiopathic and secondary disease with pathological PPFE (log-rank; P = 0.57) and was similar between patients with idiopathic disease with pathological PPFE and those with idiopathic pulmonary fibrosis (IPF) (log-rank; P = 0.62). CONCLUSIONS: Not all patients with interstitial pneumonia with radiological PPFE-like lesions have pathological PPFE. Characteristic clinical features can suggest the presence of pathological PPFE, and idiopathic and secondary cases with pathological PPFE are similar except for fibroblastic foci in idiopathic cases and alveolar septal thickening with elastosis or fibrosis in secondary cases. Patients with pathological PPFE have a similar prognosis to those with IPF after transplantation.

Improved absorption of itraconazole tablet by co-administration with lemon beverages in a lung transplant recipient: A case report.

After lung transplantation, itraconazole (ITCZ) is used as a prophylaxis for aspergillosis. ITCZ is a weak base with high lipophilicity, and the dissolution and absorption of ITCZ tablets and capsules are pH dependent. Therefore, ITCZ may not achieve sufficient serum concentrations in patients with higher gastric pH because of its poor bioavailability. We report a case of a woman in fifties with post-COVID-19 respiratory failure who successfully underwent lung transplantation, followed by improved bioavailability of ITCZ tablets when given with acidic lemon beverages. The patient was initially administered ITCZ oral solution; this was discontinued because of its unpleasant taste, nausea, and vomiting. The ITCZ oral solution was replaced with ITCZ tablets 78 days after transplantation; however, serum concentrations of ITCZ and hydroxy-ITCZ were below the detection limit (100 ng/mL). We co-administered ITCZ tablets with commercially available lemon beverages. Subsequently, serum concentrations of ITCZ and hydroxy-ITCZ increased to 341 and 673 ng/mL, respectively, on the 125th day after transplantation. Infection with fungi, including Aspergillus spp., was not observed in this case. The patient had no adverse events such as gastric ulcer or hyperglycemia. These results suggest that the co-administration of lemon beverages and ITCZ tablets may help achieve better absorption of ITCZ in patients taking acid suppressants.

High programmed death ligand 1 expression in carcinomatous components predicts a poor prognosis in pulmonary pleomorphic carcinoma.

PURPOSE: This study reviewed the clinicopathological characteristics and programmed death ligand 1 (PD-L1) expression of 46 patients with pulmonary pleomorphic carcinoma to better understand its clinical behavior and factors affecting the survival. METHODS: Data of patients with pulmonary pleomorphic carcinomas resected in our institution were retrospectively reviewed. The tumors were classified as carcinomatous or sarcomatous according to the tissue components. Pathological characteristics were evaluated on hematoxylin and eosin-stained sections. The percentages of tumor cells with membrane staining for PD-L1 in carcinomatous and sarcomatous components were determined. RESULTS: We reviewed data of 46 patients (41 males, 5 females; median age 70.5 years old, range 36-83 years old). Most patients with pulmonary pleomorphic carcinoma expressed PD-L1 (80.4%), and the proportion of PD-L1 expression in tumor cells was significantly higher in sarcomatous components than in carcinomatous components. In univariable analyses, high p-stage (III), necrosis on pathological findings, and high PD-L1 expression in carcinomatous components (≥ 50%) were poor prognostic factors for the overall survival. In multivariable analyses, high PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery. CONCLUSIONS: High PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery.

Patient-reported dyspnea and health predict waitlist mortality in patients waiting for lung transplantation in Japan.

