The Impact of Immunosenescence on Pulmonary Disease

Correlation between elderly patients with COPD and the impact on immunity in tuberculosis patients: A retrospective study

The prevalence of chronic obstructive pulmonary disease (COPD) and tuberculosis (TB) is increasing globally, yet their comprehensive impact on the immune system remains underexplored. This study aimed to provide a thorough assessment of the immune status of patients with COPD and tuberculosis (TB-COPD), including their pulmonary conditions, immune cell responses, and changes in lymphocyte subpopulations. A total of 151 patients with TB-COPD patients were included, and clinical data were compared between the TB-COPD group and a group of TB patients without COPD (TB-NCOPD). Lung imaging findings and peripheral blood immune cell levels were compared between the 2 groups. Flow cytometry was used to analyze the absolute counts of lymphocyte subpopulations. The incidence of pulmonary lobe lesions and cavitation in the TB-COPD group aged 70 years or older was significantly higher than that in the control group. At the immune cell level, patients with TB-COPD showed a significant reduction in total lymphocytes, CD4+ T lymphocytes and CD4+/CD8+ ratio. Regardless of COPD status, the CD4+ T cell count in the CMV-infected group was significantly lower than that in the uninfected group (P < .05). Additionally, the CD4+/CD8+ ratio in the COPD + TB CMV + group was significantly lower than that in the uninfected group. Analysis of lymphocyte subpopulations revealed a decrease in the counts of CD4+ T lymphocytes in patients with TB-COPD, potentially associated with the chronic inflammatory state induced by COPD. The one-month treatment outcomes showed that the improvement rate in the control group was 70.58%, which was significantly higher than the 38.92% in the COPD + TB group (P < .001). We observed a significant increase in the number of pulmonary cavity patients in the TB-COPD group, suggesting that COPD may be a potential risk factor for the formation of pulmonary cavities in patients with TB. At the immune cell level, TB-COPD patients showed a notable decrease in lymphocytes and CD4+ T lymphocytes, implying that COPD combined with pulmonary TB may significantly affect the immune system, leading to a reduction in the counts of key immune cells.

IL-10 deficiency aggravates cell senescence and accelerates BLM-induced pulmonary fibrosis in aged mice via PTEN/AKT/ERK pathway

BACKGROUND

Pulmonary fibrosis (PF) is an aging-related progressive lung disorder. The aged lung undergoes functional and structural changes termed immunosenescence and inflammaging, which facilitate the occurrence of fibrosis. Interleukin-10 (IL-10) is a potent anti-inflammatory and immunoregulatory cytokine, yet it remains unclear how IL-10 deficiency-induced immunosenescence participates in the development of PF.

METHODS

Firstly we evaluated the susceptibility to fibrosis and IL-10 expression in aged mice. Then 13-month-old wild-type (WT) and IL-10 knockout (KO) mice were subjected to bleomycin(BLM) and analyzed senescence-related markers by PCR, western blot and immunohistochemistry staining of p16, p21, p53, as well as DHE and SA-β-gal staining. We further compared 18-month-old WT mice with 13-month-old IL-10KO mice to assess aging-associated cell senescence and inflamation infiltration in both lung and BALF. Moreover, proliferation and apoptosis of alveolar type 2 cells(AT2) were evaluated by FCM, immunofluorescence, TUNEL staining, and TEM analysis. Recombinant IL-10 (rIL-10) was also administered intratracheally to evaluate its therapeutic potential and related mechanism. For the in vitro experiments, 10-week-old naïve pramily lung fibroblasts(PLFs) were treated with the culture medium of 13-month PLFs derived from WT, IL-10KO, or IL-10KO + rIL-10 respectively, and examined the secretion of senescence-associated secretory phenotype (SASP) factors and related pathways.

RESULTS

The aged mice displayed increased susceptibility to fibrosis and decreased IL-10 expression. The 13-month-old IL-10KO mice exhibited significant exacerbation of cell senescence compared to their contemporary WT mice, and even more severe epithelial-mesenchymal transition (EMT) than that of 18 month WT mice. These IL-10 deficient mice showed heightened inflammatory responses and accelerated PF progression. Intratracheal administration of rIL-10 reduced lung CD45 + cell infiltration by 15%, including a 6% reduction in granulocytes and a 10% reduction in macrophages, and increased the proportion of AT2 cells by approximately 8%. Additionally, rIL-10 significantly decreased α-SMA and collagen deposition, and reduced the expression of senescence proteins p16 and p21 by 50% in these mice. In vitro analysis revealed that conditioned media from IL-10 deficient mice promoted SASP secretion and upregulated senescence genes in naïve lung fibroblasts, which was mitigated by rIL-10 treatment. Mechanistically, rIL-10 inhibited TGF-β-Smad2/3 and PTEN/PI3K/AKT/ERK pathways, thereby suppressing senescence and fibrosis-related proteins.

CONCLUSIONS

IL-10 deficiency in aged mice leads to accelerated cell senescence and exacerbated fibrosis, with IL-10KO-PLFs displaying increased SASP secretion. Recombinant IL-10 treatment effectively mitigates these effects, suggesting its potential as a therapeutic target for PF.

Global, regional, and national incidence and mortality burden of non-COVID-19 lower respiratory infections and aetiologies, 1990-2021: a systematic analysis from the Global Burden of Disease Study 2021

BACKGROUND

Lower respiratory infections (LRIs) are a major global contributor to morbidity and mortality. In 2020-21, non-pharmaceutical interventions associated with the COVID-19 pandemic reduced not only the transmission of SARS-CoV-2, but also the transmission of other LRI pathogens. Tracking LRI incidence and mortality, as well as the pathogens responsible, can guide health-system responses and funding priorities to reduce future burden. We present estimates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 of the burden of non-COVID-19 LRIs and corresponding aetiologies from 1990 to 2021, inclusive of pandemic effects on the incidence and mortality of select respiratory viruses, globally, regionally, and for 204 countries and territories.

METHODS

We estimated mortality, incidence, and aetiology attribution for LRI, defined by the GBD as pneumonia or bronchiolitis, not inclusive of COVID-19. We analysed 26 259 site-years of mortality data using the Cause of Death Ensemble model to estimate LRI mortality rates. We analysed all available age-specific and sex-specific data sources, including published literature identified by a systematic review, as well as household surveys, hospital admissions, health insurance claims, and LRI mortality estimates, to generate internally consistent estimates of incidence and prevalence using DisMod-MR 2.1. For aetiology estimation, we analysed multiple causes of death, vital registration, hospital discharge, microbial laboratory, and literature data using a network analysis model to produce the proportion of LRI deaths and episodes attributable to the following pathogens: Acinetobacter baumannii, Chlamydia spp, Enterobacter spp, Escherichia coli, fungi, group B streptococcus, Haemophilus influenzae, influenza viruses, Klebsiella pneumoniae, Legionella spp, Mycoplasma spp, polymicrobial infections, Pseudomonas aeruginosa, respiratory syncytial virus (RSV), Staphylococcus aureus, Streptococcus pneumoniae, and other viruses (ie, the aggregate of all viruses studied except influenza and RSV), as well as a residual category of other bacterial pathogens.

FINDINGS

Globally, in 2021, we estimated 344 million (95% uncertainty interval [UI] 325-364) incident episodes of LRI, or 4350 episodes (4120-4610) per 100 000 population, and 2·18 million deaths (1·98-2·36), or 27·7 deaths (25·1-29·9) per 100 000. 502 000 deaths (406 000-611 000) were in children younger than 5 years, among which 254 000 deaths (197 000-320 000) occurred in countries with a low Socio-demographic Index. Of the 18 modelled pathogen categories in 2021, S pneumoniae was responsible for the highest proportions of LRI episodes and deaths, with an estimated 97·9 million (92·1-104·0) episodes and 505 000 deaths (454 000-555 000) globally. The pathogens responsible for the second and third highest episode counts globally were other viral aetiologies (46·4 million [43·6-49·3] episodes) and Mycoplasma spp (25·3 million [23·5-27·2]), while those responsible for the second and third highest death counts were S aureus (424 000 [380 000-459 000]) and K pneumoniae (176 000 [158 000-194 000]). From 1990 to 2019, the global all-age non-COVID-19 LRI mortality rate declined by 41·7% (35·9-46·9), from 56·5 deaths (51·3-61·9) to 32·9 deaths (29·9-35·4) per 100 000. From 2019 to 2021, during the COVID-19 pandemic and implementation of associated non-pharmaceutical interventions, we estimated a 16·0% (13·1-18·6) decline in the global all-age non-COVID-19 LRI mortality rate, largely accounted for by a 71·8% (63·8-78·9) decline in the number of influenza deaths and a 66·7% (56·6-75·3) decline in the number of RSV deaths.

