Single-cell and bulk RNA sequencing analysis of B cell marker genes in TNBC TME landscape and immunotherapy.

Objective: This study amied to investigate the prognostic characteristics of triple negative breast cancer (TNBC) patients by analyzing B cell marker genes based on single-cell and bulk RNA sequencing. Methods: Utilizing single-cell sequencing data from TNBC patients, we examined tumor-associated B cell marker genes. Transcriptomic data from The Cancer Genome Atlas (TCGA) database were used as the foundation for predictive modeling. Independent validation set was conducted using the GSE58812 dataset. Immune cell infiltration into the tumor was assessed through various, including XCELL, TIMER, QUANTISEQ, CIBERSORT, CIBERSORT-ABS, and ssGSEA. The TIDE score was utilized to predict immunotherapy outcomes. Additional investigations were conducted on the immune checkpoint blockade gene, tumor mutational load, and the GSEA enrichment analysis. Results: Our analysis encompassed 22,106 cells and 20,556 genes in cancerous tissue samples from four TNBC patients, resulting in the identification of 116 B cell marker genes. A B cell marker gene score (BCMG score) involving nine B cell marker genes (ZBP1, SEL1L3, CCND2, TNFRSF13C, HSPA6, PLPP5, CXCR4, GZMB, and CCDC50) was developed using TCGA transcriptomic data, revealing statistically significant differences in survival analysis (P<0.05). Functional analysis demonstrated that marker genes were predominantly associated with immune-related pathways. Notably, substantial differences between the higher and lower- BCMG score groups were observed in terms of immune cell infiltration, immune cell activity, tumor mutational burden, TIDE score, and the expression of immune checkpoint blockade genes. Conclusion: This study has established a robust model based on B-cell marker genes in TNBC, which holds significant potential for predicting prognosis and response to immunotherapy in TNBC patients.

NETosis promotes chronic inflammation and fibrosis in systemic lupus erythematosus and COVID-19.

Pulmonary fibrosis, a serious complication of systemic lupus erythematosus (SLE) and coronavirus disease 2019 (COVID-19), leads to irreversible lung damage. However, the underlying mechanism of this condition remains unclear. In this study, we revealed the landscape of transcriptional changes in lung biopsies from individuals with SLE, COVID-19-induced pulmonary fibrosis, and idiopathic pulmonary fibrosis (IPF) using histopathology and RNA sequencing, respectively. Despite the diverse etiologies of these diseases, lung expression of matrix metalloproteinase genes in these diseases showed similar patterns. Particularly, the differentially expressed genes were significantly enriched in the pathway of neutrophil extracellular trap formation, showing similar enrichment signature between SLE and COVID-19. The abundance of Neutrophil extracellular traps (NETs) was much higher in the lungs of individuals with SLE and COVID-19 compared to those with IPF. In-depth transcriptome analyses revealed that NETs formation pathway promotes epithelial-mesenchymal transition (EMT). Furthermore, stimulation with NETs significantly up-regulated α-SMA, Twist, Snail protein expression, while decreasing the expression of E-cadherin protein in vitro. This indicates that NETosis promotes EMT in lung epithelial cells. Given drugs that are efficacious in degrading damaged NETs or inhibiting NETs production, we identified a few drug targets that were aberrantly expressed in both SLE and COVID-19. Among these targets, the JAK2 inhibitor Tofacitinib could effectively disrupted the process of NETs and reversed NET-induced EMT in lung epithelial cells. These findings support that the NETs/EMT axis, activated by SLE and COVID-19, contributes to the progression of pulmonary fibrosis. Our study also highlights that JAK2 as a potential target for the treatment of fibrosis in these diseases.

Ligustilide, a novel SIRT1 agonist, alleviates lipopolysaccharide-induced acute lung injury through deacetylation of NICD.

