Immune checkpoint molecules in solid organ transplantation: A promising way to prevent rejection.

Immune checkpoint (IC) molecules modulate immune responses upon antigen presentation; the interaction between different IC molecules will result in the stimulation or, rather, the thwarting of such responses. Tumor cells express increased amounts of inhibitory IC molecules in an attempt to evade immune responses; therapeutic agents have been developed that bind inhibitory IC molecules, restoring tumor-directed immune responses and changing the prognosis of a number of cancers. Stimulation of inhibitory IC molecules could be beneficial in preventing rejection in the setting of solid organ transplantation (SOT), and in vivo as well as in vivo results obtained in animal models show this to indeed to be the case. With the exception of belatacept, a monoclonal antibody (mAb) in which an IgG Fc fragment is linked to the extracellular domain of CTLA-4, this has not yet translated into the generation of novel therapeutic approaches to prevent SOT rejection. We provide a review of state-of-the art knowledge on the role played by IC molecules in transplantation, confident that innovative research will lead to new avenues to manage rejection in solid organ transplant.

Lung donor bronchoalveolar lavage positivity: Incidence, risk factors, and lung transplant recipients' outcome.

BACKGROUND: Inconsistent data exists regarding the risk factors for bronchoalveolar lavage (BAL) positivity in lung donors, the incidence of donor-derived infections (DDI), and the effect of BAL positivity on lung transplant (LuTx) recipients' outcome. METHODS: A retrospective analysis was conducted on consecutive LuTx at a single center from January 2016 to December 2022. Donors' data, including characteristics, graft function and BAL samples were collected pre-procurement. Recipients underwent BAL before LuTx and about the 3rd, 7th and 14th day after LuTx. A DDI was defined as BAL positivity (bacterial growth ≥104 colony forming units) for identical bacterial species between donor and recipient. Recipients' pre-operative characteristics, intra-operative management, and post-operative outcomes were assessed. Two recipient cohorts were identified based on lung colonization status before undergoing LuTx. RESULTS: Out of 188 LuTx procedures performed, 169 were analyzed. Thirty-six percent of donors' BAL tested positive. Donors' characteristics and graft function at procurement were not associated with BAL positivity. Fourteen DDI were detected accounting for 23% of recipients receiving a graft with a positive BAL. Only among uncolonized recipients, receiving a graft with positive BAL is associated with higher likelihood of requiring invasive ventilation at 72 hours after LuTx on higher positive end-expiratory pressure levels having lower PaO2/FiO2, prolonged duration of mechanical ventilation and longer ICU stay. No difference in hospital length of stay was observed. CONCLUSIONS: Receiving a graft with a positive BAL, which is poorly predicted by donors' characteristics, carries the risk of developing a DDI and is associated to a worse early graft function among uncolonized recipients.

Pathophysiological profile of non-ventilated lung injury in healthy female pigs undergoing mechanical ventilation.

BACKGROUND: Lung regions excluded from mechanical insufflation are traditionally assumed to be spared from ventilation-associated lung injury. However, preliminary data showed activation of potential mechanisms of injury within these non-ventilated regions (e.g., hypoperfusion, inflammation). METHODS: In the present study, we hypothesized that non-ventilated lung injury (NVLI) may develop within 24 h of unilateral mechanical ventilation in previously healthy pigs, and we performed extended pathophysiological measures to profile NVLI. We included two experimental groups undergoing exclusion of the left lung from the ventilation with two different tidal volumes (15 vs 7.5 ml/kg) and a control group on bilateral ventilation. Pathophysiological alteration including lung collapse, changes in lung perfusion, lung stress and inflammation were measured. Lung injury was quantified by histological score. RESULTS: Histological injury score of the non-ventilated lung is significantly higher than normally expanded lung from control animals. The histological score showed lower intermediate values (but still higher than controls) when the tidal volume distending the ventilated lung was reduced by 50%. Main pathophysiological alterations associated with NVLI were: extensive lung collapse; very low pulmonary perfusion; high inspiratory airways pressure; and higher concentrations of acute-phase inflammatory cytokines IL-6, IL-1ß and TNF-α and of Angiopoietin-2 (a marker of endothelial activation) in the broncho-alveolar lavage. Only the last two alterations were mitigated by reducing tidal volume, potentially explaining partial protection. CONCLUSIONS: Non-ventilated lung injury develops within 24 h of controlled mechanical ventilation due to multiple pathophysiological alterations, which are only partially prevented by low tidal volume.