INTERPRETATION

Substantial progress has been made in reducing LRI mortality, but the burden remains high, especially in low-income and middle-income countries. During the COVID-19 pandemic, with its associated non-pharmaceutical interventions, global incident LRI cases and mortality attributable to influenza and RSV declined substantially. Expanding access to health-care services and vaccines, including S pneumoniae, H influenzae type B, and novel RSV vaccines, along with new low-cost interventions against S aureus, could mitigate the LRI burden and prevent transmission of LRI-causing pathogens.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care (UK).

Respiratory dysfunction in old mice could be related to inflammation and lung fibrosis induced by hyperphosphatemia

BACKGROUND

With age, lungs undergo typical changes that lead to a deterioration of respiratory function. Our aim was to assess the role of age-associated hyperphosphatemia in these changes.

METHODS

We used C57BL6 mice to study an ageing model in vivo and human lung fibroblasts were treated with a phosphate donor, beta-glycerophosphate (BGP), to explore mechanisms involved. Respiratory function was registered with a double chamber plethysmograph. Lung structure was analysed by different staining, phosphate and cytokines levels by colorimeric kits, expression of fibrosis, inflammation and ET-1 system by western blot or RT-PCR.

RESULTS

Old mice showed hyperphosphatemia, along with lung fibrosis, loss of elastin, increased expression of pro-inflammatory cytokines and impaired respiratory function. BGP induced inflammation and fibrosis in fibroblasts through the activation and binding of NFkB to the MCP-1 or FN promoters. BGP increased ECE-1 expression by inducing NFkB binding to the ECE-1 promoter. QNZ, an NFkB inhibitor, blocked these effects. When ECE-1 was inhibited with phosphoramidon, BGP-induced inflammation and fibrosis were significantly reduced, suggesting a role for ET-1 in BGP-mediated effects.ET-1 produced effects similar to those of BGP, which were also dependent on NFkB. To study the pathophysiological relevance of hyperphosphatemia in vivo, a low-P diet was administered to a group of old animals, showing an improvement in fibrosis, inflammation and respiratory function compared to old mice on a standard diet.

CONCLUSION

These results suggest that age-related hyperphosphatemia induces inflammation, fibrosis, and impaired respiratory function in old mice; these effects appear to be mediated by ET-1 and NFkB activation.

Age-dependent changes in phagocytic activity: in vivo response of mouse pulmonary antigen presenting cells to direct lung delivery of charged PEGDA nanoparticles

BACKGROUND

Current needle-based vaccination for respiratory viruses is ineffective at producing sufficient, long-lasting local immunity in the elderly. Direct pulmonary delivery to the resident local pulmonary immune cells can create long-term mucosal responses. However, criteria for drug vehicle design rules that can overcome age-specific changes in immune cell functions have yet to be established.

RESULTS

Here, in vivo charge-based nanoparticle (NP) uptake was compared in mice of two age groups (2- and 16-months) within the four notable pulmonary antigen presenting cell (APC) populations: alveolar macrophages (AM), interstitial macrophages (IM), CD103+ dendritic cells (DCs), and CD11b+ DCs. Both macrophage populations exhibited preferential uptake of anionic nanoparticles but showed inverse rates of phagocytosis between the AM and IM populations across age. DC populations demonstrated preferential uptake of cationic nanoparticles, which remarkably did not significantly change in the aged group. Further characterization of cell phenotypes post-NP internalization demonstrated unique surface marker expression and activation levels for each APC population, showcasing heightened DC inflammatory response to NP delivery in the aged group.

CONCLUSION

The age of mice demonstrated significant preferences in the charge-based NP uptake in APCs that differed greatly between macrophages and DCs. Carefully balance of the targeting and activation of specific types of pulmonary APCs will be critical to produce efficient, age-based vaccines for the growing elderly population.

Burden of respiratory syncytial virus in older adults in Taiwan: An expert perspective on knowledge gaps

The burden of respiratory syncytial virus (RSV) infection among older adults in Taiwan is not well understood due to a scarcity of published epidemiological data. Nonetheless, the increasing proportion of older adults is anticipated to translate to increased burden of RSV infection, presenting a challenge to the healthcare system. Thus, an expert meeting was convened among a panel of infectious disease specialists from Taiwan to evaluate the existing local evidence and data gaps related to RSV infection in older adults (aged ≥50 years), and propose steps to generating evidence on disease burden among this population. Overall, there are few studies on the clinical and economic burden of RSV infection in Taiwan, and existing data are limited by small sample sizes and highly selected populations. Inconsistent RSV testing practices among older adults contribute to under-diagnosis and under-reporting, driven by limitations to reimbursement policies that discourage proactive RSV testing in older adults, and the lack of appropriate, targeted RSV treatment. Crucially, the paucity of epidemiological data may perpetuate a lack of awareness of RSV among clinicians and the public, hinder investments into RSV testing at a policymaker level, and thereby impede implementation of consistent diagnostic practices, precluding a deeper understanding of RSV. To overcome these challenges, it is imperative to prioritize generation of epidemiological data to establish the burden of RSV infection among older adults in Taiwan. Such data would also support a multi-stakeholder group in assessing the impact of future RSV-related interventions, such as educational initiatives and preventative strategies including vaccines.

Exploring the Interplay between Cellular Senescence, Immunity, and Fibrosing Interstitial Lung Diseases: Challenges and Opportunities

Fibrosing interstitial lung diseases (ILDs) are characterized by the gradual and irreversible accumulation of scar tissue in the lung parenchyma. The role of the immune response in the pathogenesis of pulmonary fibrosis remains unclear. In recent years, substantial advancements have been made in our comprehension of the pathobiology driving fibrosing ILDs, particularly concerning various age-related cellular disturbances and immune mechanisms believed to contribute to an inadequate response to stress and increased susceptibility to lung fibrosis. Emerging studies emphasize cellular senescence as a key mechanism implicated in the pathobiology of age-related diseases, including pulmonary fibrosis. Cellular senescence, marked by antagonistic pleiotropy, and the complex interplay with immunity, are pivotal in comprehending many aspects of lung fibrosis. Here, we review progress in novel concepts in cellular senescence, its association with the dysregulation of the immune response, and the evidence underlining its detrimental role in fibrosing ILDs.

Oxidative Damage and Telomere Length as Markers of Lung Cancer Development among Chronic Obstructive Pulmonary Disease (COPD) Smokers

Lung cancer (LC) constitutes an important cause of death among patients with Chronic Obstructive Pulmonary Disease (COPD). Both diseases may share pathobiological mechanisms related to oxidative damage and cellular senescence. In this study, the potential value of leucocyte telomere length, a hallmark of aging, and 8-OHdG concentrations, indicative of oxidative DNA damage, as risk biomarkers of LC was evaluated in COPD patients three years prior to LC diagnosis. Relative telomere length measured using qPCR and serum levels of 8-OHdG were determined at the baseline in 99 COPD smokers (33 with LC and 66 age-matched COPD without LC as controls). Of these, 21 COPD with LC and 42 controls had the biomarkers measured 3 years before. Single nucleotide variants (SNVs) in TERT, RTEL, and NAF1 genes were also determined. COPD cases were evaluated, which showed greater telomere length (p < 0.001) and increased serum 8-OHdG levels (p = 0.004) three years prior to LC diagnosis compared to the controls. This relationship was confirmed at the time of LC diagnosis. No significant association was found between the studied SNVs in cases vs. controls. In conclusion, this preliminary study shows that longer leucocyte telomere length and increased 8-OHdG serum levels can be useful as early biomarkers of the risk for future lung cancer development among COPD patients.

Respiratory Comorbidities Associated with Bronchiectasis in Patients with Common Variable Immunodeficiency in the USIDNET Registry

BACKGROUND

Bronchiectasis is a major respiratory complication in patients with common variable immunodeficiency (CVID) and is associated with recurrent pulmonary infections. However, it is unclear whether other infections or non-infectious respiratory conditions are related to its development.

OBJECTIVE

To identify respiratory comorbidities associated with bronchiectasis in patients with CVID.

METHODS

A total of 1470 CVID patients enrolled in the USIDNET registry were included in a cross-sectional analysis. The primary outcome of our study was to determine the clinical characteristics and other respiratory conditions associated with respiratory comorbidities and physician-reported bronchiectasis.

RESULTS

One hundred ninety-seven CVID patients were noted to have bronchiectasis (13.4%). Affected patients were significantly older than patients without bronchiectasis (median age 54 years vs. 49 years, p = 0.0004). These patients also had lower serum IgA (13 mg/dL IQR 60 mg/dL vs. 28.4 mg/dL IQR 66 mg/dL, p = 0.000). Notably, chronic rhinosinusitis (OR = 1.69 95%CI 1.05-2.75), sinusitis (OR = 2.06 95%CI 1.38-3.09), pneumonia (OR = 2.70 95%CI 1.88-3.88), COPD (OR = 2.66 95%CI 1.51-4.67), and interstitial lung disease (OR = 2.34 95%CI 1.41-3.91) were independently associated with the development of bronchiectasis in this population.

