Lung Damage Research Articles

291. CLINICAL OUTCOMES OF IMMUNOCHEMOTHERAPY FOR UNRESECTABLE OR RECURRENT ESOPHAGEAL SQUAMOUS CELL CARCIONOMA

Abstract Background/Aim KEYNOTE-590 and CheckMate 648 study showed significantly feasible clinical outcomes in patients with advanced esophageal carcinoma. Herein, we report our clinical results of immunochemotherapy for unresectable and recurrent esophageal squamous cell carcinoma. Patients and Methods 17 patients who received pembrolizumab plus 5-fluorouracil and cisplatin (IO+C) and 9 patients who received nivolumab plus ipilimumab (IO+IO) were enrolled. Results The median age of the IO+C group was 70 years, and all patients had unresectable disease. A median of 2 courses of treatment were performed, and the best overall response rate was 68.6% including CR in 2 patients, PR in 9 patients, SD in 4 patients, PD in 1 patient and NE in 1 patient. One-year progression-free survival rate (PFS) was 36.1% and one-year overall survival (OS) was 64.6%. Immune-related adverse events (irAE) included liver damage in 4 patients, skin damage in 4 patients, thyroid dysfunction in 2 patients and lung damage in 1 patient. The median age of the IO+IO group was 79 years, with 3 patients of unresectable disease and 6 patients of recurrence. A median of 2 courses of treatment were performed, and the best overall response rate was 71.4% including CR in 4 patients, PR in 1 patient, SD in 1 patient, PD in 1 patient, and NE in 2 patients. One-year PFS was 68.6% and one-year OS was 85.7%. irAE included liver damage in 3 patients, skin damage in 6 patients, thyroid dysfunction in 2 patients, rhabdomyolysis in 1 patient and hypopituitarism in 1 patient. Discussion/Conclusion Currently, in our institute, IO+C is the first choice for unresectable esophageal carcinoma, and IO+IO is selected for patients who are unresponsive or intolerant to FP, patients requiring outpatient treatment and patients with recurrent disease. Although long-term clinical outcomes will need to be examined, immunochemotherapy is very useful and it is necessary to examine the effective use of IO+C and IO+IO in the future.

Protective effects of 10 °C preservation on donor lungs with lipopolysaccharide-induced acute lung injury

ObjectivesHypothermic lung preservation at 10 °C has been recently shown to enhance quality of healthy donor lungs during ischemia. This study aims to show generalizability of the 10 °C lung preservation using an endotoxin-induced lung injury with specific focus on the benefits of post-transplant lung function and mitochondrial preservation. MethodsLipopolysaccharide (3 mg/kg) was injected intratracheally in rats to induce lung injury. Injured lungs were flushed with preservation solution and allocated to 3 groups (n = 6 each): minimum cold storage, 6-hour storage on ice (ice), and 6-hour storage at 10 °C (10 °C). Left lungs were transplanted and reperfused for 2 hours. After storage, lung tissue was used to evaluate the effects of hypothermic storage on the mitochondrial function: mitochondrial membrane potential was assessed by JC-1 staining; mitochondrial oxygen consumption was assessed using high-resolution respirometry. ResultsTwo hours after reperfusion, the oxygen tension/inspired oxygen fraction ratio from the graft was significantly greater in the 10 °C group than in the Ice group (P = .015), whereas the wet-to-dry weight ratio was significantly lower (P = .041). Levels of interleukin-8 in lung tissues were significantly lower in the 10 °C group than in the Ice group (P = .004). Mechanistically, we noted greater mitochondrial membrane potential and elevated state III respiration in the 10 °C group than in the Ice group (P = .015 and P = .002, respectively), implying higher metabolic activities may be maintained during 10 °C preservation. ConclusionsFavorable metabolism during 10 °C preservation prevented ischemia-induced mitochondrial damages in injured lungs, leading to better post-transplant outcomes.

Evaluating Personalized Add-On Ayurveda Therapy in Oxygen-Dependent Diabetic COVID-19 Patients: A 60-Day Study of Symptoms, Inflammation, and Radiological Changes.