Respiratory failure that occurs in cases of atelectasis, pneumonia and acute hypoxemic respiratory failure a machine called a mechanical ventilator is used to move air in and out of the patient's lungs. We know that the use of a mechanical ventilator can induce lung injury, but complete exclusion from ventilation might not be safe. Using pig lungs to mimic the patient's lungs, we evaluated the use of a ventilator against non-use. We find that the lungs sustained injury regardless of ventilator use. The non-ventilated lung injury consisted of collapse (lack of expansion), low amount of blood flow, high ventilation pressure and inflammatory response. Physicians should be aware that also the regions of the lung not receiving ventilation are at risk of injury.

Regional Ventilation-Perfusion Matching by Electrical Impedance Tomography After Single Lung Transplant.

Single lung transplantation (LUTX) can be the last therapeutic option for a growing cohort of patients suffering from end-stage respiratory failure. Postoperative ventilatory management of single LUTX recipients is challenged by the coexistence of the diseased native lung and a healthy-but fragile-graft. In this case report, in a single LUTX recipient with idiopathic pulmonary fibrosis, regional ventilation ( ), perfusion ( ), and / matching and subsequent measurement of shunt fraction ( Qs / Qt ) and alveolar dead space ( Vd / Vt ) were obtained by integrating electrical impedance tomography (EIT) with volumetric capnography and pulmonary thermodilution technique. Although the preoperative pulmonary scintigraphy showed predominant right lung perfusion (79.8% vs. 20.2%), the EIT documented the postoperative re-establishment of between the lungs (demonstrating the adequate functioning of vascular anastomoses), the diversion of to the graft and similar global Qs / Qt (17%) and Vd / Vt (29%) between native and graft lung. Electrical impedance tomography mapping allowed regional Qs / Qt and Vd / Vt assessment: the native right lung had a completely deranged distribution of and ( Qs / Qt 25%, Vd / Vt 46%), whereas the graft showed normal coupling of and ( Qs / Qt 8%, Vd / Vt 12%). Electrical impedance tomography may allow noninvasive, repeatable, bedside assessments of the lung / coupling after single LUTX.

Pneumonectomy for Unilateral Proximal Interruption of Pulmonary Artery: A Case Series from the Literature.

BACKGROUND: Unilateral proximal interruption of the pulmonary artery (UPIPA) is a rare congenital disease, and its optimal management remains undefined in the existing literature. The occasional necessity for pneumonectomy is still supported by limited evidence. METHODS: A systematic review of the literature was conducted using the PubMed search engine, focusing on UPIPA cases that received pneumonectomy. Thirty-one pertinent articles were selected and included in the analysis. A case reported from our institution was included in the analysis. RESULTS: We found 25 adults and seven children affected by UPIPA who received an indication for pneumonectomy, plus an additional case that was reported by our institution. Among adult patients, the predominant indication was hemoptysis (57%), followed by suspected or confirmed lung cancer (23%). Approximately 46% of surgical procedures were classified as urgent or emergent. Postoperative complications were observed in 36% of cases, with no recorded mortality. In pediatric cases, pneumonectomy was primarily a life-saving intervention, performed urgently or emergently in 75% of instances. A possible late complication in pediatric patients involves a mediastinal shift leading to respiratory distress, which may be mitigated using an inflatable prosthesis. CONCLUSIONS: Pneumonectomy achieves complete resolution of UPIPA symptoms. In the adult population, its primary indication is hemoptysis, with procedures conducted in both elective and urgent/emergent settings. Despite a mortality rate of zero, a notable proportion of patients may experience postoperative complications. In pediatric cases, the clinical presentation varies more extensively, and pneumonectomy is typically reserved for life-threatening situations, emphasizing the need for careful patient selection.

Pulmonary Lobectomy for Early-Stage Lung Cancer with Uniportal versus Three-Portal Video-Assisted Thoracic Surgery: Results from a Single-Centre Randomized Clinical Trial.