CONCLUSION

These data suggest that lower and upper respiratory infections, chronic lower airway disease, and interstitial lung diseases are independently associated with bronchiectasis in CVID patients. Further study into predisposing conditions related to the development of bronchiectasis in CVID patients may allow prediction and early intervention strategies to prevent the development of this complication.

Back to the Basics: Usefulness of Naturally Aged Mouse Models and Immunohistochemical and Quantitative Morphologic Methods in Studying Mechanisms of Lung Aging and Associated Diseases

Aging-related molecular and cellular alterations in the lung contribute to an increased susceptibility of the elderly to devastating diseases. Although the study of the aging process in the lung may benefit from the use of genetically modified mouse models and omics techniques, these approaches are still not available to most researchers and produce complex results. In this article, we review works that used naturally aged mouse models, together with immunohistochemistry (IHC) and quantitative morphologic (QM) methods in the study of the mechanisms of the aging process in the lung and its most commonly associated disorders: cancer, chronic obstructive pulmonary disease (COPD), and infectious diseases. The advantage of using naturally aged mice is that they present characteristics similar to those observed in human aging. The advantage of using IHC and QM methods lies in their simplicity, economic accessibility, and easy interpretation, in addition to the fact that they provide extremely important information. The study of the aging process in the lung and its associated diseases could allow the design of appropriate therapeutic strategies, which is extremely important considering that life expectancy and the number of elderly people continue to increase considerably worldwide.

Lung-gut axis of microbiome alterations following co-exposure to ultrafine carbon black and ozone

BACKGROUND

Microbial dysbiosis is a potential mediator of air pollution-induced adverse outcomes. However, a systemic comparison of the lung and gut microbiome alterations and lung-gut axis following air pollution exposure is scant. In this study, we exposed male C57BL/6J mice to inhaled air, CB (10 mg/m3), O3 (2 ppm) or CB + O3 mixture for 3 h/day for either one day or four consecutive days and were euthanized 24 h post last exposure. The lung and gut microbiome were quantified by 16 s sequencing.

RESULTS

Multiple CB + O3 exposures induced an increase in the lung inflammatory cells (neutrophils, eosinophils and B lymphocytes), reduced absolute bacterial load in the lungs and increased load in the gut. CB + O3 exposure was more potent as it decreased lung microbiome alpha diversity just after a single exposure. CB + O3 co-exposure uniquely increased Clostridiaceae and Prevotellaceae in the lungs. Serum short chain fatty acids (SCFA) (acetate and propionate) were increased significantly only after CB + O3 co-exposure. A significant increase in SCFA producing bacterial families (Ruminococcaceae, Lachnospiraceae, and Eubacterium) were also observed in the gut after multiple exposures. Co-exposure induced significant alterations in the gut derived metabolite receptors/mediator (Gcg, Glp-1r, Cck) mRNA expression. Oxidative stress related mRNA expression in lungs, and oxidant levels in the BALF, serum and gut significantly increased after CB + O3 exposures.

CONCLUSION

Our study confirms distinct gut and lung microbiome alterations after CB + O3 inhalation co-exposure and indicate a potential homeostatic shift in the gut microbiome to counter deleterious impacts of environmental exposures on metabolic system.

Hospital admission decisions for older Veterans with community-onset pneumonia: An analysis of 118 U.S. Veterans Affairs Medical Centers

OBJECTIVES

Age is important for prognosis in community-onset pneumonia, but how it influences admission decisions in the emergency department (ED) is not well characterized. Using clinical data from the electronic health record in a national cohort, we examined pneumonia hospitalization patterns, variation, and relationships with mortality among older versus younger Veterans.

METHODS

In a retrospective cohort of patients ≥ 18 years presenting to EDs with a diagnosis of pneumonia at 118 VA Medical Centers January 1, 2006, to December 31, 2016, we compared observed, predicted, and residual hospitalization risk for Veterans < 70, 70-79, and ≥ 80 years of age using generalized estimating equations and machine learning models with 71 patient factors. We examined facility variation in residual hospitalization across facilities and explored whether facility differences in hospitalization risk correlated with differences in 30-day mortality.

RESULTS

Among 297,498 encounters, 165,003 (55%) were for Veterans < 70 years, 61,076 (21%) 70-80, and 71,419 (24%) ≥ 80. Hospitalization rates were 52%, 67%, and 76%, respectively. After other patient factors were adjusting for, age 70-79 had an odds ratio (OR) of 1.39 (95% confidence interval [CI] 1.34-1.44) and ≥ 80 had an OR of 2.1 (95% CI 2.0-2.2) compared to age < 70. There was substantial variation in hospitalization across facilities among Veterans < 70 (<35% hospitalization at the lowest decile of facilities vs. > 66% at the highest decile) that was similar but with higher risk for patients 70-79 years (54% vs. 82%) and ≥ 80 years (59% vs. 85%) and remained after accounting for patient factors, with no consistently positive or negative associations with facility-level 30-day mortality.

CONCLUSIONS

Older Veterans with community-onset pneumonia experience high risk of hospitalization, with widespread facility variation that has no clear relationship to short-term mortality.

Cigarette Smoking, and Blood Monocyte Count Correlate with Chronic Lung Injuries and Mortality

Background

Cigarette smoking (CS)-related monocytosis contributes to the development of chronic lung injuries via complex mechanisms. We aim to determine correlations between measures of CS and monocytes, their capacities to predict chronic lung diseases, and their associations with mortality.

Methods

A single-center retrospective study of patients undergoing surgical resection for suspected lung nodules/masses was performed. CS was quantified as cigarettes smoked per day (CPD), duration of smoking, composite pack years (CPY), current smoking status, and smoking cessation years. A multivariate logistic regression analysis was performed.

Results

Of 382 eligible patients, 88% were ever smokers. In this group, 45% were current smokers with mean CPD of 27.2±40.0. CPY and duration of smoking showed positive linear correlations with percentage monocyte count. Physiologically, CPY was associated with progressive obstruction, hyperinflation, and reduced diffusion capacity (DL_CO). Across the quartiles of smoking, there was an accumulation of radiologic and histologic abnormalities. Anthracosis and emphysema were associated with CPD, while lung cancer, respiratory bronchiolitis (RB), emphysema, and honeycombing were statistically related to duration of smoking. Analysis using consecutive CPY showed associations with lung cancer (≥10 and <30), fibrosis (≥20 and <40), RB (≥50), anthracosis and emphysema (≥10 and onwards). Percentage monocytes correlated with organizing pneumonia (OP), fibrosis, and emphysema. The greater CPY increased mortality across the groups. Significant predictors of mortality included percentage monocyte, anemia, GERD, and reduced DL_CO.

Conclusion

Indices of CS and greater monocyte numbers were associated with endpoints of chronic lung disease suggesting a participation in pathogenesis. Application of these easily available metrics may support a chronology of CS-induced chronic lung injuries. While a relative lesser amount of smoking can be associated with lung cancer and fibrosis, greater CPY increases the risk for emphysema. Monocytosis predicted lung fibrosis and mortality. Duration of smoking may serve as a better marker of monocytosis and associated chronic lung diseases.

Applying Next-Generation Sequencing and Multi-Omics in Chronic Obstructive Pulmonary Disease

Microbiomics have significantly advanced over the last decade, driven by the widespread availability of next-generation sequencing (NGS) and multi-omic technologies. Integration of NGS and multi-omic datasets allow for a holistic assessment of endophenotypes across a range of chronic respiratory disease states, including chronic obstructive pulmonary disease (COPD). Valuable insight has been attained into the nature, function, and significance of microbial communities in disease onset, progression, prognosis, and response to treatment in COPD. Moving beyond single-biome assessment, there now exists a growing literature on functional assessment and host-microbe interaction and, in particular, their contribution to disease progression, severity, and outcome. Identifying specific microbes and/or metabolic signatures associated with COPD can open novel avenues for therapeutic intervention and prognosis-related biomarkers. Despite the promise and potential of these approaches, the large amount of data generated by such technologies can be challenging to analyze and interpret, and currently, there remains a lack of standardized methods to address this. This review outlines the current use and proposes future avenues for the application of NGS and multi-omic technologies in the endophenotyping, prognostication, and treatment of COPD.

Early differentiated CD28+ CD27+ T lymphocytes as a biomarker for short and long-term outcomes in older patients with pneumonia

This study tested the hypothesis that a more senescent immune system would predict a worse outcome in older patients hospitalized for community-acquired pneumonia (CAP). CAP has long been responsible for high rates of mortality and readmissions among older people. Although immunosenescence is a key factor in the increased susceptibility to infections, there are no related biomarkers currently available in clinical practice. In this context, the aim of this prospective study was to identify immunosenescence-related biomarkers to predict outcomes in patients older than 65 years hospitalized for CAP. We evaluated 97 patients admitted to our hospital for CAP in 2019 and 2020. All patients were followed for 1 year. Our findings showed that elevated levels of early differentiated CD28⁺ CD27⁺ T cells at admission were associated with better short (2 months) and long-term (1 year) outcomes in terms of mortality and readmissions. Early differentiated CD28⁺ CD27⁺ CD4⁺ T cell counts were even better long-term predictors. In conclusion, early differentiated CD28⁺ CD27⁺ T cells could be useful biomarkers to identify high-risk older patients with CAP, helping clinicians with risk stratification and follow-up.