Background Effective management of both acute and post-acute sequelae of SARS-CoV-2 is essential, particularly for type 2 diabetes mellitus (T2DM) patients, who are at increased risk of severe pro-inflammatory responses and complications. Persistent symptoms and residual lung and cardiovascular damage in post-coronavirus disease (COVID-19) individuals highlight the need for comprehensive long-term treatment strategies. Conventional treatments, including Remdesivir and glucocorticoids, have limitations, suggesting that further investigation into Ayurvedic therapies could be beneficial, though controlled trials are currently limited. Objectives Evaluate the effectiveness and safety of Ayurveda with the standard of care (SOC) versus SOC in improving symptoms, moderating immune responses (interleukin-6 (IL-6), C-reactive protein (CRP), neutrophil-lymphocyte ratio (NLR), and radiological outcomes in oxygen-dependent, high-risk, non-vaccinated type 2 diabetes COVID-19 patients over 60 days, and thus addressing their heightened vulnerability to severe infections. Methods A controlled trial with 50 diabetic COVID-19 patients, aged 18-80, with an NLR of >= 4, primarily on Remdesivir, was assigned to Group 1 (Add-on Ayurveda+SOC, n=30) or Group 2 (SOC, n=20) based on their voluntary choice with follow-up on days 14, 28, and 60. Parametric outcomes in group analysis were assessed with robust regression and non-parametric outcomes with Cochran-Mantel-Haenszel, log-rank test, and chi-square tests at 95% confidence interval (CI). Results Group 1 exhibited statistically significant improvements in fever, cough, diarrhea, as well as NLR, IL-6, and CRP by 14 days, and in anosmia, loss of taste, shortness of breath, general weakness, and headache by 60 days. Though the sample size is small, notable improvements can be seen in troponin levels in Group 1 at 28 and 60 days. High-resolution computer tomography COVID-19 reporting and data system (HRCT CO-RADS) scores improved more slowly in Group 2 than in Group 1. Survival rates were 96.4% for Group 1 and 90% for Group 2. Numbers were too small for reliable comparisons at 60 days. Conclusion The add-on Ayurveda group showed a better symptomatic response, and faster normalization in inflammatory markers, including IL-6 and NLR by 14 days, and cardiac markers by 28 days. Minimal clinical and no laboratory adverse events were observed. This study supports the need for a randomized, double-blind trial.

Expression of Tenascin-C Is Upregulated in the Early Stages of Radiation Pneumonitis/Fibrosis in a Novel Mouse Model.

The lung is a major dose-limiting organ for radiation therapy (RT) for cancer in the thoracic region, and the clarification of radiation-induced lung damage (RILD) is important. However, there have been few reports containing a detailed comparison of radiographic images with the pathological findings of radiation pneumonitis (RP)/radiation fibrosis (RF). We recently reported the upregulated expression of tenascin-C (TNC), an inflammation-associated extracellular matrix molecule, in surgically resected lung tissue, and elevated serum levels were elevated in a RILD patient. Therefore, we have developed a novel mouse model of partial lung irradiation and studied it with special attention paid to the computed tomography (CT) images and immunohistological findings. The right lungs of mice (BALB/c) were irradiated locally at 30 Gy/1fr, and the following two groups were created. In Group 1, sequential CT was performed to confirm the time-dependent changes in RILD. In Group 2, the CT images and histopathological findings of the lung were compared. RP findings were detected histologically at 16 weeks after irradiation; they were also observed on the CT images from 20 weeks. The immunostaining of TNC was observed before the appearance of RP on the CT images. The findings suggest that TNC could be an inflammatory marker preceding lung fibrosis.

CD94+ natural killer cells potentiate pulmonary ischaemia-reperfusion injury.

Pulmonary ischaemia-reperfusion injury (IRI) is a major contributor to poor lung transplant outcomes. We recently demonstrated a central role of airway-centred natural killer (NK) cells in mediating IRI; however, there are no existing effective therapies for directly targeting NK cells in humans. We hypothesised that a depleting anti-CD94 monoclonal antibody (mAb) would provide therapeutic benefit in mouse and human models of IRI based on high levels of KLRD1 (CD94) transcripts in bronchoalveolar lavage samples from lung transplant patients. We found that CD94 is highly expressed on mouse and human NK cells, with increased expression during IRI. Anti-mouse and anti-human mAbs against CD94 showed effective NK cell depletion in mouse and human models and blunted lung damage and airway epithelial killing, respectively. In two different allogeneic orthotopic lung transplant mouse models, anti-CD94 treatment during induction reduced early lung injury and chronic inflammation relative to control therapies. Anti-CD94 did not increase donor antigen-presenting cells that could alter long-term graft acceptance. Lung transplant induction regimens incorporating anti-CD94 treatment may safely improve early clinical outcomes.