BACKGROUND: Waitlist mortality due to donor shortage for lung transplantation is a serious problem worldwide. Currently, the selection of recipients in Japan is mainly based on the registration order. Hence, scientific evidence for risk stratification regarding waitlist mortality is urgently needed. We hypothesized that patient-reported dyspnea and health would predict mortality in patients waitlisted for lung transplantation. METHODS: We analyzed factors related to waitlist mortality using data of 203 patients who were registered as candidates for lung transplantation from deceased donors. Dyspnea was evaluated using the modified Medical Research Council (mMRC) dyspnea scale, and the health status was determined with St. George's Respiratory Questionnaire (SGRQ). RESULTS: Among 197 patients who met the inclusion criteria, the main underlying disease was interstitial lung disease (99 patients). During the median follow-up period of 572 days, 72 patients died and 96 received lung transplantation (69 from deceased donors). Univariable competing risk analyses revealed that both mMRC dyspnea and SGRQ Total score were significantly associated with waitlist mortality (p = 0.003 and p < 0.001, respectively) as well as age, interstitial lung disease, arterial partial pressure of carbon dioxide, and forced vital capacity. Multivariable competing risk analyses revealed that the mMRC and SGRQ score were associated with waitlist mortality in addition to age and interstitial lung disease. CONCLUSIONS: Both mMRC dyspnea and SGRQ score were significantly associated with waitlist mortality, in addition to other clinical variables such as patients' background, underlying disease, and pulmonary function. Patient-reported dyspnea and health may be measured through multi-dimensional analysis (including subjective perceptions) and for risk stratification regarding waitlist mortality.

Impacts of single nucleotide polymorphisms in Fc gamma receptor IIA (rs1801274) on lung transplant outcomes among Japanese lung transplant recipients.

This study aimed to analyze the influences of single nucleotide polymorphisms (SNPs) in Fc gamma receptor IIA (FCGR2A) on postoperative outcomes after lung transplantation (LTx). We enrolled 191 lung transplant recipients [80 undergoing living-donor lobar lung transplants (LDLLTs) and 111 undergoing deceased-donor lung transplants (DDLTs)] in this study. We identified SNPs in FCGR2A (131 histidine [H] or arginine [R]; rs1801274) and reviewed the infectious complication-free survival after ICU discharge. The SNPs in FCGR2A comprised H/H (n = 53), H/R (n = 24), and R/R (n = 3) in LDLLT and H/H (n = 67), H/R (n = 42), and R/R (n = 2) in DDLT. Recipients with H/H (H/H group) and those with H/R or R/R (R group) were compared in the analyses of infectious complications. In multivariate analyses, the R group of SNPs in FCGR2A was associated with pneumonia-free survival {HR: 2.52 [95% confidence interval (CI): 1.35-4.71], P = 0.004}, fungal infection-free survival [HR: 2.50 (95% CI: 1.07-5.84), P = 0.035], and cytomegalovirus infection-free survival [HR: 2.24 (95% CI: 1.07-4.69), P = 0.032] in LDLLT, but it was not associated with infectious complication-free survival in DDLT. Therefore, in LDLLT, more attention to infectious complications might need to be paid for LTx recipients with H/R or R/R than for those with H/H.

Sleep quality and its association with health-related quality of life of patients on lung transplantation waitlist in Japan.

PURPOSE: Poor quality of sleep is a common feature in patients with various lung diseases and affects their health-related quality of life (HRQL). We evaluated sleep quality and HRQL in patients on the waitlist for lung transplantation in Japan. METHODS: In this prospective study, patient-reported and physiological data were collected from patients newly registered on the waitlist for lung transplantation in Japan. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI) and HRQL using the St. George's Respiratory Questionnaire (SGRQ). The frequency of poor sleep quality, correlations between sleep quality and various clinical parameters, and predictive factors of sleep quality were examined. RESULTS: Of 193 patients, the three most-frequent indications for lung transplantation were interstitial pneumonia (n = 96), pulmonary complications of hematopoietic stem cell transplantation (n = 25), and pulmonary hypertension (n = 17). Poor sleep quality (PSQI > 5) was observed in 102 patients (53%) and was significantly associated with worse Hospital Anxiety and Depression Score (HADS), worse SGRQ score, worse modified Medical Research Council Dyspnea score, and shorter 6-min walk distance. However, it was not associated with sex, pulmonary function, interstitial pneumonia, or arterial blood gas. Stepwise multiple regression analysis indicated that poor sleep quality was explained significantly by HADS anxiety (23%) and SGRQ Symptoms (10%). CONCLUSION: Poor sleep quality was found to be common among patients on the lung transplantation waitlist in Japan. The two most significant factors responsible for impaired sleep quality were anxiety and respiratory symptoms. Additional care should be taken to ensuring a better quality of sleep for such patients.