Video-assisted thoracic surgery (VATS) is a consolidated approach; however, there is no consensus on the number of ports leading to less postoperative pain. We compared early postoperative pain after uniportal and three-portal VATS lobectomy for early-stage NSCLC. In this randomized clinical trial, patients undergoing VATS lobectomy were randomly assigned to receive uniportal (U-VATS Group) or three-portal (T-VATS Group) VATS. The inclusion criteria were age ≤ 80 years and ASA < 4. The exclusion criteria were clinical T3, previous thoracic surgery, induction therapy, chest radiotherapy, connective tissue or vascular diseases, major organ failure, and analgesics or corticosteroids use. The postoperative analgesia protocol was based on NRS. Pain was measured as analgesic consumption; the secondary endpoints were intra- and postoperative complications, conversion rate, surgical time, dissected lymph nodes, hospital stay, and respiratory function. Out of 302 eligible patients, 120 were included; demographics were distributed homogeneously. The mean cumulative morphine consumption (CMC) in the U-VATS Group after 7 days was lower than in the T-VATS Group (77.4 mg vs. 90.1 mg, p = 0.003). Intraoperative variables and postoperative complications were comparable. The 30-day intercostal neuralgia rate was lower in the U-VATS Group, without reaching statistical significance. Patients undergoing U-VATS showed a lower analgesic consumption compared with the T-VATS Group; analgesic consumption was moderate in both groups.

Telemonitoring: An opportunity in cystic fibrosis lung transplant recipients.

Introduction: Telemedicine has been successfully employed in a wide range of conditions, such as such as chronic lung disease and COVID-19. This study evaluate the role of telemonitoring for the early diagnosis of acute lung allograft dysfunction in cystic fibrosis adults who underwent lung transplant (LuTx). Quality of life and functional level achieved during a 12 months follow up were assessed. Methods: Patients were randomized into two groups; control group received traditional hospital-based follow-up, whereas patients in the intervention group received, on top of standard care, a telemonitoring device, with a pulse oximeter and a spirometer integrated. Telemonitoring data were digitally transmitted to our centre. Results: Sixteen patients were enrolled in each group. No statistically significant difference was found between the two groups in terms of incidence of allograft dysfunction, time from onset of symptoms to diagnosis and time of occurrence from LuTx. Moreover, both groups achieved similar quality of life and functional level. With reference to the telemonitoring group: 1) hospital reported data were consistent with those being remotely registered; 2) adherence to telemonitoring decreased during the follow up; 3) the majority of patients reported a high degree of satisfaction. Conclusion: The COVID19 pandemic highlighted the necessity to investigate alternative practices to treat chronically ill individuals. Telemonitoring is a valuable tool to improve quality care to LuTx recipients.

Assessment of the 90-day mortality risk score after video-assisted thoracoscopic lobectomy in the Italian VATS Group cohort.

A five classes (A-E) aggregate risk score predicting 90-day mortality after video-assisted thoracoscopic lobectomy for lung cancer, including as independent factors male sex (3 points), DLCO <60% (1 point) and operative time >150 minutes (1 point), has been recently published. This study aims to assess the effectiveness and reliability of this risk model in a large, independent cohort of patients, to confirm its generalizability. From the Italian VATS Group Database, we selected 2,209 patients [60% males; median age 69 years (IQR:63-74)] who underwent video-assisted thoracoscopic lobectomy for non-small cell lung cancer. We calculated the aggregate risk score and the corresponding class of 90-day mortality risk for each patient. The correlation between risk classes and mortality rates was tested by Spearman's r-test. Model calibration was evaluated by Hosmer-Lemeshow goodness-of-fit test. Class A-E 90-day mortality rates were 0.33%, 0.51%, 1.39%, 1.31% and 2.56%, respectively. A strong uphill correlation was identified between risk classes and 90-day mortality (r=0.90; p=0.037), showing a positive correlation between increased mortality rate and class A to E. Hosmer-Lemeshow chi-squared value was 67.47 (p<0.001) with overall, Class D and E significantly lower 90-day mortality in our cohort than in the original one [1.04% vs 2.5% (p=0.018), 1.31% vs 5.65% (p=0.005) and 2.56% vs 18.75% (p=0.007), respectively]. Despite our data show a positive correlation between 90-day mortality and risk classes from A to E with modest discriminatory performance, the poor calibration suggests the need for model recalibration using local data to better manage and counsel lung cancer patients eligible for video-assisted thoracoscopic lobectomy.

Bone Disease in Long-Term Lung Transplant Survivors.