The Omega-6 Lipid pathway shift is associated with neutrophil influx and structural lung damage in early cysticfibrosis lung disease.

In cystic fibrosis (CF), an imbalanced lipid metabolism is associated with lung inflammation. Little is known about the role that specific lipid mediators (LMs) exert in CF lung inflammation, and whether their levels change during early disease progression. Therefore, we measured airway LM profiles of young CF patients, correlating these with disease-associated parameters. Levels of omega (ω)-3/6 PUFAs and their LM derivatives were determined in bronchoalveolar lavage fluid (BALF) of children with CF ages 1-5 using a targeted high-performance liquid chromatography-tandem mass spectrometry approach. Hierarchical clustering analysis was performed on relative LM levels. Individual relative LM levels were correlated with neutrophilic inflammation (BALF %Neu) and structural lung damage (PRAGMA-CF %Disease). Significant correlations were included in a backward multivariate linear regression model to identify the LMs that are best related to disease progression. A total of 65 BALF samples were analysed for ω-3/6 lipid content. LM profiles clustered into an arachidonic acid (AA)-enriched and a linoleic acid (LA)-enriched sample cluster. AA derivatives like 17-OH-DH-HETE, 5-HETE, 5,15-diHETE, 15-HETE, 15-KETE, LTB4 and 6-trans-LTB4 positively correlated with BALF %Neu and/or PRAGMA %Dis. Contrastingly, 9-HoTrE and the LA derivatives 9-HoDE, 9(10)-EpOME, 9(10)-DiHOME, 13-HoDE, 13-oxoODE and 12(13)-EpOME negatively correlated with BALF %Neu and/or PRAGMA %Dis. 6-trans-LTB4 was the strongest predictor for BALF %Neu. 5-HETE and 15-KETE contributed most to PRAGMA %Dis prediction. Our data provide more insight into the lung lipidome of infants with CF, and show that a shift from LA derivatives to AA derivatives in BALF associates with early CF lung disease progression.

Identification and Quantification of Precursory Changes of Rheumatoid Vasculitis in the Dorsalis Pedis Artery

ObjectiveRheumatoid arthritis (RA) is a systemic connective tissue autoimmune disease that can infiltrate arterial walls. The delay in diagnosis and treatment of rheumatoid vasculitis (RV) in patients with RA may lead to irreversible damage to the arterial walls of small-to-medium vessels, which has serious and devastating consequences, most notably lung and cardiac damage. In this work an ultrasound image-based biomarker was developed to detect precursory changes in RV. MethodsThe ground truth was initiated from a medical diagnosis of RA, with arterial wall thickening of the proximal dorsalis pedis artery (DPA) indicating precursory changes of RV identified with ultrasound scanning. Ultrasound images of the DPA from 49 healthy subjects in the control group and 46 patients in the RA group were obtained. In total, 187 texture features were extracted from the images, followed by principal component analysis and linear discriminant analysis. ResultsThe proposed biomarker detected a significant difference between the two groups (p = 5.74 × 10-18) with an area under the receiver operating characteristic curve of 0.85. Ten major textural features contributing most heavily to the biomarker were identified, with these textures being consistent with clinical observations of RV identified in previous studies. Interscan reproducibility was assessed by computing the biomarker twice based on repeated scans of each ankle. High interscan reproducibility was demonstrated by a strong and significant Pearson's coefficient (r = 0.85, p < 0.01) between the two repeated measurements of the proposed biomarker. ConclusionThe proposed biomarker can discriminate image textural differences seen in images acquired from RA patients, demonstrating precursory changes in RV compared with healthy controls. The major discriminative features identified in this study may facilitate the early identification and treatment of RV.

Therapeutic effects of Tocilizumab on COVID-19

Critical lung damage and death are the most profound outcomes associated with the cytokine storm induced by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It is well known that COVID-19 in many patients triggers hyperactivation of the immune system, resulting in the release of a diverse set of cytokine signal molecules in the pulmonary tissue, leading to a potentially lethal hyperinflammatory condition. One cytokine found to play a central role in this outcome is interleukin-6 (IL-6). Therefore, preventing IL-6 signaling could potentially improve patient outcomes. Tocilizumab is an IL-6 receptor agonist originally approved by the FDA to treat rheumatoid arthritis, which was found to be effective at reducing the mortality of patients with moderate to severe COVID-19 symptoms through prevention of the aforementioned induced cytokine storm. Clinical trials have supported this conclusion and will be addressed, such as the RECOVERY and COVACTA trials. Results have shown a decrease in mortality, as well as an increase in discharge rate. Future research is needed to elucidate the molecular mechanisms as well as the therapeutic roles of Tocilizumab on COVID-19 and similar pneumonia by virus infections.