COVID-19 and PIMS-Two Different Entities, but the Same Trigger

COVID-19 and PIMS represent two novel pathologies that have challenged the medical world during the last two years on account of their being very similar, but yet very different. Our aim was to comparatively assess children with SARS-CoV-2 infection and PIMS in terms of symptoms, clinical findings, laboratory parameters, echocardiography, and evolution. Our retrospective study included 46 children with COVID-19 (group 1), and 20 children with confirmed PIMS (group 2). We found no significant differences in terms of age, gender, and originating area between the two groups. We noticed that fever was significantly more common in the PIMS group as compared to COVID-19 group (p = 0.0217). In terms of laboratory parameters, increased bilirubin and creatinine were significantly more frequent in children with COVID-19 (p = 0.0064/p = 0.0064), while hypoalbuminemia and elevated ESR were significantly more common in those with PIMS (p < 0.0001/p = 0.0127). Moreover, prognosis parameters such as D-dimers, NT-proBNP, and CK-MB were also found to be significantly higher in the PIMS group as compared to COVID-19 group (p = 0.0003/p = 0.0182/p = 0.0007). In terms of complications, most were identified in PIMS group, among which cardiac and liver impairment along with dehydration were significantly more common in children diagnosed with PIMS as compared to those detected with COVID-19. Similarly, children with PIMS had a significantly higher chance to have pathological echocardiography changes. Although difficult, the distinction between COVID-19 and PIMS is crucial for the patient’s long-term outcome.

Endothelial dysfunction: The possible link between cardiovascular comorbidities and phenomenon of inflammaging from COPD

Aging is a risk factor for many chronic noncommunicable diseases, including chronic obstructive pulmonary disease (COPD), which is often associated with cardiovascular disease (CVD). Moreover, aging is associated with a mild form of systemic inflammation. The aim of our study was to analyze the relationship between age, systemic and vascular inflammation, and the presence of CVD comorbidities in a stable COPD population. Forty COPD patients were divided into 2 age groups (<65 and ≥65 years of age), from which we collected the following inflammatory biomarkers: C-reactive protein, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and endothelin-1 (ET-1). Elderly COPD patients had more frequent exacerbation events per year (2 vs 1, P = .06), a higher prevalence of CVD (3 vs 2, P = .04), more limited exercise tolerance (6-minute walking test distance, 343 [283-403] vs 434 [384-484]; P = .02), and mild systemic inflammation (TNF-α, 9.02 [7.08-10.96] vs 6.48 [5.21-7.76]; P = .03; ET-1, 2.24 [1.76-2.71] vs 1.67 [1.36-1.98] pg/mL; P = .04). A weak correlation between age and ET-1 (r = 0.32, P = .04) was observed. Mild systemic inflammation, characterized by a slightly increased level of TNF-α, and endothelial dysfunction, marked by elevated ET-1, could be liaisons between aging, COPD, and CVD comorbidities.

Decreased Levels of SARS-CoV-2 Fusion-Inhibitory Antibodies in the Serum of Aged COVID-19 Patients

Background: The SARS-CoV-2 pandemic was particularly devastating for elderly people, and the underlying mechanisms of the disease are still poorly understood. In this study, we investigated fusion inhibitory antibodies (fiAbs) in elderly and younger COVID-19 patients and analyzed predictive factors for their occurrence. Methods: Data and samples were collected in two cohorts of hospitalized patients. A fusion assay of SARS-CoV-2 spike-expressing cells with ACE2-expressing cells was used to quantify fiAbs in the serum of patients. Results: A total of 108 patients (52 elderly (mean age 85 ± 7 years); 56 young (mean age 52 ± 10 years)) were studied. The concentrations of fiAbs were lower in geriatric patients, as evidenced at high serum dilutions (1/512). The association between fiAbs and anti-Spike Ig levels was weak (correlation coefficient < 0.3), but statistically significant. Variables associated with fusion were the delay between the onset of symptoms and testing (HR = −2.69; p < 0.001), clinical frailty scale (HR = 4.71; p = 0.035), and WHO severity score (HR = −6.01, p = 0.048). Conclusions: Elderly patients had lower fiAbs levels after COVID-19 infection. The decreased fiAbs levels were associated with frailty.

Immunosenescence in Childhood Cancer Survivors and in Elderly: A Comparison and Implication for Risk Stratification

The population of childhood cancer survivors (CCS) has grown rapidly in recent decades. Although cured of their original malignancy, these individuals are at increased risk of serious late effects, including age-associated complications. An impaired immune system has been linked to the emergence of these conditions in the elderly and CCS, likely due to senescent immune cell phenotypes accompanied by low-grade inflammation, which in the elderly is known as "inflammaging." Whether these observations in the elderly and CCS are underpinned by similar mechanisms is unclear. If so, existing knowledge on immunosenescent phenotypes and inflammaging might potentially serve to benefit CCS. We summarize recent findings on the immune changes in CCS and the elderly, and highlight the similarities and identify areas for future research. Improving our understanding of the underlying mechanisms and immunosenescent markers of accelerated immune aging might help us to identify individuals at increased risk of serious health complications.

Aging and Susceptibility to Pulmonary Disease

The lungs are continually subjected to noxious and inert substances, are immunologically active, and are in a constant state of damage and repair. This makes the pulmonary system particularly vulnerable to diseases of aging. Aging can be understood as random molecular damage that is unrepaired and accumulates over time, resulting in cellular defects and tissue dysfunction. The breakdown of cellular mechanisms, including stem cell exhaustion, genomic instability, telomere attrition, epigenetic alteration, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, altered intercellular communication, and changes in the extracellular matrix is thought to advance the aging process itself. Chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and cancers illustrate a pathologic breakdown in these mechanisms beyond normal aging. The immune system becomes less effective with advancing age. There is a low-level state of chronic inflammation termed inflammaging which is thought to be driven by immunosenescence, the changes in the innate and adaptive immune systems with advancing age that lead to dysregulation and decreased effectiveness of the immune system. These processes of aging lead to expected changes in the form and function of the respiratory system, most notably a loss of lung elasticity, decrease in respiratory muscle strength, increase in ventilation-perfusion mismatching, and stiffening of the vasculature. The astute clinician is aware of these expected findings and does not often attribute dyspnea to aging alone. Maintaining a low threshold to investigate for comorbid disease and understanding how pulmonary disease presents differently in the elderly than in younger adults can improve clinical outcomes. © 2022 American Physiological Society. Compr Physiol 12:3509-3522, 2022.

Identification of healthspan-promoting genes in Caenorhabditis elegans based on a human GWAS study

To find drivers of healthy ageing, a genome-wide association study (GWAS) was performed in healthy and unhealthy older individuals. Healthy individuals were defined as free from cardiovascular disease, stroke, heart failure, major adverse cardiovascular event, diabetes, dementia, cancer, chronic obstructive pulmonary disease (COPD), asthma, rheumatism, Crohn’s disease, malabsorption or kidney disease. Six single nucleotide polymorphisms (SNPs) with unknown function associated with ten human genes were identified as candidate healthspan markers. Thirteen homologous or closely related genes were selected in the model organism C. elegans for evaluating healthspan after targeted RNAi-mediated knockdown using pathogen resistance, muscle integrity, chemotaxis index and the activity of known longevity and stress response pathways as healthspan reporters. In addition, lifespan was monitored in the RNAi-treated nematodes. RNAi knockdown of yap-1, wwp-1, paxt-1 and several acdh genes resulted in heterogeneous phenotypes regarding muscle integrity, pathogen resistance, chemotactic behaviour, and lifespan. Based on these observations, we hypothesize that their human homologues WWC2, CDKN2AIP and ACADS may play a role in health maintenance in the elderly.