Development and progression of sepsis-induced acute lung injury (ALI) involve apoptosis and oxidative stress in lung epithelial cells. Ligustilide (LIG) is one of the main bioactive constituents derived from the Angelica sinensis. As a novel SIRT1 agonist, LIG owns powerful anti-inflammatory and antioxidative properties, exerting remarkable therapeutic effects on cancers, neurological disorders, and diabetes mellitus. However, whether LIG could protect against lipopolysaccharide (LPS)-induced ALI by activating SIRT1 remains unclear. Mice underwent intratracheal LPS injection to mimic sepsis-induced ALI while MLE-12 cells were treated with LPS for 6 h to establish an in vitro ALI model. At the same time, mice or MLE-12 cells were treated with different doses of LIG to access its pharmacological effect. The results demonstrated that LIG pretreatment could improve LPS-induced pulmonary dysfunction and pathological injury, apart from increasing 7-day survival rate. In addition, LIG pretreatment also decreased inflammation, oxidative stress and apoptosis during LPS-induced ALI. Mechanically, LPS stimulation decreased the expression and activity of SIRT1 but increased the expression of Notch1 and NICD. And LIG could also enhance the interaction between SIRT1 and NICD, thus deacetylating NICD. In vitro experiments also unveiled that EX-527, a selective SIRT1 inhibitor, could abolish LIG-elicited protection in LPS-treated MLE-12 cells. And in SIRT1 knockout mice with ALI, LIG pretreatment also lost its effects on inflammation, apoptosis, and oxidative stress during ALI.

AURKA, TOP2A and MELK are the key genes identified by WGCNA for the pathogenesis of lung adenocarcinoma.

The comprehensive analysis of single or multiple microarray datasets is currently available in Gene Expression Omnibus (GEO) databases, with several studies having identified genes strongly associated with the development of lung adenocarcinoma (LUAD). However, the mechanisms of LUAD development remain largely unknown and has not yet been systematically studied; thus, further studies are required in this field. In the present study, weighted gene co-expression network analysis (WGCNA) was used for the evaluation of key genes with potential high risk of LUAD, and to provide more reliable evidence concerning its pathogenesis. The GSE140797 dataset from the high-throughput GEO database was downloaded and was first analyzed using the Limma package in the R language in order to determine the differentially expressed genes. The dataset was then analyzed using the WGCNA package to analyze the co-expressed genes, and the modular genes with the highest correlation with the clinical phenotype were identified. Subsequently, the pathogenic genes shared in common between the result of the two analyses were imported into the STRING database for protein-protein interaction network analysis. The hub genes were screened out using Cytoscape, and then The Cancer Genome Atlas analysis, receiver operating characteristic analysis and survival analysis were subsequently performed. Finally, the key genes were evaluated using reverse transcription-quantitative PCR and western blot analysis. Bioinformatics analysis of the GSE140797 dataset revealed eight key genes: AURKA, BUB1, CCNB1, CDK1, MELK, NUSAP1, TOP2A and PBK. Finally, the AURKA, TOP2A and MELK genes were evaluated in samples from patients with lung cancer using WGCNA and RT-qPCR, western blot analysis experiments, providing basis for further research on the mechanisms of LUAD development and targeted therapy.

G-/C-rich ssDNA-based Fe and Cu/Fe nanoclusters with peroxidase-like activity for intracellular ROS production and cytotoxicity applications.