A method for translational rat ex vivo lung perfusion experimentation.

The application of ex vivo lung perfusion (EVLP) has significantly increased the successful clinical use of marginal donor lungs. While large animal EVLP models exist to test new strategies to improve organ repair, there is currently no rat EVLP model capable of maintaining long-term lung viability. Here, we describe a new rat EVLP model that addresses this need, while enabling the study of lung injury due to cold ischemic time (CIT). The technique involves perfusing and ventilating male Lewis rat donor lungs for 4 h before transplanting the left lung into a recipient rat and then evaluating lung function 2 h after reperfusion. To test injury within this model, lungs were divided into groups and exposed to different CITs (i.e., 20 min, 6 h, 12 h, 18 h and 24 h). Experiments involving the 24-h-CIT group were prematurely terminated due to the development of severe edema. For the other groups, no differences in the ratio of arterial oxygen partial pressure to fractional inspired oxygen ([Formula: see text]/[Formula: see text]) were observed during EVLP; however, lung compliance decreased over time in the 18-h group (P = 0.012) and the [Formula: see text]/[Formula: see text] of the blood from the left pulmonary vein 2 h after transplantation was lower compared with 20-min-CIT group (P = 0.0062). This new model maintained stable lung function during 4-h EVLP and after transplantation when exposed to up to 12 h of CIT.

Diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration to assess tumor-programmed cell death ligand-1 expression in mediastinal lymph nodes metastasized from non-small cell lung cancer.

PURPOSE: We investigated the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) to evaluate programmed cell death ligand-1 (PD-L1) expression in patients with advanced non-small cell lung cancer (NSCLC). METHODS: A retrospective chart review of patients who underwent EBUS-TBNA between April 2017 and April 2019 was conducted. Among patients diagnosed with NSCLC, we investigated the rate of successful evaluation of tumor PD-L1 expression, compared the relevant factors between patients with evaluable and those with unevaluable PD-L1 expression, and examined the response to immune checkpoint inhibitors (ICIs) after EBUS-TBNA. RESULTS: Of the 40 patients assessed, 32 (80%) had evaluable PD-L1 expression. Patients with evaluable PD-L1 expression were older than those with unevaluable PD-L1 expression (p = 0.017), and we noted a tendency for a larger diameter of the biopsied lymph node (p = 0.12). The response rate to ICIs was 100% in patients with a tumor proportion score (TPS) ≥ 50%, 33% in those with a TPS 1-49%, and 0% in those with a TPS < 1%. CONCLUSION: The diagnostic yield of EBUS-TBNA to evaluate PD-L1 expression in advanced NSCLC appeared acceptable in association with relevant clinical outcomes after treatment with ICIs. A further prospective study with a larger sample size is required to confirm our findings.

Survival outcomes after minimally invasive thymectomy for early-stage thymic carcinoma.

Minimally invasive surgery (MIS) has occasionally been used for selected patients with thymoma, but there is little information on the MIS approach for thymic carcinoma. The aim of this study was to evaluate survival outcomes after MIS for early-stage (Masaoka stage I-II) thymic carcinoma and thymic neuroendocrine carcinoma. A retrospective chart review of the cases recorded in our multi-institutional database was performed to identify patients who underwent resection for thymic carcinoma between 1995 and 2017. MIS thymectomy was performed in 17 cases (VATS, n = 14; RATS, n = 3. male, 41%; median age, 72 years). The median follow-up period was 32.7 (range 7.4-106) months. The five-year overall survival and relapse-free survival rates were 84.4% and 77.8%, respectively. The present study demonstrated encouraging preliminary results regarding MIS for the treatment of early-stage thymic carcinoma and thymic neuroendocrine carcinoma. Further studies with a larger sample size are required to evaluate the indications for this surgery.