Ongoing Clinical Trials in Aging-Related Tissue Fibrosis and New Findings Related to AhR Pathways

Fibrosis is a pathological manifestation of wound healing that replaces dead/damaged tissue with collagen-rich scar tissue to maintain homeostasis, and complications from fibrosis contribute to nearly half of all deaths in the industrialized world. Ageing is closely associated with a progressive decline in organ function, and the prevalence of tissue fibrosis dramatically increases with age. Despite the heavy clinical and economic burden of organ fibrosis as the population ages, to date, there is a paucity of therapeutic strategies that are specifically designed to slow fibrosis. Aryl hydrocarbon receptor (AhR) is an environment-sensing transcription factor that exacerbates aging phenotypes in different tissues that has been brought back into the spotlight again with economic development since AhR could interact with persistent organic pollutants derived from incomplete waste combustion. In addition, gut microbiota dysbiosis plays a pivotal role in the pathogenesis of numerous diseases, and microbiota-associated tryptophan metabolites are dedicated contributors to fibrogenesis by acting as AhR ligands. Therefore, a better understanding of the effects of tryptophan metabolites on fibrosis modulation through AhR may facilitate the exploitation of new therapeutic avenues for patients with organ fibrosis. In this review, we primarily focus on how tryptophan-derived metabolites are involved in renal fibrosis, idiopathic pulmonary fibrosis, hepatic fibrosis and cardiac fibrosis. Moreover, a series of ongoing clinical trials are highlighted.

Kinetics of inflammatory biomarkers to predict one-year mortality in older patients hospitalized for pneumonia: a multivariable analysis

OBJECTIVES

Long-term mortality is increased in older patients with pneumonia. We aimed to test whether residual inflammation is predictive of one-year mortality after pneumonia.

METHODS

Inflammation biomarkers (C-reactive protein [CRP], interleukin [IL]-6 and IL-8, tumor necrosis factor-α, serum amyloid A, neopterin, myeloperoxidase, anti-apolipoprotein A-1, and anti-phosphorylcholine IgM) were measured at admission and discharge in older patients hospitalized for pneumonia in a prospective study. Univariate and multivariate analyses were conducted using absolute level at discharge and relative and absolute differences between admission and discharge for all biomarkers, along with usual prognostic factors.

RESULTS

In the 133 included patients (median age, 83 years [interquartile range: 78-89]), one-year mortality was 26%. In univariate analysis, the relative difference of CRP levels had the highest area under the receiver operating characteristic curve (0.70; 95% confidence interval [CI] 0.60-0.80). A decrease of CRP levels of more than 67% between admission and discharge had 68% sensitivity and 68% specificity to predict survival. In multivariate analysis, lower body mass index (hazard ratio=0.87 [CI 95% 0.79-0.96], P-value=0.01), higher IL-8 (hazard ratio=1.02 [CI 95% 1.00-1.04], P-value=0.02), and higher CRP (1.01 [95% CI 1.00-1.02], P=0.01) at discharge were independently associated with mortality.

CONCLUSION

Higher IL-8 and CRP levels at discharge were independently associated with one-year mortality. The relative CRP difference during hospitalization was the best individual biomarker for predicting one-year mortality.

Immunosenescence, immune fitness and vaccination schedule in the adult respiratory patient

Immunosenescence is the gradual deterioration of the immune system caused by advancing age. It is associated with a reduced ability to respond to infections and develop long-term immune memory. It plays a key role in the development of respiratory diseases that are more common in older people, such as asthma, COPD, diffuse interstitial disease and respiratory infections in the elderly.

We call immune fitness the establishment of lifestyle habits that can improve our immune capacity. We now know that good eating habits, good social relationships, not smoking, limiting alcohol consumption, exercising, controlling stress levels and establishing a proper vaccination programme can slow down the process of immunosenescence.

Influenza and pneumococcal vaccines (PCV13 and PPSV23 conjugate) are well established in the adult vaccination schedule. The new pneumococcal vaccines PCV15 and PCV20 will help to extend protection against pneumococcal disease in adults. The vaccine against COVID-19 is currently the most useful tool to prevent the disease and reduce its pathogenicity. COPD patients and others with respiratory diseases may benefit from prevention of herpes zoster and Bordetella pertussis through vaccination. Respiratory syncytial virus (RSV) vaccine may be another vaccine to be added to the schedule, pending the results of its studies.

Pediatric COVID-19: Low Incidence, but Possible Fatality—A Case Report and a Review of the Literature

Background: Pediatric COVID-19 is a current health burden mostly due to the lack of knowledge in terms of symptoms, clinical course and management. COVID-19-associated coagulopathy is one of the most recently described complications among adults, along with acquired thrombophilia resulting in an increased risk for venous, arterial and microvascular thrombosis. Case presentation: We report the case of a 4-year-old male child, admitted to our clinic for generalized seizures being intubated and mechanically ventilated before admission, with a personal history of ureterovesical junction obstruction, mild hydronephrosis, and an episode of generalized seizures. The laboratory tests revealed anemia, an increased number of monocytes, and a mildly increased C-reactive protein. A real-time polymerase chain reaction (RT-PCR) of the oropharyngeal swab was performed and it tested positive for SARS-CoV-2 in the child and both of his parents. The thoracic CT showed consolidation in the lower lobe of the left lung associated with an opacity in the right apex, suggesting possible atelectasis. We initiated antibiotic, antiviral, corticosteroids, as well as anticoagulants and antipyretics, continuing the chronic anticonvulsant therapy. The patient’s condition deteriorated progressively, and, after 72 h of hospitalization, he developed desaturation and bradycardia. The laboratory parameters on the third day showed leucopenia, neutropenia, increased creatine kinase, a high ferritin level, hypoalbuminemia, a prolonged prothrombin time and an increased international normalized ration. The patient died on the fourth day of admission. Conclusion: In spite of its low incidence and frequent benign clinical course, COVID-19 complications such as coagulopathy might represent a leading cause of death, even in pediatric patients.

Aging Immune System and Its Correlation With Liability to Severe Lung Complications

Aging is considered to be a decline in physical and physiological events that extensively affect the body's immunity, and is linked with deterioration in both innate and adaptive immune responses. The immune system exhibits profound age-associated variations, known as immunosenescence, comprising a significantly low production of B and T lymphocytes in bone marrow and thymus, a decreased function of mature lymphocytes in secondary lymphoid tissues, a decrease in the synthesis of fresh naïve T cells, and reduced activation of T cells. Elderly individuals face a greater risk for many diseases particularly respiratory diseases due to their poor response to immune challenges as vigorously as the young. The current review explored the aging immune system, highlight the mortality rates of severe lung complications, such as pneumonia, COVID-19, asthma, COPD, lung cancer, IPF, and acute lung injury, and their correlation with aging immunity. This study can be helpful in better understanding the pathophysiology of aging, immune responses, and developing new approaches to improve the average age of the elderly population.

Aspergillus-Associated Endophenotypes in Bronchiectasis

Bronchiectasis is a chronic condition of global relevance resulting in permanent and irreversible structural airway damage. Bacterial infection in bronchiectasis is well studied; however, recent molecular studies identify fungi as important pathogens, either independently or in association with bacteria. Aspergillus species are established fungal pathogens in cystic fibrosis and their role is now increasingly being recognized in noncystic fibrosis bronchiectasis. While the healthy airway is constantly exposed to ubiquitously present Aspergillus conidia in the environment, anatomically damaged airways appear more prone to colonization and subsequent infection by this fungal group. Aspergilli possess diverse immunopathological mechanistic capabilities and when coupled with innate immune defects in a susceptible host, such as that observed in bronchiectasis, it may promote a range of clinical manifestations including sensitization, allergic bronchopulmonary aspergillosis, Aspergillus bronchitis, and/or invasive aspergillosis. How such clinical states influence "endophenotypes" in bronchiectasis is therefore of importance, as each Aspergillus-associated disease state has overlapping features with bronchiectasis itself, and can evolve, depending on underlying host immunity from one type into another. Concurrent Aspergillus infection complicates the clinical course and exacerbations in bronchiectasis and therefore dedicated research to better understand the Aspergillus-host interaction in the bronchiectasis airway is now warranted.

Cellular Senescence: Pathogenic Mechanisms in Lung Fibrosis

Pulmonary fibrosis is a chronic and fatal lung disease that significantly impacts the aging population globally. To date, anti-fibrotic, immunosuppressive, and other adjunct therapy demonstrate limited efficacies. Advancing our understanding of the pathogenic mechanisms of lung fibrosis will provide a future path for the cure. Cellular senescence has gained substantial interest in recent decades due to the increased incidence of fibroproliferative lung diseases in the older age group. Furthermore, the pathologic state of cellular senescence that includes maladaptive tissue repair, decreased regeneration, and chronic inflammation resembles key features of progressive lung fibrosis. This review describes regulatory pathways of cellular senescence and discusses the current knowledge on the senescence of critical cellular players of lung fibrosis, including epithelial cells (alveolar type 2 cells, basal cells, etc.), fibroblasts, and immune cells, their phenotypic changes, and the cellular and molecular mechanisms by which these cells contribute to the pathogenesis of pulmonary fibrosis. A few challenges in the field include establishing appropriate in vivo experimental models and identifying senescence-targeted signaling molecules and specific therapies to target senescent cells, known collectively as "senolytic" or "senotherapeutic" agents.