Treatment with lipoxin A4 improves influenza A infection outcome, induces macrophage reprogramming, anti-inflammatory and pro-resolutive responses.

Influenza A is a virus from theOrthomixoviridaefamily responsible for high lethality rates and morbidity, despite clinically proven vaccination strategies and some anti-viral therapies. The eicosanoid Lipoxin A4 (LXA4) promotes the resolution of inflammation by decreasing cell recruitment and pro-inflammatory cytokines release, but also for inducing activation of apoptosis, efferocytosis, and macrophage reprogramming. Here, we evaluated whether a synthetic lipoxin mimetic, designated AT-01-KG, would improve the course of influenza A infection in a murine model. Mice were infected with influenza A/H1N1 and treated with AT-01-KG (1.7μg/kg/day, i.p.) at day 3 post-infection. AT-01-KG attenuated mortality, reducing leukocyte infiltration and lung damage at day 5 and day 7 post-infection. AT-01-KG is a Formyl Peptide Receptor 2 (designated FPR2/3 in mice) agonist, and the protective responses were not observed in fpr2/3-/-animals. In mice treated with LXA4(50μg/kg/day, i.p., days 3-6 post-infection), at day 7, macrophage reprogramming was observed, as seen by a decrease in classically activated macrophages and an increase in alternatively activated macrophages in the lungs. Furthermore, the number of apoptotic cells and cells undergoing efferocytosis was increased in the lavage of treated mice. Treatment also modulated the adaptive immune response, increasing the number of T helper 2 cells (Th2) and regulatory T (Tregs) cells in the lungs of the treated mice. Therefore, treatment with a lipoxin A4analog was beneficial in a model of influenza A infection in mice. The drug decreased inflammation and promoted resolution and beneficial immune responses, suggesting it may be useful in patients with severe influenza.

Dietary modulation of lung lipids influences inflammatory responses to inhaled ozone

The pulmonary system represents a unique lipidomic environment as it contains cellular membrane-bound lipid species and a specialized reservoir of lipids in the airway epithelial lining fluid. As a major initial point of defense, airway lipids react to inhaled contaminants such as volatile organic compounds, oxides of nitrogen, or ozone (O3), creating lipokine signaling that is crucial for both the initiation and resolution of inflammation within the lung. Dietary modulation of eicosanoids has gained increased attention in recent years for improvements to cardiovascular health. The current study sought to examine how dietary supplementation with eicosanoid precursors (i.e, oils rich in saturated or polyunsaturated fatty acids) might alter the lung lipid composition and subsequently modify the inflammatory response to ozone inhalation. Our study demonstrated that mice fed a diet high in saturated fatty acids resulted in diet-specific changes to lung lipid profiles and increased cellular recruitment to the lung following ozone inhalation. Bioinformatic analysis revealed an ozone-dependent upregulation of several lipid species, including phosphoserine 37:5. Pathway analysis of lipid species revealed the process of lateral diffusion of lipids within membranes to be significantly altered due to ozone exposure. These results show promising data for influencing pulmonary lipidomic profiles via diet, which may provide a pragmatic therapeutic approach to protect against lung inflammation and damage following pulmonary insult.

To the question of thrombotic and hemorrhagic complications in patients with COVID-19

COVID-19 is characterized by various adverse consequences and complications, the prevention of which affects the outcome of the disease. Aim of the study was to investigate the thrombohemorrhagic events of COVID-19 infection. Material and methods. This study involved 403 patients with novel coronavirus infection; the patients were divided into 2 groups: 75 with COVID-19 complications and 328 patients without complications. Metabolic disorders, features of lung damage, comorbidity, signs of inflammation and coagulation, treatment outcomes, peculiarities of thrombotic events and hemorrhages development were studied. Results and its discussion. Thrombohemorrhagic complications of COVID-19 occurred mostly in patients with angina pectoris, coronary artery sclerosis and chronic heart failure of functional class II–III, as well as decompensated diabetes mellitus and obesity. These coronavirus infection effects are often accompanied by an increase in content of inflammatory markers such as CRP and ferritin, as well as of hypercoagulability (D-dimers). Conclusions. Manifestations of inflammatory coagulopathy in patients infected by COVID-19 increases risk of thrombohemorrhagic complications.