Immune function monitoring in lung transplantation using adenosine triphosphate production: time trends and relationship to postoperative infection.

PURPOSE: The ImmuKnow (IK) assay is a comprehensive immune function test that involves measuring adenosine triphosphate produced by the cluster of differentiation 4+ T lymphocytes in peripheral blood. The aim of this study was to analyze the time trends of IK values and assess the relationship between IK values and infections in lung transplants. METHODS: We prospectively collected 178 blood samples from 22 deceased-donor lung transplant (DDLT) recipients and 17 living-donor lobar lung transplant (LDLLT) recipients. A surveillance IK assay was performed postoperatively, then after 1 week and 1, 3, 6, and 12 months. RESULTS: Time trends of IK values in stable recipients peaked 1 week after DDLT (477 ± 247 ATP ng/ml), and 1 month after LDLLT (433 ± 134 ng/ml), followed by a gradual decline over 1 year. The mean IK values in infections were significantly lower than those in the stable state (119 vs 312 ATP ng/ml, p = 0.0002). CONCLUSIONS: IK values increased sharply after lung transplantation and then decreased gradually over time in the first year, suggesting a natural history of immune function. IK values were also significantly reduced during infections. These results may provide new insights into the utility of immune monitoring after lung transplantation.

Impact of the cardiac arrest mode on cardiac death donor lungs.

BACKGROUND: Donation after cardiac death (DCD) organs could alleviate the shortage of donor lungs. This study aimed to assess the influence on lung injuries of the way in which cardiac arrest was induced and to investigate the mechanisms leading to any differences. MATERIALS AND METHODS: Male rats were allocated into three groups as follows: sham (no warm ischemia), ventricular fibrillation (VF), and asphyxia group. Cardiac arrest was induced by either VF by way of a fibrillator or asphyxia caused by withdrawal of ventilation, which reflected uncontrolled and controlled DCD situations, respectively. The impact on lung flushing after 60 min of warm ischemia time was evaluated (n = 5, in each group). The physiological functions of the lungs in an isolated lung perfusion circuit were also evaluated with warm ischemia time prolonged to 150 min (n = 8, in each group). Messenger RNA expression levels of surfactant proteins (SPs) and inflammatory cytokines, pathologic findings, and high-energy phosphates of the lung tissues were investigated. RESULTS: In the asphyxia group, flushing and physiological functions in the isolated lung perfusion circuit were the most severely affected. Reverse transcription-polymerase chain reaction and pathologic findings revealed depletion of surfactant protein (SP)-C in lung tissues of the asphyxia group after reperfusion. The VF group was characteristic with elevated pulmonary vascular resistance. CONCLUSIONS: Lung injuries were mainly attributed to alveolar wall damage and depletion of SP in the asphyxia group, and perivascular area prominent edema in the VF group. DCD donor lungs were affected differently by the way in which cardiac arrest was induced.

Letermovir prophylaxis for cytomegalovirus in lung-transplant recipients: a comprehensive study with literature review of off-label use and real-world experiences.

Letermovir, initially approved for cytomegalovirus (CMV) prophylaxis in hematopoietic stem-cell transplantation, has gained attention for off-label use in lung-transplant (LTx) recipients. Given the high susceptibility of LTx recipients to CMV infection, this study explores the effectiveness and safety of letermovir prophylaxis. A retrospective analysis of using letermovir for LTx recipients at Tohoku University Hospital (January 2000 to November 2023) was conducted. Case summaries from other Japanese transplant centers and a literature review were included. Six cases at Tohoku University Hospital and one at Kyoto University Hospital were identified. Prophylactic letermovir use showed positive outcomes in managing myelosuppression and preventing CMV replication. The literature review supported the safety of letermovir in high-risk LTx recipients. Despite limited reports, our findings suggest letermovir's potential as prophylaxis for LTx recipients intolerant to valganciclovir. Safety, especially in managing myelosuppression, positions letermovir as a promising option. However, careful consideration is important in judiciously integrating letermovir into the treatment protocol.