Effects of age and comorbidities on serum levels of inflammatory markers in community-acquired pneumonia

INTRODUCTION

Studies have suggested that an inappropriate inflammatory response is a major cause of treatment failure and mortality in patients with community-acquired pneumonia (CAP). We aimed to determine the effect of age and comorbidities on serum inflammatory markers in CAP.

METHODS

We performed a prospective cohort study of adults hospitalized with CAP. For the purposes of this study, we compared patients according to comorbidities and age. Inflammatory markers were measured at hospital admission, focusing on acute phase proteins, cytokines and monocyte human leucocyte antigen DR (mHLA-DR) expression.

RESULTS

In patients with chronic pulmonary disease (COPD), serum cytokines had significantly decreased levels of tumour necrosis factor (TNF)-α, interleukin (IL)-6 and mHLA-DR expression, as well as the C-reactive protein (CRP), compared with patients who had no comorbidities. Similarly, patients with chronic heart disease had a significantly reduced CRP levels and mHLA-DR expression, whereas patients with chronic kidney disease had significantly higher serum levels of procalcitonin and TNF-α. Lower procalcitonin, IL-6 and IL-10 levels, as well as mHLA-DR expression, were documented in older patients, but with no significant differences compared to younger patients. Multimorbidity in older patients was associated with significant lower levels of CRP and mHLA-DR expression.

CONCLUSIONS

The circulating inflammatory markers to CAP have profiles that differ with age and underlying comorbidities. Multimorbidity in the elderly is also associated with lower serum levels of some inflammatory markers. Our findings suggest that inflammatory markers in CAP should be interpreted after considering age and comorbid conditions.

Immunomodulation by the Commensal Microbiome During Immune-Targeted Interventions: Focus on Cancer Immune Checkpoint Inhibitor Therapy and Vaccination

Emerging evidence in clinical and preclinical studies indicates that success of immunotherapies can be impacted by the state of the microbiome. Understanding the role of the microbiome during immune-targeted interventions could help us understand heterogeneity of treatment success, predict outcomes, and develop additional strategies to improve efficacy. In this review, we discuss key studies that reveal reciprocal interactions between the microbiome, the immune system, and the outcome of immune interventions. We focus on cancer immune checkpoint inhibitor treatment and vaccination as two crucial therapeutic areas with strong potential for immunomodulation by the microbiota. By juxtaposing studies across both therapeutic areas, we highlight three factors prominently involved in microbial immunomodulation: short-chain fatty acids, microbe-associate molecular patterns (MAMPs), and inflammatory cytokines. Continued interrogation of these models and pathways may reveal critical mechanistic synergies between the microbiome and the immune system, resulting in novel approaches designed to influence the efficacy of immune-targeted interventions.

Tapping the immunological imprints to design chimeric SARS-CoV-2 vaccine for elderly population

The impact of SARS-CoV-2 and COVID-19 disease susceptibility varies depending on the age and health status of an individual. Currently, there are more than 140 COVID-19 vaccines under development. However, the challenge will be to induce an effective immune response in the elderly population. Analysis of B cell epitopes indicates the minor role of the stalk domain of spike protein in viral neutralization due to low surface accessibility. Nevertheless, the accumulation of mutations in the receptor-binding domain (RBD) might reduce the vaccine efficacy in all age groups. We also propose the concept of chimeric vaccines based on the co-expression of SARS-CoV-2 spike and influenza hemagglutinin (HA) and matrix protein 1 (M1) proteins to generate chimeric virus-like particles (VLP). This review discusses the possible approaches by which influenza-specific memory repertoire developed during the lifetime of the elderly populations can converge to mount an effective immune response against the SARS-CoV-2 spike protein with the possibilities of designing single vaccines for COVID-19 and influenza. HighlightsImmunosenescence aggravates COVID-19 symptoms in elderly individuals.Low immunogenicity of SARS-CoV-2 vaccines in elderly population.Tapping the memory T and B cell repertoire in elderly can enhance vaccine efficiency.Chimeric vaccines can mount effective immune response against COVID-19 in elderly.Chimeric vaccines co-express SARS-CoV-2 spike and influenza HA and M1 proteins.

Biomaterials-Based Opportunities to Engineer the Pulmonary Host Immune Response in COVID-19

The COVID-19 pandemic caused by the global spread of the SARS-CoV-2 virus has led to a staggering number of deaths worldwide and significantly increased burden on healthcare as nations scramble to find mitigation strategies. While significant progress has been made in COVID-19 diagnostics and therapeutics, effective prevention and treatment options remain scarce. Because of the potential for the SARS-CoV-2 infections to cause systemic inflammation and multiple organ failure, it is imperative for the scientific community to evaluate therapeutic options aimed at modulating the causative host immune responses to prevent subsequent systemic complications. Harnessing decades of expertise in the use of natural and synthetic materials for biomedical applications, the biomaterials community has the potential to play an especially instrumental role in developing new strategies or repurposing existing tools to prevent or treat complications resulting from the COVID-19 pathology. Leveraging microparticle- and nanoparticle-based technology, especially in pulmonary delivery, biomaterials have demonstrated the ability to effectively modulate inflammation and may be well-suited for resolving SARS-CoV-2-induced effects. Here, we provide an overview of the SARS-CoV-2 virus infection and highlight current understanding of the host's pulmonary immune response and its contributions to disease severity and systemic inflammation. Comparing to frontline COVID-19 therapeutic options, we highlight the most significant untapped opportunities in immune engineering of the host response using biomaterials and particle technology, which have the potential to improve outcomes for COVID-19 patients, and identify areas needed for future investigations. We hope that this work will prompt preclinical and clinical investigations of promising biomaterials-based treatments to introduce new options for COVID-19 patients.

Dysbiosis, malnutrition and enhanced gut-lung axis contribute to age-related respiratory diseases

Older people are at an increased risk of developing respiratory diseases such as chronic obstructive pulmonary diseases, asthma, idiopathic pulmonary fibrosis or lung infections. Susceptibility to these diseases is partly due to the intrinsic ageing process, characterized by genomic, cellular and metabolic hallmarks and immunosenescence, and is associated with changes in the intestinal microbiota. Importantly, in the lungs, ageing is also associated with a dysbiosis and loss of resilience of the resident microbiota and alterations of the gut-lung axis. Notably, as malnutrition is often observed in the elderly, nutrition is one of the most accessible modifiable factors affecting both senescence and microbiota. This article reviews the changes affecting the lung and its resident microbiota during ageing, as well as the interconnections between malnutrition, senescence, microbiota, gut-lung axis and respiratory health. As the communication along the gut-lung axis becomes more permissive with ageing, this review also explores the evidence that the gut and lung microbiota are key players in the maintenance of healthy lungs, and as such, are potential targets for nutrition-based preventive strategies against lung disease in elderly populations.

The effects of BMMSC treatment on lung tissue degeneration in elderly macaques

BACKGROUND

Age-associated lung tissue degeneration is a risk factor for lung injury and exacerbated lung disease. It is also the main risk factor for chronic lung diseases (such as COPD, idiopathic pulmonary fibrosis, cancer, among others). So, it is particularly important to find new anti-aging treatments.

METHODS

We systematically screened and evaluated elderly senile multiple organ dysfunction macaque models to determine whether BMMSCs inhibited lung tissue degeneration.

RESULTS

The average alveolar area, mean linear intercept (MLI), and fibrosis area in the elderly macaque models were significantly larger than in young rhesus monkeys (p < 0.05), while the capillary density around the alveoli was significantly low than in young macaque models (p < 0.05). Intravenous infusion of BMMSCs reduced the degree of pulmonary fibrosis, increased the density of capillaries around the alveoli (p < 0.05), and the number of type II alveolar epithelium in elderly macaques (p < 0.05). In addition, the infusion reduced lung tissue ROS levels, systemic and lung tissue inflammatory levels, and Treg cell ratio in elderly macaque models (p < 0.05). Indirect co-cultivation revealed that BMMSCs suppressed the expression of senescence-associated genes, ROS levels, apoptosis rate of aging type II alveolar epithelial cells (A549 cells), and enhanced their proliferation (p < 0.05).

CONCLUSIONS

BMMSC treatment inhibited age-associated lung tissue degeneration.

The Discrepancies of COVID-19 Clinical Spectrum Between Infancy and Adolescence - Two Case Reports and a Review of the Literature

A new pandemic caused by SARS-CoV-2 raised new challenges for the worldwide healthcare system, involving the pediatric field since children own certain peculiarities that caused a different reaction to this infection as compared to adults. We report two cases of COVID-19 in two pediatric patients, a 6-month-old male infant and a 15-year-old female teenager in order to underline the age-related differences in terms of clinical manifestations. Thus, the 6-month-old male infant was admitted in our clinic presenting fever, rhinorrhea and diarrhea for ~24 h. Taking into account that both parents presented respiratory manifestations, nasopharyngeal/oropharyngeal swab-based polymerase chain reaction tests for SARS-CoV-2 were performed, and the test came back positive for the parents and inconclusive for the infant. Nevertheless, the infection was confirmed also in the child by the second test. The symptoms resolved in the 2nd day of admission with symptomatic treatment. The 2nd case, a 15-year-old female teenager, presented to the emergency department with fever, cough and shortness of breath (O2 saturation 84%). The chest radiography pointed out multilobar impairment. The nasopharyngeal/oropharyngeal swab-based polymerase chain reaction test for SARS-CoV-2 infection was positive. She was admitted to the intensive care unit for 3 days, and the evolution was favorable with anti-viral therapy. The pediatrician's awareness regarding both asymptomatic and atypical cases is vital for decreasing the transmission of this novel life-threatening condition.