Five G-/C-rich single-stranded DNA (ssDNA) with different sequences and lengths were templated to prepare the DNA-Cu, DNA-Fe, and bimetallic DNA-Cu/M nanoclusters (NCs). The peroxidase-like activities of these nanomaterials were studied using H2O2 and 3,3',5,5''-tetramethylbenzidine (TMB) as the reaction substrates in HAc-NaAc buffer. It was found that T30-G2-Fe NCs and T30-G2-Cu/Fe NCs, with a size of about 2 nm, exhibit similar and the strongest enzyme-like activity under optimal conditions. Both NCs possess a similarly high affinity to substrates, and the Michaelis-Menten constant (Km) values to TMB and H2O2 are about 11 and 2-3 times lower than those of natural horseradish peroxidase (HRP), respectively. The activity of both nanozymes decreases to about 70% after being kept for one week in pH 4.0 buffer at 4 °C, which is comparable with HRP. Hydroxyl radicals (•OH) are the main reactive oxygen species (ROS) produced in the catalytic reaction. Moreover, both NCs can facilitate in situ generation of ROS in HeLa cells using endogenous H2O2. MTT assays indicate that the T30-G2-Cu/Fe NCs exhibit the strong selective cytotoxicity to HeLa cells over HL-7702 cells. The cellular viability is about 70% and 50% after incubating with 0.6 M NCs for 24 h without or with 2 mM H2O2, respectively. The current study shows that the T30-G2-Cu/Fe NCs have the potential for chemical dynamic treatment (CDT).

Comprehensive plasma metabolomics and lipidomics of benign and malignant solitary pulmonary nodules.

INTRODUCTION: Solitary pulmonary nodules (SPNs) are commonly found in imaging technologies, but are plagued by high false-positive rates. OBJECTIVE: We aimed to identify metabolic alterations in SPN etiology and diagnosis using less invasive plasma metabolomics and lipidomics. METHODS: In total, 1160 plasma samples were obtained from healthy volunteers (n = 280), benign SPNs (n = 157) and malignant SPNs (stage I, n = 723) patients enrolled from 5 independent centers. Gas chromatography-triple quadrupole mass spectrometry (GC‒MS) and liquid chromatography-Q Exactive Hybrid Quadrupole-Orbitrap mass spectrometry (LC‒MS) were used to analyze the samples for untargeted metabolomics and lipidomics. RESULTS AND CONCLUSION: GC‒MS-based metabolomics revealed 1336 metabolic features, while LC‒MS-based lipidomics revealed 6088 and 2542 lipid features in the positive and negative ion modes, respectively. The metabolic and lipidic characteristics of healthy vs. benign or malignant SPNs exhibited substantial pattern differences. Of note, benign and malignant SPNs had no significant variations in circulating metabolic and lipidic markers and were validated in four other centers. This study demonstrates evidence of early metabolic alterations that can possibly distinguish SPNs from healthy controls, but not between benign and malignant SPNs.

Contrasting impacts of forests on cloud cover based on satellite observations.

Forests play a pivotal role in regulating climate and sustaining the hydrological cycle. The biophysical impacts of forests on clouds, however, remain unclear. Here, we use satellite data to show that forests in different regions have opposite effects on summer cloud cover. We find enhanced clouds over most temperate and boreal forests but inhibited clouds over Amazon, Central Africa, and Southeast US. The spatial variation in the sign of cloud effects is driven by sensible heating, where cloud enhancement is more likely to occur over forests with larger sensible heat, and cloud inhibition over forests with smaller sensible heat. Ongoing forest cover loss has led to cloud increase over forest loss hotspots in the Amazon (+0.78%), Indonesia (+1.19%), and Southeast US (+ 0.09%), but cloud reduction in East Siberia (-0.20%) from 2002-2018. Our data-driven assessment improves mechanistic understanding of forest-cloud interactions, which remain uncertain in Earth system models.

First lung transplant in Wuhan for a critical and elderly COVID-19 patient.

INTRODUCTION: We report the case of a 65-year-old Coronavirus disease 2019 (COVID-19) patient with pneumonia and subsequent end-stage pulmonary failure who required 63 days of mechanical ventilation (MV) and 62 days of extracorporeal membrane oxygenation (ECMO). METHODS: On Day 45, a comprehensive interdisciplinary discussion on the best course of treatment resulted in the general consensus that his lungs would not recover. As such, he was evaluated and listed for a lung transplant. RESULTS: We performed a bilateral lung transplant, and the patient was weaned off ECMO and MV postoperatively. This is the first report of lung transplants in patients with COVID-19 in Wuhan. CONCLUSIONS: We suggest that a lung transplantation may be a viable treatment for patients with end-stage pulmonary failure secondary to COVID-19 in selected situations.