Efficacy of molnupiravir and interferon for the treatment of SARS-CoV-2 in golden Syrian hamster.

The mortality and hospitalization rate by COVID-19 dropped significantly currently, but its seasonal outbreaks make antiviral treatment still vital. The mortality and hospitazation rate by COVID-19 dropped significantly currently, but its seasonal ourbreaks make antiviral treatment still vital. In our study, syrian golden hamsters were treated with molnupiravir and interferons (IFNs) after SARS-CoV-2 infection. Their weight changes, pathological changes, virus replication and inflammation levels were evaluated. In the IFNs single treatment, only IFN-α group reduced viral load (p < 0.05) and virus titer in hamster lungs. The TNF-α expression decreased significantly in both IFNs treatment at 2dpi. Histological and immunofluorescence results showed lung damage in the IFNs groups were milder at 4dpi. In the molnupiravir/IFN-α combination treatment, weight loss and virus replication in lung were significantly decreased in the mono-molnupiravir group and combination group (p < 0.05), the expression of IL-6, TNF-α, IL-1β and MIP-1α also decreased significantly (p < 0.05), but the combination treatment was not more effective than the mono-molnupiravir treatment. Histological and immunofluorescence results showed the lung damage and inflammation in mono-molnupiravir and combination groups were milder. In summary, IFNs treatment had anti-inflammatory effect against SARS-CoV-2, only IFN-α showed a weak antiviral effect. Molnupiravir/IFN-α combination treatment was effective against SARS-CoV-2 but was not superior to mono-molnupiravir treatment. IFN-α could be considered for immunocompromised patients to stimulate and activate early immune responses.

Gene expression responses of CF airway epithelial cells exposed to elexacaftor/tezacaftor/ivacaftor (ETI) suggest benefits beyond improved CFTR channel function.

Gene expression responses by CF AEC exposed to ETI suggest that in addition to improving CFTR channel function, ETI is likely to increase resistance to bacterial infection by increasing levels of beta defensin 1 (hBD-1). ETI may also reduce lung damage by suppressing MMP10, and reduce airway inflammation by repressing proinflammatory cytokine secretion by AEC cells.

Crosstalk between ROS-inflammatory gene expression axis in the progression of lung disorders.

A significant number of deaths and disabilities worldwide are brought on by inflammatory lung diseases. Many inflammatory lung disorders, including chronic respiratory emphysema, resistant asthma, resistance to steroids, and coronavirus-infected lung infections, have severe variants for which there are no viable treatments; as a result, new treatment alternatives are needed. Here, we emphasize how oxidative imbalance contributes to the emergence of provocative lung problems that are challenging to treat. Endogenic antioxidant systems are not enough to avert free radical-mediated damage due to the induced overproduction of ROS. Pro-inflammatory mediators are then produced due to intracellular signaling events, which can harm the tissue and worsen the inflammatory response. Overproduction of ROS causes oxidative stress, which causes lung damage and various disease conditions. Invasive microorganisms or hazardous substances that are inhaled repeatedly can cause an excessive amount of ROS to be produced. By starting signal transduction pathways, increased ROS generation during inflammation may cause recurrent DNA damage and apoptosis and activate proto-oncogenes. This review provides information about new targets for conducting research in related domains or target factors to prevent, control, or treat such inflammatory oxidative stress-induced inflammatory lung disorders.

Yinqin Qingfei granules alleviate Mycoplasma pneumoniae pneumonia via inhibiting NLRP3 inflammasome-mediated macrophage pyroptosis.