BACKGROUND: During the first two years after lung transplantation (LTx), the incidence of fragility fractures (FX) is estimated to be 15-50% and it is lower in patients with cystic fibrosis (CF) as compared with other end-stage lung diseases (nCF). The aim of our study is to compare the skeletal outcomes, after the first 2 years post-LTx, in long-term survivors with CF and nCF. MATERIALS AND METHODS: We evaluated the FX rate, the changes in bone mineral density (BMD) and trabecular bone score (TBS) in 68 patients (38 CF and 30 nCF) who underwent LTx in our center and with a follow-up after LTx longer than 5 years (7.3 ± 2.0 years). RESULTS: After the second year post-LTx: (i) the FX rate was lower than during the first two years post-LTx (4.4 vs. 20.6%, p = 0.004), with no difference between CF and nCF patients (5.3 vs. 3.3%, p = 0.589); (ii) BMD at lumbar spine, femoral neck and total hip remained stable (-1.6 ± 1.0 vs. -1.4 ± 1.1, p = 0.431, -1.8 ± 0.9 vs. -1.9 ± 0.9, p = 0.683, -1.5 ± 0.9 vs. -1.4 ± 0.9, p = 0.678, respectively) as well as TBS (1.200 ± 0.124 vs. 1.199 ± 0.205, p = 0.166). CONCLUSIONS: After the second year post-LTx, the skeletal complications become less frequent and have similar incidence in patients with CF and nCF.

Oncological Outcomes of Segmentectomy versus Lobectomy in Clinical Stage I Non-Small Cell Lung Cancer up to Two Centimeters: Systematic Review and Meta-Analysis.

OBJECTIVE: In recent years, pulmonary segmentectomy has emerged as an alternative to lobectomy for the treatment of patients with clinical stage I non-small cell lung cancer. Considering the conflicting results reported in the literature, the oncological effectiveness of segmentectomy remains controversial. To provide new insight into oncological results, we reviewed the literature, including recent randomized trials. METHODS: We performed a systematic review for surgical treatment of stage I NSCLC up to 2 cm using MEDLINE and the Cochrane Database from 1990 to December 2022. Primary outcomes for pooled analysis were overall and disease-free survival; secondary outcomes were postoperative complications and 30-day mortality. RESULTS: Eleven studies were considered for the meta-analysis. The pooled analysis included 3074 and 2278 patients who received lobectomy and segmentectomy, respectively. The estimated pooled hazard ratio showed a similar hazard for segmentectomy compared to lobectomy in terms of overall and disease-free survival. The restricted mean survival time difference between the two procedures was statistically and clinically not significant for overall and disease-free survival. Nevertheless, the overall survival hazard ratio was time-dependent: segmentectomy was at a disadvantage starting from 40 months after surgery. Six papers reported 30-day mortality: there were no events on 1766 procedures. The overall relative risk showed that the postoperative complication rate was higher in segmentectomy compared to lobectomy, without statistical significance. CONCLUSIONS: Our results suggest that segmentectomy might be a useful alternative to lobectomy for stage I NSCLC up to 2 cm. However, this appears to be time-dependent; in fact, the risk ratio for overall mortality becomes unfavorable for segmentectomy starting at 40 months after surgery. This last observation, together with some still undefined questions (solid/non-solid ratio, depth of the lesion, modest functional savings, etc.), leave room for further investigations on the real oncological effectiveness of segmentectomy.

Comparison Between Electronic and Traditional Chest Drainage Systems: A Multicenter Randomized Study.

BACKGROUND: Air leak is the major factor that influences the permanence of the chest tube and the in-hospital length of stay (LOS) among patients undergoing lung resections. The aim of this study was to determine whether the use of digital chest drain systems, compared with traditional ones, reduced the duration of chest drainage and postoperative in-hospital LOS in patients undergoing video-assisted thoracoscopic (VATS) lobectomy. METHODS: The study was a prospective, randomized, multicenter trial. Patients undergoing VATS lobectomy were randomized in 2 groups, receiving a digital drain system or a traditional one and managed accordingly to the protocol. RESULTS: Among 503 patients who fulfilled inclusion criteria and were randomized, 38 dropped out after randomization. Finally, 465 patients were analyzed, of whom 204 used the digital device and 261 the traditional one. In the digital group, there was a significantly shorter median chest tube duration of 3 postoperative days (interquartile range [IQR], 2-4 days) vs 4 postoperative days (IQR, 3-4 days; P = .001) and postoperative in-hospital LOS of 4 days (IQR, 3-6 days) vs 5 days (IQR, 4-6 days; P = .035). Analysis of predictors for increased duration of air leaks showed a relationship with male sex (P = .039), forced expiratory volume in 1 second percentage (P = .004), forced vital capacity percentage (P = .03), and presence of air leaks at the end of surgery (P = .001). CONCLUSIONS: In patients undergoing VATS lobectomy, the use of a digital drainage system allows an earlier removal of the chest drain compared with the traditional system, leading to a shorter in-hospital LOS.