GC-MS Based Metabolomics Reveals the Synergistic Mechanism of Gardeniae Fructus-Forsythiae Fructus Herb Pair in Lipopolysaccharide-Induced Acute Lung Injury Mouse Model.

Compatibility remains among the crucial and significant characteristics of traditional Chinese medicines. The Gardeniae Fructus (FG)-Forsythiae Fructus (FF) herb pair, an epitome of formulations for heat-clearing and detoxification, is extensively used to treat bacterial pneumonia in clinical settings. However, there are few reports on their synergistic effects. This study thus investigated their compatibility by GC-MS based metabolomics using a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. Differential metabolites were identified by both variable importance in the projection (VIP) > 1 in orthogonal partial least-squares discriminant analysis (OPLS-DA) mode and P < 0.05. Results of biochemistry and histopathology indicated that FG-FF herb pair exerted more promising lung protective effect than its individual decoction against the LPS-induced ALI model. From the metabolomics study, 32 differential metabolites in vehicle vs. model groups, 21 differential metabolites in FF vs. model groups, 21 differential metabolites in FG vs. model groups, and 20 differential metabolites in FG-FF herb pair vs. model groups were found. Among them, the levels of 3-hydroxybutyric acid, alanine, isophthalic acid, and terephthalic acid were restored significantly in the FF group, while silanol and cholesterol were restored significantly in the FG group. For FG-FF treatment, the amount of behenic acid, a metabolite with anti-inflammatory properties, was increased, while palmitic acid, a proinflammatory metabolite, was decreased. Meanwhile, the two biomarkers were restored more significantly than that by FG or FF treatment, which indicated that the synergistic effects by FF coupled with FG might be attributed to restoring fatty acids metabolic pathway.

Plasma extracellular vesicle delivery of miR-210-3p by targeting ATG7 to promote sepsis-induced acute lung injury by regulating autophagy and activating inflammation.

Extracellular vesicles (EVs) can be used for intercellular communication by facilitating the transfer of miRNAs from one cell to a recipient cell. MicroRNA (miR)-210-3p is released into the blood during sepsis, inducing cytokine production and promoting leukocyte migration. Thus, the current study aimed to elucidate the role of plasma EVs in delivering miR-210-3p in sepsis-induced acute lung injury (ALI). Plasma EVs were isolated from septic patients, after which the expression of various inflammatory factors was measured using enzyme-linked immunosorbent assay. Cell viability and apoptosis were measured via cell counting kit-8 and flow cytometry. Transendothelial resistance and fluorescein isothiocyanate fluorescence were used to measure endothelial cell permeability. Matrigel was used to examine the tubulogenesis of endothelial cells. The targeting relationship between miR-210-3p and ATG7 was assessed by dual-luciferase reporter assays. The expression of ATG7 and autophagy-related genes was determined to examine autophagic activation. A sepsis mouse model was established by cecal ligation and puncture (CLP)-induced surgery. The level of miR-210-3p was highly enriched in septic EVs. MiR-210-3p enhanced THP-1 macrophage inflammation, BEAS-2B cell apoptosis, and HLMVEC permeability while inhibiting angiogenesis and cellular activity. MiR-210-3p overexpression reduced ATG7 and LC3II/LC3I expression and increased P62 expression. Improvements in vascular density and autophagosome formation, increased ATG7 expression, and changes in the ratio of LC3II/LC3I were detected, as well as reduced P62 expression, in adenovirus-anti-miR-210-3p treated mice after CLP injury. Taken together, the key findings of the current study demonstrate that plasma EVs carrying miR-210-3p target ATG7 to regulate autophagy and inflammatory activation in a sepsis-induced ALI model.

Effects of prolonged cold-ischemia on autophagy in the graft lung in a rat orthotopic lung transplantation model.