Coronavirus disease 2019 in children: Clinical & epidemiological implications

Despite the global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, there are limited data emerging in children. This review provides an update on clinical features, diagnosis, epidemiology, management and prevention of coronavirus disease 2019 (COVID-19) in children. Specific characteristics noted in children and their implications in disease management as well as transmission control are highlighted. Besides respiratory symptoms, gastrointestinal and atypical features such as chilblains, neurological symptoms and multisystem inflammation are also reported. Younger infants and those with comorbidity were found to be at risk of severe illness. Infected pregnant women and neonates were reported to have good prognosis. It is possible to manage the children with mild disease at home, with strict infection prevention control measures; severely affected require respiratory support and intensive care management. There are anecdotal reports of using antiviral and immunomodulatory drugs, benefit of which needs to be confirmed in clinical trials. A significant percentage of asymptomatic infection in children has epidemiological implication as these may act as links in transmission chain in the community. There is a need for systematic data on extra-pulmonary manifestations and atypical features, risk factors of severity, role of imaging and biomarkers, testing and management strategies and trials with antivirals and immunomodulatory drugs in children. The psychosocial effects of quarantine, closure of schools, lack of play activities and impact of lockdown need to be addressed. Understanding the biological basis for the profound age-dependent differential outcome of COVID-19 infection is important. Elucidating the protective mechanisms in children may aid in developing novel treatment strategies.

Caring for older adults during the COVID pandemic and beyond: experience from a specialized tertiary facility for the care of older persons in a low resource setting

The ongoing Coronavirus disease (COVID-19) pandemic has markedly changed health care provisions and arrangements for patient care. Older adults are most susceptible to worse outcomes. The public health impact of the disease in terms of morbidity and mortality has necessitated the evolution of management protocols for effective care of older persons. This review describes our experience during this period attending to the healthcare needs of both the acutely ill and clinically stable patients at the first purpose-built facility for the care of older persons in Nigeria, the Chief Tony Anenih Geriatric Centre (CTAGC), University College Hospital, Ibadan. A major strategy recommended by the World Health Organization was a lockdown with restricted movements and laid down rules for engagement. As such, the CTAGC also embarked on steps to ensure patient safety as well as effective care. Prior to the lockdown, targeted activities included fumigation of the centre as well as health education and promotional activities. Measures were put in place to care for up to 95% of our patients at home. Thus, a "Care in Place" approach was adopted to enable them to take ownership of their care. Ambulatory older patients were seen on an out-patient basis following scheduled appointments after a telephone consultation through the hospital's designated lines. Clients were managed for their routine health conditions which were mostly non-communicable diseases (NCDs). Also, acutely ill older patients were admitted for acute exacerbation and/or complications of their chronic morbidities. Importantly, 60% of admitted patients presented with COVID like symptoms but they all tested negative for COVID 19. Based on our experience at the CTAGC, older persons can be successfully managed through a "Care in place" approach in a resource-poor setting during pandemics with high infectivity rates such as COVID 19. The information hereby generated is beneficial for future practice.

Metformin and SARS-CoV-2: mechanistic lessons on air pollution to weather the cytokine/thrombotic storm in COVID-19

Pathological signaling in the lung induced by particulate matter (PM) air pollution partially overlaps with that provoked by COVID-19, the pandemic disease caused by infection with the novel coronavirus SARS-CoV-2. Metformin is capable of suppressing one of the molecular triggers of the proinflammatory and prothrombotic processes of urban PM air pollution, namely the mitochondrial ROS/Ca2+ release-activated Ca2+ channels (CRAC)/IL-6 cascade. Given the linkage between mitochondrial functionality, ion channels, and inflamm-aging, the ability of metformin to target mitochondrial electron transport and prevent ROS/CRAC-mediated IL-6 release might illuminate new therapeutic avenues to quell the raging of the cytokine and thrombotic-like storms that are the leading causes of COVID-19 morbidity and mortality in older people. The incorporation of infection rates, severity and lethality of SARS-CoV-2 infections as new outcomes of metformin usage in elderly populations at risk of developing severe COVID-19, together with the assessment of bronchial/serological titers of inflammatory cytokines and D-dimers, could provide a novel mechanistic basis for the consideration of metformin as a therapeutic strategy against the inflammatory and thrombotic states underlying the gerolavic traits of SARS-CoV-2 infection.

Airway Remodeling in Asthma

Asthma is an inflammatory disease of the airways that may result from exposure to allergens or other environmental irritants, resulting in bronchoconstriction, wheezing, and shortness of breath. The structural changes of the airways associated with asthma, broadly referred to as airway remodeling, is a pathological feature of chronic asthma that contributes to the clinical manifestations of the disease. Airway remodeling in asthma constitutes cellular and extracellular matrix changes in the large and small airways, epithelial cell apoptosis, airway smooth muscle cell proliferation, and fibroblast activation. These pathological changes in the airway are orchestrated by crosstalk of different cell types within the airway wall and submucosa. Environmental exposures to dust, chemicals, and cigarette smoke can initiate the cascade of pro-inflammatory responses that trigger airway remodeling through paracrine signaling and mechanostimulatory cues that drive airway remodeling. In this review, we explore three integrated and dynamic processes in airway remodeling: (1) initiation by epithelial cells; (2) amplification by immune cells; and (3) mesenchymal effector functions. Furthermore, we explore the role of inflammaging in the dysregulated and persistent inflammatory response that perpetuates airway remodeling in elderly asthmatics.

Coronavirus Disease 2019 (COVID-19) in Children - What We Know So Far and What We Do Not

Pediatric coronavirus disease-19 (COVID-19) infection is relatively mild when compared to adults, and children are reported to have a better prognosis. Mortality in children appears rare. Clinical features of COVID-19 in children include fever and cough, but a large proportion of infected children appears to be asymptomatic and may contribute to transmission. It remains unclear why children and young adults are less severely affected than older individuals, but this might involve differences in immune system function in the elderly and/or differences in the expression/function of the cellular receptor for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)- Angiotensin converting enzyme 2 (ACE2). Laboratory findings and chest imaging may not be specific in children with COVID-19. Diagnosis is by Reverse transcriptase-Polymerase chain reaction (RT-PCR) testing of upper or lower respiratory tract secretions. This review additionally considers COVID-19 in immunosuppressed children, and also suggests a management algorithm for the few children who appear to present with life threatening infection, including the potential use of antiviral and immunomodulatory treatment. The most significant threat to global child health from SARS-CoV-2 is unlikely to be related to COVID 19 in children, but rather the socio-economic consequences of a prolonged pandemic.

Coronavirus Disease 2019 (COVID-19) in Children - What We Know So Far and What We Do Not

Pediatric coronavirus disease-19 (COVID-19) infection is relatively mild when compared to adults, and children are reported to have a better prognosis. Mortality in children appears rare. Clinical features of COVID-19 in children include fever and cough, but a large proportion of infected children appears to be asymptomatic and may contribute to transmission. It remains unclear why children and young adults are less severely affected than older individuals, but this might involve differences in immune system function in the elderly and/or differences in the expression/function of the cellular receptor for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)- Angiotensin converting enzyme 2 (ACE2). Laboratory findings and chest imaging may not be specific in children with COVID-19. Diagnosis is by Reverse transcriptase-Polymerase chain reaction (RT-PCR) testing of upper or lower respiratory tract secretions. This review additionally considers COVID-19 in immunosuppressed children, and also suggests a management algorithm for the few children who appear to present with life threatening infection, including the potential use of antiviral and immunomodulatory treatment. The most significant threat to global child health from SARS-CoV-2 is unlikely to be related to COVID 19 in children, but rather the socio-economic consequences of a prolonged pandemic.