Lung Transplantation From Controlled and Uncontrolled Donation After Circulatory Death (DCD) Donors With Long Ischemic Times Managed by Simple Normothermic Ventilation and Ex-Vivo Lung Perfusion Assessment.

Donation after cardiac death (DCD) donors are still subject of studies. In this prospective cohort trial, we compared outcomes after lung transplantation (LT) of subjects receiving lungs from DCD donors with those of subjects receiving lungs from donation after brain death (DBD) donors (ClinicalTrial.gov: NCT02061462). Lungs from DCD donors were preserved in-vivo through normothermic ventilation, as per our protocol. We enrolled candidates for bilateral LT ≥14 years. Candidates for multi-organ or re-LT, donors aged ≥65 years, DCD category I or IV donors were excluded. We recorded clinical data on donors and recipients. Primary endpoint was 30-day mortality. Secondary endpoints were: duration of mechanical ventilation (MV), intensive care unit (ICU) length of stay, severe primary graft dysfunction (PGD3) and chronic lung allograft dysfunction (CLAD). 121 patients (110 DBD Group, 11 DCD Group) were enrolled. 30-day mortality and CLAD prevalence were nil in the DCD Group. DCD Group patients required longer MV (DCD Group: 2 days, DBD Group: 1 day, p = 0.011). ICU length of stay and PGD3 rate were higher in DCD Group but did not significantly differ. LT with DCD grafts procured with our protocols appears safe, despite prolonged ischemia times.

Brixia system of screws: a titanium modular system with wide applicability for reinforced sternal closure in cardiac and thoracic surgery.

The use of cannulated screws and titanium plates to reinforce the sternal closure or to treat sternal dehiscence after median sternotomy has already been suggested in several articles. The system proposed here has some important advantages over those already described. Moreover, thanks to its characteristics, this system can also be used to treat pathologies affecting the entire rib cage. The system consists of a first threaded cannulated screw that is inserted in the bone or chondral cartilage and accommodates a cap screw that is tightened into the first screw and fixes a plate according to the following scheme: a threaded cannulated screw/plate/cap screw (Brixia system of screws). This system allows the plates to be fixed on the anterior face of the ribs and/or sternum without the need to enlarge dissection of the tissue, thereby lowering the danger of haemorrhage and injury to the thoracic organs. For this reason, it is particularly suitable for treating post-sternotomy sternal dehiscence, but it can be used to reinforce the primary sternal closure (after median or transversal sternotomy) in high-risk patients with sternal dehiscence. Owing to the modular nature of the system, singular components can also be utilized independently.

A multicentric evaluation of pediatric lung transplantation in Italy.

BACKGROUND: Pediatric lung transplantation is performed in highly experienced centers due to the peculiar population characteristics. The literature is limited and not representative of individual countries' differences. The purpose of this study was to analyze the Italian experience. METHODS: A multicentric retrospective analysis was performed on 110 pediatric patients (<18 years old) who underwent lung transplantation from 1992 to 2019 at 9 Italian centers. Heart-lung transplantations and lung retransplantations were excluded. RESULTS: The population was composed of 44 male and 66 female patients, with a median age of 15 years. The most frequent indication was cystic fibrosis (83%). One quarter of patients were transplanted in an emergency setting. Median donors' Oto score and age were 1 and 15 years, respectively, with 43% of adult donors. In 17% of patients a graft reduction was performed. Postoperatively, the median duration of mechanical ventilation, intensive care unit, and in-hospital stay were 48 hours, 11 and 35 days, respectively. Thirty-day mortality was 6%, and 1-, 5-, and 10-year survival was 72%, 52%, and 33%, respectively. Risk factors for mortality were Oto score and recipients' body mass index. CONCLUSIONS: The outcomes of pediatric lung transplantation in Italy are comparable with current literature. Particular attention should be paid to the Oto score and recipient body mass index. Conversely, adult donors and graft reductions can be safely used to expand the donor pool.

Isolation and characterization of two newly established thymoma PDXs from two relapses of the same patient: a new tool to investigate thymic malignancies.