INTRODUCTION: Ischemia-reperfusion (I/R) injury causes present challenges in the field of graft transplantation which is also a major contributor to early graft dysfunction or failure after organ transplantation. The study focuses on the effects of prolonged cold-ischemia (CI) on the autophagic activity in the graft lung in a rat orthotopic lung transplantation model. MATERIAL AND METHODS: Donor lungs were preserved under CI conditions for different periods. An orthotopic lung transplantation model was developed, and the lung tissues from donor lungs subjected to CI preservation and reperfusion were harvested. We evaluated the effects of different CI periods on autophagy, reactive oxygen species (ROS) and glucose consumption. Additionally, the mechanism by which prolonged CI affected autophagy was investigated through determination of the molecules related to the mTOR pathway after treatment with 3-Methyladenine (3-MA), rapamycin and an adenosine triphosphate (ATP) synthase inhibitor oligomycin (OM). RESULTS: Prolonged CI led to increased activities of key glycolytic enzymes, glucose consumption and lactic acid production. Autophagy, ROS and glucose consumption were induced in the graft lung after I/R, which reached peak levels after 6 h and was gradually decreased. Most importantly, the perfusion treatment of 3-MA or OM decreased ROS level and autophagy, but increased the extent of mTOR phosphorylation, while the perfusion treatment of rapamycin induced ROS and autophagy. CONCLUSION: Taken together, autophagy mediated by a prolonged CI preservation affects the glucose consumption and ROS production in the graft lung via the mTOR signaling pathway.

The impacts of ubiquilin 1 (UBQLN1) knockdown on cells viability, proliferation, and apoptosis are mediated by p53 in A549 lung cancer cells.

BACKGROUND: Little is known about the relationship between ubiquilin 1 (UBQLN1) and p53, both of them have been implicated in the development and progression of non-small cell lung cancer (NSCLC). In this study, we aimed to explore the role of loss of UBQLN1 in cell viability and proliferation, and cell apoptosis in human lung adenocarcinoma A549 cells. METHODS: Cell viability, proliferation, and apoptosis were determined by MTT, BrdU, and TUNEL assays, respectively. Adenoviruses carrying cDNA or siRNA were used to overexpress or silence target protein. Dihydroethidium (DHE) staining was performed to measure the real-time formation of intracellular reactive oxygen species (ROS). The chymotrypsin-like activity of 20S proteasome core was determined by using synthetic fluorogenic peptide substrate. RESULTS: UBQLN1 silencing led to a reduction of p53 protein levels and overexpression of p53 reversed the effects of UBQLN1 knockdown (KD) on cell viability, proliferation, and apoptosis. Furthermore, deficiency of UBQLN1 activated autophagy activity but did not affect proteasome activity. Inhibition of autophagy restored p53 protein levels in UBQLN1-KD A549 cells. In addition, UBQLN1 KD markedly inhibited phosphorylation of mammalian target of rapamycin (mTOR) and its downstream ribosomal S6 kinase (S6K). CONCLUSIONS: Our experiments suggested that the regulation of UBQLN1 on cell viability, proliferation, and apoptosis was mediated by mTOR/autophagy/p53 signaling pathway.

Aß40 Promotes the Osteoblastic Differentiation of Aortic Valve Interstitial Cells through the RAGE Pathway.

Amyloid beta (Aß) peptide 40 enhances the activation of receptor for advanced glycation end products (RAGE) in immune-inflammatory diseases. RAGE exhibits several effects in the setting of numerous cardiovascular events. We hypothesized that the Aß40/RAGE pathway is involved in the osteoblastic differentiation of the valvular interstitial cell (VIC) phenotype, and RAGE knockout intervention could reduce the calcification of aortic valve interstitial cells (AVICs) by inhibiting the extracellular-regulated kinase1/2 (ERK1/2)/nuclear factor kappa-B (NF-κB) signaling pathway. To test this hypothesis, the activation of Aß40/RAGE pathway in human calcific AVs was evaluated with immunohistochemical staining. Cultured calcific VIC models were used in vitro. The VICs were stimulated using Aß40, with or without RAGE small interfering ribonucleic acid (siRNA), and ERK1/2 and NF-κB inhibitors for analysis. Our data revealed that Aß40 induced the ERK1/2/NF-κB signaling pathway and osteoblastic differentiation of AVICs via the RAGE pathway in vitro.