Mycoplasma pneumoniae pneumonia (MPP) is a prevalent respiratory infectious disease in children. Given the increasing resistance of M. pneumoniae (MP) to macrolide antibiotics, the identification of new therapeutic agents is critical. Yinqin Qingfei granules (YQQFG), a Chinese patent medicine formulated specifically for pediatric MPP, lacks a clear explanation of its mechanism. The primary components of YQQFG were identified using LC-MS/MS. In vitro, RAW264.7 cells infected with MP underwent morphological examination via scanning electron microscopy. Drug-containing serum was prepared, and its intervention concentration was determined using the CCK-8 assay. The active components of YQQFG were molecularly docked with NLRP3 protein using Autodock Vina software. A RAW264.7 cell line overexpressing NLRP3 was created using lentivirus to pinpoint the target of YQQFG. In vivo, MPP model mice were established via nasal instillation of MP. Lung damage was assessed by lung index and H&E staining. Pyroptosis-associated protein levels in cells and lung tissue were measured by western blot, while interleukin (IL)-1β and IL-18 levels in cell supernatants and mouse serum were quantified using ELISA. Immunofluorescence double staining of lung tissue sections was conducted to assess the correlation between NLRP3 protein expression and macrophages. The expression of the community-acquired respiratory distress syndrome toxin (CARDS TX) was evaluated by qPCR. 25 effective components with favorable oral bioavailability were identified in YQQFG. Both in vitro and in vivo studies demonstrated that YQQFG substantially reduced the expression of the NLRP3/Caspase-1/GSDMD pathway, decreasing the release of IL-1β and IL-18, and inhibited MP exotoxin. Molecular docking indicated strong affinity between most YQQFG components and NLRP3 protein. Lentivirus transfection and immunofluorescence double staining confirmed that YQQFG significantly suppressed NLRP3 expression in macrophages, outperforming azithromycin (AZM). The combination of YQQFG and AZM yielded the optimal therapeutic effect for MPP. YQQFG mitigates inflammatory responses by suppressing NLRP3 inflammasome-mediated macrophage pyroptosis, thereby ameliorating MP-induced acute lung injury. YQQFG serves as an effective adjunct and alternative medication for pediatric MPP treatment.

Type 2 diabetes mellitus as an independent risk factor of pulmonary tuberculosis: A hospital based cross-sectional study

Background: The growing frequency of infectious and non-communicable illnesses on a global scale is primarily associated with the changing patterns observed in epidemiology. Diabetes mellitus (DM) significantly leads to the development of tuberculosis (TB) and less effective treatment outcomes if not identified early. Objective: This study aims to investigate type 2 DM as a risk factor for TB infection.Methods: Participants in this cross-sectional research study comprised DM patients who reported cough complaints at the TB treatment center and the internal medicine department of Zainoel Abidin Hospital. Random blood glucose and glycated hemoglobin (HbA1c) levels were measured in all respondents. The Chi-Square test assesses the association between DM and Pulmonary TB.Results: There are 48 DM patients with new pulmonary TB, an averageage of 53 years (SD 9.1). Most of them have symptoms of cough for more than 2 weeks (85.4%), loss of body weight (77.1%), chest pain (58.3%), and loss of appetite (72.9%). The high HbA1c levels were associated with TB, as detected by Xpert MTB/RIF assay and typical radiographic signs (p&lt;0.05). DM patients with increased HbA1c were found to have a two times chance of showing results from a chest x-ray typical of TB and probability of TB infection (PR: 2.850, 95% CI (1.152-7.053); 2.745, 95% CI (0.969-7.780)) respectively.Conclusion: DM patients had two times the risk of lung damage based on chest X-rays and having TB. DM may seriously compromise the efficacy of TB control programs and impede a nation's progress toward TB elimination.

Lung megakaryocytes engulf inhaled airborne particles to promote intrapulmonary inflammation and extrapulmonary distribution

Many lung immune cells are known to respond to inhaled particulate matter. However, current known responses cannot explain how particles induce thrombosis in the lung and how they translocate to distant organs. Here, we demonstrate that lung megakaryocytes (MKs) in the alveolar and interstitial regions display location-determined characteristics and act as crucial responders to inhaled particles. They move rapidly to engulf particles and become activated with upregulation in inflammatory responses and thrombopoiesis. Comprehensive in vivo, in vitro and ex vivo results unraveled that MKs were involved in particle-induced lung damages and shed particle-containing platelets into blood circulation. Moreover, MK-derived platelets exhibited faster clotting, stronger adhesion than normal resting platelets, and inherited the engulfed particles from parent MKs to assist in extrapulmonary particle transportation. Our findings collectively highlight that the specific responses of MKs towards inhaled particles and their roles in facilitating the translocation of particles from the lungs to extrapulmonary organs for clearance.