BACKGROUND: Thymic malignancies are a heterogeneous group of rare cancers for which systemic chemotherapy is the standard treatment in the setting of advanced, recurrent or refractory diseases. Both environmental and genetic risk factors have not been fully clarified and few target-specific drugs have been developed for thymic epithelial tumors. A major challenge in studying thymic epithelial tumors is the lack of preclinical models for translational studies. MAIN BODY: Starting from bioptic material of two consecutive recurrences of the same patient, we generated two patient-derived xenografts. The patient-derived xenografts models were characterized for histology by immunohistochemistry and mutations using next-generation sequencing. When compared to the original tumors resected from the patient, the two patient-derived xenografts had preserved morphology after the stain with hematoxylin and eosin, although there was a moderate degree of de-differentiation. From a molecular point of view, the two patient-derived xenografts maintained 74.3 and 61.8% of the mutations present in the human tumor of origin. SHORT CONCLUSION: The newly generated patient-derived xenografts recapitulate both the molecular characteristics and the evolution of the thymoma it derives from well, allowing to address open questions for this rare cancer.

Lung Transplant for ARDS after COVID-19: Long-Term Outcomes and Considerations about Detrimental Issues.

During the first outbreak of COVID-19 in Italy, based on the only few cases reported from a Chinese centre at the time, we performed lung transplantation in two patients with irreversible acute respiratory distress syndrome (ARDS) after COVID-19 at our centre. After two years, we report the outcomes of these cases and some considerations. The first patient, an 18-year-old male, is in excellent conditions twenty-four months after surgery. The second patient was a 48-year-old man; his airways were colonized by carbapenemase-producing klebsiella pneumoniae at the time of lung transplantation, and he had previously suffered from delirium and hallucinations in the intensive care unit. His postoperative clinical course was complicated by dysexecutive behaviour and then septic shock; he died 62 days after surgery. The recently reported experience of different transplantation centres has led to the inclusion of irreversible acute respiratory distress syndrome (ARDS) after COVID-19 among the indications for lung transplantation in carefully selected patients. Our results confirm the feasibility and the good long-term outcomes of lung transplantation for COVID-19-associated ARDS. Nonetheless, our experience corroborates the need for careful recipient selection: special attention must be paid to the single-organ dysfunction principle, the evaluation of any neuro-psychiatric disorder, and MDR germs colonization, before listing.

Longitudinal assessment of renal function after lung transplantation for cystic fibrosis: transition from post-operative acute kidney injury to acute kidney disease and chronic kidney failure.

INTRODUCTION: The clinical trajectory of post-operative acute kidney injury (AKI) following lung transplantation for cystic fibrosis is unknown. METHODS: Incidence and risk factors for post-operative AKI, acute kidney disease (AKD) and chronic kidney disease (CKD) were retrospectively analyzed in cystic fibrosis patients undergoing lung transplantation. Logistic regressions, Chi-square, Cuzick rank tests, and Cox-proportional hazard models were used. RESULTS: Eighty-three patients were included. Creatinine peaked 3[2-4] days after transplantation, with 15(18%), 15(18%), and 20(24%) patients having post-operative AKI stages 1, 2, and 3, while 15(18%), 19(23%) and 10(12%) developed AKD stage 1, stage 2 and 3, respectively. Higher AKI stage was associated with worsening AKD (p = 0.009) and CKD (p = 0.015) stages. Of the 50 patients with AKI, 32(66%) transitioned to AKD stage > 0, and then 27 (56%) to CKD stage > 1. Female sex, extracorporeal membrane oxygenation support as a bridge to lung transplant and at the end of the surgery, the use of intraoperative blood components, and cold-ischemia time were associated with increased risk of post-operative AKI and AKD. Higher AKI stage prolonged invasive mechanical ventilation (p = 0.0001), ICU stay (p = 0.0001), and hospital stay (p = 0.0001), and increased the incidence of primary graft dysfunction (p = 0.035). Both AKI and AKD stages > 2 worsened long-term survival with risk ratios of 3.71 (1.34-10.2), p = 0.0131 and 2.65(1.02-6.87), p = 0.0443, respectively. DISCUSSION: AKI is frequent in cystic fibrosis patients undergoing lung transplantation, it often evolves to AKD and to chronic kidney disease, thereby worsening short- and long-term outcomes.

LKB1: Can We Target an Hidden Target? Focus on NSCLC.