Double lung transplantation for end-stage Kartagener syndrome: a case report and literature review.

Kartagener syndrome (KS) is an autosomal recessive disorder characterized by situs inversus, paranasal sinusitis and bronchiectasis. We report the successful use of double lung transplant (DLTx) to treat end-stage KS. A 49-year-old Han woman was admitted to Renmin Hospital (Wuhan University, China) in September 2017 with a ≥15 year history of chronic productive cough that had worsened during the past year. Clinical examination and imaging investigations revealed respiratory failure and situs inversus consistent with KS. The patient was successfully treated with DLTx involving bilateral bronchial anastomoses. DLTx is a feasible treatment option for end-stage KS.

Surgery to the primary tumor is associated with improved survival of patients with metastatic esophageal cancer: propensity score-matched analyses of a large retrospective cohort.

The survival advantage of surgery to the primary tumor for patients with distant metastatic esophageal cancer has not been adequately evaluated. This study aims to investigate the role of surgery to the primary tumor in distant metastatic esophageal cancer and to evaluate possible different effects of surgery on survival of esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC). This study included a cohort of 4,367 metastatic esophageal cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database, registered from January 2004 to December 2014. Kaplan-Meier and Cox proportional hazardous models were used to evaluate the overall survival (OS) and corresponding 95% confidence interval (CI). Propensity score matching (PSM) was used to adjust for potential baseline confounding. Both EAC (median OS for surgery group vs. no-surgery group-14.0 vs. 9.0 months, P < 0.001) and ESCC (median OS for surgery vs. no-surgery group-11.0 vs. 7.0 months, P = 0.002) experienced survival benefits from surgery. We found that surgery to the primary tumor, when combined with chemotherapy, was associated with improved survival for patients with M1b disease, both EAC and ESCC, with a greater benefit observed in younger patients, and those with EAC. While the present data indicate a potential survival benefit from surgery for some patients with metastatic esophageal cancer, it is possible that performance status and metastatic disease burden impacted patient selection, influencing these results. Further studies are needed to determine the role of surgery for patients with metastatic esophageal cancer.

Effects of Warm Versus Cold Ischemic Donor Lung Preservation on the Underlying Mechanisms of Injuries During Ischemia and Reperfusion.

BACKGROUND: Ischemia-reperfusion injury related to lung transplantation is a major contributor to early postoperative morbidity and mortality. We hypothesized that donation after cardiac death donor lungs experience warm ischemic conditions that activate different injurious mechanisms compared with donor lungs that undergo prolonged cold ischemic conditions. METHODS: Rat donor lungs were preserved under different cold ischemic times (CIT) (12 hours or 18 hours), or under warm ischemia time (WIT) (3 hours) after cardiac death, followed by single left lung transplantation. Lung function was analyzed during the 2-hour reperfusion period. Microscopic injury, cell death, energy status, and inflammatory responses were assessed. RESULTS: Pulmonary oxygenation function was significantly worse in both 18hCIT and WIT groups, accompanied by higher peak airway pressure, acute lung injury scores, and expression of cell death markers compared with the 12hCIT control group. In lung tissue, reperfusion induced increased expression levels of interleukin (IL)-1α, IL-1ß, IL-6, and chemokines CCL2, CCL3, CXCL1, and CXCL2 in CIT lungs. Notably, these changes were much lower in the WIT group. Additionally, plasma levels of IL-6, IL-18, CCL2, and vascular endothelial growth factor were significantly higher, and adenosine triphosphate levels were significantly reduced in warm versus cold ischemic lungs. CONCLUSIONS: Compared with 12hCIT, posttransplant pathophysiology deteriorated similarly in both 18hCIT and WIT groups. However, tissue adenosine triphosphate levels and inflammatory profiling differed between warm versus cold ischemic donor lungs. These differences should be carefully considered when developing specific therapeutic strategies to reduce ischemia-reperfusion injury in lung transplantation.