Bone marrow mesenchymal stromal cells attenuate smoke inhalation injury by regulating the M1/M2-Th17/Treg immune homeostasis axis

Smoke inhalation injury (SII) is the leading cause of death in fire burn patients. The inflammatory response induced by smoke inhalation is a significant factor in the development of acute lung injury or acute respiratory distress syndrome (ALI/ARDS). Mesenchymal stem cells (MSCs) can alleviate various inflammatory diseases by regulating the polarization of macrophages from the M1 to the M2 phenotype. Moreover, MSCs can facilitate the inflammatory response by regulating Th17/Treg homeostasis. However, little is known about the associations among MSCs, M1/M2 macrophages and Th17/Treg homeostasis. Therefore, the purpose of this study was to evaluate whether MSCs affect subsequent Th17/Treg differentiation and immune homeostasis by regulating M1/M2 polarization in SII. Our results showed that bone marrow mesenchymal stem cells (BMSCs) ameliorated lung inflammatory injury and fibrosis after SII by affecting the polarization of alveolar macrophages (AMs) from the M1 to the M2 phenotype. Moreover, BMSCs maintain Th17/Treg immune homeostasis by increasing the proportion of Treg cells and decreasing the proportion of Th17 cells. In vitro, we further demonstrated that BMSCs promoted the polarization of AMs from the M1 to the M2 phenotype and decreased IL-23 levels. Reduced IL-23 decreased Th17 differentiation and promoted Th17/Treg balance. Therefore, BMSCs ameliorate the inflammatory response and lung damage after SII through regulating M1/M2 polarization and subsequent Th17/Treg immune homeostasis, which are linked to alveolar macrophage-derived IL-23. These findings provide novel insight into how BMSCs regulate the M1/M2-Th17/Treg immune homeostasis axis and provide new therapeutic targets for more effective control of the inflammatory response after SII.

Premature aging effects on COVID-19 pathogenesis: new insights from mouse models

Aging is identified as a significant risk factor for severe coronavirus disease-2019 (COVID-19), often resulting in profound lung damage and mortality. Yet, the biological relationship between aging, aging-related comorbidities, and COVID-19 remains incompletely understood. This study aimed to elucidate the age-related COVID19 pathogenesis using an Hutchinson-Gilford progeria syndrome (HGPS) mouse model, a premature aging disease model, with humanized ACE2 receptors. Pathological features were compared between young, aged, and HGPS hACE2 mice following SARS-CoV-2 challenge. We demonstrated that young mice display robust interferon response and antiviral activity, whereas this response is attenuated in aged mice. Viral infection in aged mice results in severe respiratory tract hemorrhage, likely contributing a higher mortality rate. In contrast, HGPS hACE2 mice exhibit milder disease manifestations characterized by minor immune cell infiltration and dysregulation of multiple metabolic processes. Comprehensive transcriptome analysis revealed both shared and unique gene expression dynamics among different mouse groups. Collectively, our studies evaluated the impact of SARS-CoV-2 infection on progeroid syndromes using a HGPS hACE2 mouse model, which holds promise as a useful tool for investigating COVID-19 pathogenesis in individuals with premature aging.

TARGETED TEMPERATURE MANAGEMENT AT 36°C IMPROVES SURVIVAL AND PROTECTS TISSUES BY MITIGATING THE DELETERIOUS INFLAMMATORY RESPONSE FOLLOWING HEMORRHAGIC SHOCK.

Hemorrhagic shock (HS) is a life-threatening condition with high mortality rates despite current treatments. This study investigated whether targeted temperature management (TTM) could improve outcomes by modulating inflammation and protecting organs following HS. Using a rat model of HS, TTM was applied at 33°C and 36°C after fluid resuscitation. Surprisingly, TTM at 33°C increased mortality, while TTM at 36°C significantly improved survival rates. It also reduced histological damage in lung and kidney tissues, lowered serum lactate levels, and protected against apoptosis and excessive reactive oxygen species production. TTM at 36°C inhibited the release of high mobility group box 1 protein (HMGB1), a key mediator of inflammation, and decreased proinflammatory cytokine levels in the kidneys and lungs. Moreover, it influenced macrophage behavior, suppressing the harmful M1 phenotype while promoting the beneficial M2 polarization. Cytokine array analysis confirmed reduced levels of proinflammatory cytokines with TTM at 36°C. These results collectively highlight the potential of TTM at 36°C as a therapeutic approach to improve outcomes in HS. By addressing multiple aspects of injury and inflammation, including modulation of macrophage responses and cytokine profiles, TTM at 36°C offers promising implications for critical care management after HS, potentially reducing mortality and improving patient recovery.