LKB1 (liver kinase B1) is a master regulator of several processes such as metabolism, proliferation, cell polarity and immunity. About one third of non-small cell lung cancers (NSCLCs) present LKB1 alterations, which almost invariably lead to protein loss, resulting in the absence of a potential druggable target. In addition, LKB1-null tumors are very aggressive and resistant to chemotherapy, targeted therapies and immune checkpoint inhibitors (ICIs). In this review, we report and comment strategies that exploit peculiar co-vulnerabilities to effectively treat this subgroup of NSCLCs. LKB1 loss leads to an enhanced metabolic avidity, and treatments inducing metabolic stress were successful in inhibiting tumor growth in several preclinical models. Biguanides, by compromising mitochondria and reducing systemic glucose availability, and the glutaminase inhibitor telaglenastat (CB-839), inhibiting glutamate production and reducing carbon intermediates essential for TCA cycle progression, have provided the most interesting results and entered different clinical trials enrolling also LKB1-null NSCLC patients. Nutrient deprivation has been investigated as an alternative therapeutic intervention, giving rise to interesting results exploitable to design specific dietetic regimens able to counteract cancer progression. Other strategies aimed at targeting LKB1-null NSCLCs exploit its pivotal role in modulating cell proliferation and cell invasion. Several inhibitors of LKB1 downstream proteins, such as mTOR, MEK, ERK and SRK/FAK, resulted specifically active on LKB1-mutated preclinical models and, being molecules already in clinical experimentation, could be soon proposed as a specific therapy for these patients. In particular, the rational use in combination of these inhibitors represents a very promising strategy to prevent the activation of collateral pathways and possibly avoid the potential emergence of resistance to these drugs. LKB1-null phenotype has been correlated to ICIs resistance but several studies have already proposed the mechanisms involved and potential interventions. Interestingly, emerging data highlighted that LKB1 alterations represent positive determinants to the new KRAS specific inhibitors response in KRAS co-mutated NSCLCs. In conclusion, the absence of the target did not block the development of treatments able to hit LKB1-mutated NSCLCs acting on several fronts. This will give patients a concrete chance to finally benefit from an effective therapy.

Inhaled CO2 vs. Hypercapnia Obtained by Low Tidal Volume or Instrumental Dead Space in Unilateral Pulmonary Artery Ligation: Any Difference for Lung Protection?

Background: Unilateral ligation of the pulmonary artery (UPAL) induces bilateral lung injury in pigs undergoing controlled mechanical ventilation. Possible mechanisms include redistribution of ventilation toward the non-ligated lung and hypoperfusion of the ligated lung. The addition of 5% CO2 to the inspiratory gas (FiCO2) prevents the injury, but it is not clear whether lung protection is a direct effect of CO2 inhalation or it is mediated by plasmatic hypercapnia. This study aims to compare the effects and mechanisms of FiCO2 vs. hypercapnia induced by low tidal volume ventilation or instrumental dead space. Methods: Healthy pigs underwent left UPAL and were allocated for 48 h to the following: Volume-controlled ventilation (VCV) with VT 10 ml/kg (injury, n = 6); VCV plus 5% FiCO2 (FiCO2, n = 7); VCV with VT 6 ml/kg (low VT, n = 6); VCV plus additional circuit dead space (instrumental VD, n = 6). Histological score, regional compliance, wet-to-dry ratio, and inflammatory infiltrate were assessed to evaluate lung injury at the end of the study. To investigate the mechanisms of protection, we quantified the redistribution of ventilation to the non-ligated lung, as the ratio between the percentage of tidal volume to the right and to the left lung (VTRIGHT/LEFT), and the hypoperfusion of the ligated lung as the percentage of blood flow reaching the left lung (PerfusionLEFT). Results: In the left ligated lung, injury was prevented only in the FiCO2 group, as indicated by lower histological score, higher regional compliance, lower wet-to-dry ratio and lower density of inflammatory cells compared to other groups. For the right lung, the histological score was lower both in the FiCO2 and in the low VT groups, but the other measures of injury showed lower intensity only in the FiCO2 group. VTRIGHT/LEFT was lower and PerfusionLEFT was higher in the FiCO2 group compared to other groups. Conclusion: In a model of UPAL, inhaled CO2 but not hypercapnia grants bilateral lung protection. Mechanisms of protection include reduced overdistension of the non-ligated and increased perfusion of the ligated lung.