α1-Anti-trypsin improves function of porcine donor lungs during ex-vivo lung perfusion.

BACKGROUND: Ex-vivo lung perfusion (EVLP), a technique for donor lung assessment, also represents a platform for donor lung repair and immunomodulation. α1-Anti-trypsin (A1AT), a medication used to treat emphysema in A1AT-deficient patients, has anti-inflammatory properties and has been shown to attenuate ischemia-reperfusion injury in rat and pig lung transplants. The objective of this study was to determine whether administration of A1AT during EVLP can improve donor lung quality after prolonged hypothermic preservation. METHODS: Pig donor lungs were retrieved, preserved at 4°C for 24 hours, and then subjected to normothermic EVLP for 12 hours using the Toronto protocol. The treatment group (n = 6) received 3 mg/ml A1AT (Zemaira) in the EVLP perfusate, acellular Steen solution. The control group (n = 6) was perfused with Steen solution only. Physiologic functions and gas exchange were measured hourly. Pulmonary edema, lung injury, apoptosis and inflammatory mediators were evaluated in lung tissues and perfusate. RESULTS: A1AT treatment significantly reduced pulmonary arterial pressure, pulmonary vascular resistance and airway pressure changes from the baseline when compared with controls. A1AT treatment significantly improved both dynamic and static pulmonary compliance, and change in partial pressure of oxygen (ΔPO2) between the left atrium and the pulmonary artery. Furthermore, A1AT treatment also significantly reduced pulmonary edema (wet-to-dry ratio), pulmonary cell apoptosis and pro-inflammatory cytokine levels (interleukin-1α and -8) in the perfusate. CONCLUSION: Treatment of 24-hour-preserved pig donor lungs with A1AT during EVLP resulted in improved physiologic function, reduced pulmonary edema and inflammation and decreased cell death. Our findings suggest that treatment of donor lungs during EVLP with A1AT is a promising strategy to attenuate early lung injury and improve donor lung function before lung transplantation.

Human α1-antitrypsin improves early post-transplant lung function: Pre-clinical studies in a pig lung transplant model.

BACKGROUND: The translation of novel drugs in lung transplantation is challenged by different physiologic conditions between small animals and humans. Large-animal models provide important pre-clinical evidence and the next step that best informs clinical trials. In the present study, we used a pig lung transplant model to determine whether human α1-antitrypsin (A1AT), a medication shown to prevent pulmonary ischemia-reperfusion injury in rats, could attenuate reperfusion injury after prolonged hypothermic preservation in a large-animal lung transplant model. METHODS: Donor lungs were preserved for 24 hours at 4°C, followed by lung transplantation. In a randomized and blinded fashion, intravenous A1AT (240 mg/kg; n = 5) or human albumin (n = 5) was administered to the recipient before reperfusion. Allograft gas exchange function and lung mechanics were monitored during a 4-hour reperfusion period. Microscopic lung injury, inflammatory response, coagulation activity, and cell death were assessed. RESULTS: Pulmonary gas exchange was significantly better during the 4-hour reperfusion period in the A1AT group. Treatment with A1AT improved static pulmonary compliance and significantly reduced pulmonary edema and lung permeability. A1AT treatment inhibited inflammatory mediators in the circulation, with reduced activation of nuclear factor-κB and inflammasome, reduced formation of thrombin-antithrombin complex in plasma, and reduced apoptosis in the allografts. CONCLUSIONS: Administration of human A1AT before reperfusion in recipients improved immediate post-transplant lung function in pigs. A large-animal survival model should be considered to support further advancement toward a clinical trial of A1AT to prevent primary graft dysfunction in lung transplantation.