Aging Fits the Disease Criteria of the International Classification of Diseases

The disease criteria used by the World Health Organization (WHO) were applied to human biological aging in order to assess whether aging can be classified as a disease. These criteria were developed for the 11th revision of the International Classification of Diseases (ICD) and included disease diagnostics, mechanisms, course and outcomes, known interventions, and linkage to genetic and environmental factors. RESULTS: Biological aging can be diagnosed with frailty indices, functional, blood-based biomarkers. A number of major causal mechanisms of human aging involved in various organs have been described, such as inflammation, replicative cellular senescence, immune senescence, proteostasis failures, mitochondrial dysfunctions, fibrotic propensity, hormonal aging, body composition changes, etc. We identified a number of clinically proven interventions, as well as genetic and environmental factors of aging. Therefore, aging fits the ICD-11 criteria and can be considered a disease. Our proposal was submitted to the ICD-11 Joint Task force, and this led to the inclusion of the extension code for "Ageing-related" (XT9T) into the "Causality" section of the ICD-11. This might lead to greater focus on biological aging in global health policy and might provide for more opportunities for the new therapy developers.

IL10 deficiency promotes alveolar enlargement and lymphoid dysmorphogenesis in the aged murine lung

The connection between aging-related immune dysfunction and the lung manifestations of aging is poorly understood. A detailed characterization of the aging IL10-deficient murine lung, a model of accelerated aging and frailty, reconciles features of both immunosenescence and lung aging in a coherent model. Airspace enlargement developed in the middle-aged (12 months old) and aged (20-22 months old) IL10-deficient lung punctuated by an expansion of macrophages and alveolar cell apoptosis. Compared to wild-type (WT) controls, the IL10-deficient lungs from young (4-month-old) mice showed increased oxidative stress which was enhanced in both genotypes by aging. Active caspase 3 staining was increased in the alveolar epithelial cells of aged WT and mutant lungs but was greater in the IL10-deficient milieu. Lung macrophages were increased in the aged IL10-deficient lungs with exuberant expression of MMP12. IL10 treatment of naïve and M2-polarized bone marrow-derived WT macrophages reduced MMP12 expression. Conditioned media studies demonstrated the secretome of aged mutant macrophages harbors reduced AECII prosurvival factors, specifically keratinocyte growth factor (KGF) and hepatocyte growth factor (HGF), promotes cell death, and reduces survival of primary alveolar epithelial cells. Compared to WT controls, aged IL10-deficient mice have increased parenchymal lymphoid collections comprised of a reduced number of apoptotic cells and B cells. We establish that IL10 is a key modulator of airspace homeostasis and lymphoid morphogenesis in the aging lung enabling macrophage-mediated alveolar epithelial cell survival and B-cell survival within tertiary lymphoid structures.

Increased Chitotriosidase Is Associated With Aspergillus and Frequent Exacerbations in South-East Asian Patients With Bronchiectasis

BACKGROUND

Chitinase activity is an important innate immune defence mechanism against infection that includes fungi. The 2 human chitinases: chitotriosidase (CHIT1) and acidic mammalian chitinase are associated to allergy, asthma, and COPD; however, their role in bronchiectasis and bronchiectasis-COPD overlap (BCO) is unknown.

RESEARCH QUESTION

What is the association between chitinase activity, airway fungi and clinical outcomes in bronchiectasis and bronchiectasis-COPD overlap?

STUDY DESIGN AND METHODS

A prospective cohort of 463 individuals were recruited across five hospital sites in three countries (Singapore, Malaysia, and Scotland) including individuals who were not diseased (n = 35) and who had severe asthma (n = 54), COPD (n = 90), bronchiectasis (n = 241) and BCO (n = 43). Systemic chitinase levels were assessed for bronchiectasis and BCO and related to clinical outcomes, airway Aspergillus status, and underlying pulmonary mycobiome profiles.

RESULTS

Systemic chitinase activity is elevated significantly in bronchiectasis and BCO and exceed the activity in other airway diseases. CHIT1 activity strongly predicts bronchiectasis exacerbations and is associated with the presence of at least one Aspergillus species in the airway and frequent exacerbations (≥3 exacerbations/y). Subgroup analysis reveals an association between CHIT1 activity and the "frequent exacerbator" phenotype in South-East Asian patients whose airway mycobiome profiles indicate the presence of novel fungal taxa that include Macroventuria, Curvularia and Sarocladium. These taxa, enriched in frequently exacerbating South-East Asian patients with high CHIT1 may have potential roles in bronchiectasis exacerbations.

INTERPRETATION

Systemic CHIT1 activity may represent a useful clinical tool for the identification of fungal-driven "frequent exacerbators" with bronchiectasis in South-East Asian populations.

Community-acquired pneumonia in critically ill very old patients: a growing problem

Very old (aged ≥80 years) adults constitute an increasing proportion of the global population. Currently, this subgroup of patients represents an important percentage of patients admitted to the intensive care unit. Community-acquired pneumonia (CAP) frequently affects very old adults. However, there are no specific recommendations for the management of critically ill very old CAP patients. Multiple morbidities, polypharmacy, immunosenescence and frailty contribute to an increased risk of pneumonia in this population. CAP in critically ill very old patients is associated with higher short- and long-term mortality; however, because of its uncommon presentation, diagnosis can be very difficult. Management of critically ill very old CAP patients should be guided by their baseline characteristics, clinical presentation and risk factors for multidrug-resistant pathogens. Hospitalisation in intermediate care may be a good option for critical ill very old CAP patients who do not require invasive procedures and for whom intensive care is questionable in terms of benefit.

There is currently no international recommendation for the management of critically ill older patients over 80 years of age with CAP. We report and discuss recent literature in order to help physicians in the decision-making process of these patients.http://bit.ly/2ql0mIz

The Infections Causing Acute Respiratory Failure in Elderly Patients

The immune system of older individuals declines with advancing age (“immunosenescence”) increasing susceptibility to infection, as well as to an increased risk of a worse outcome. Severe community-acquired pneumonia and acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are causes of acute respiratory failure (ARF) in elderly patients. Non-invasive mechanical ventilation (NIV) is effective in the treatment of patients with ARF, above all in case of AECOPD.

Airway microbiome composition correlates with lung function and arterial stiffness in an age-dependent manner

Objective

To investigate age-associated changes in airway microbiome composition and their relationships with lung function and arterial stiffness among genetically matched young and elderly pairs.

Methods

Twenty-four genetically linked family pairs comprised of younger (≤40 years) and older (≥60 years) healthy participants were recruited (Total n = 48). Lung function and arterial stiffness (carotid-femoral pulse wave velocity (PWV) and augmentation index (AIx)) were assessed. Sputum samples were collected for targeted 16S rRNA gene amplicon sequencing and correlations between microbiome composition, lung function and arterial stiffness were investigated.

Results

Elderly participants exhibited reductions in lung function (FEV1 (p<0.001), FVC (p<0.001) and percentage FEV1/FVC (p = 0.003)) and a 1.3–3.9-fold increase in arterial stiffness (p<0.001) relative to genetically related younger adults. Elderly adults had a higher relative abundance of Firmicutes (p = 0.035) and lower relative abundance of Proteobacteria (p = 0.014), including specific genera Haemophilus (p = 0.024) and Lautropia (p = 0.020) which were enriched in the younger adults. Alpha diversity was comparable between young and elderly pairs (p>0.05) but was inversely associated with lung function (FEV1%Predicted and FVC %Predicted) in the young (p = 0.006 and p = 0.003) though not the elderly (p = 0.481 and p = 0.696). Conversely, alpha diversity was negatively associated with PWV in the elderly (p = 0.01) but not the young (p = 0.569). Specifically, phylum Firmicutes including the genus Gemella were correlated with lung function (FVC %Predicted) in the young group (p = 0.047 and p = 0.040), while Fusobacteria and Leptotrichia were associated with arterial stiffness (PWV) in the elderly (both p = 0.004).

Conclusion

Ageing is associated with increased Firmicutes and decreased Proteobacteria representation in the airway microbiome among a healthy Asian cohort. The diversity and composition of the airway microbiome is independently associated with lung function and arterial stiffness in the young and elderly groups respectively. This suggests differential microbial associations with these phenotypes at specific stages of life with potential prognostic implications.

Advanced age adversely affects chronic rhinosinusitis surgical outcomes

BACKGROUND

Patient-specific and disease-specific factors shape the course of chronic rhinosinusitis (CRS) and its response to treatment, with optimal management involving interventions tailored to these factors. Recent evidence suggests CRS inflammatory signatures depend on age. The objective of this study was to determine whether age also influences quality-of-life (QOL) and postoperative outcomes.

METHODS

Retrospective analysis of prospectively collected QOL data from 403 adults with medically refractory CRS who underwent functional endoscopic sinus surgery (FESS) at a tertiary care medical center between 2014 and 2018 was undertaken. Total and subdomain scores from the 22-item Sino-Nasal Outcome Test (SNOT-22) and the Short Form 8 Health Survey (SF-8) measure of general health completed at preoperative and postoperative visits were reviewed.

RESULTS

Patients were divided into young (18 to 39 years, n = 100), middle-aged (40 to 59 years, n = 172), and elderly (≥60 years, n = 131) groups. Baseline total SNOT-22 scores differed between groups (p = 0.01), with middle-aged patients having the highest symptom burden and elderly patients having the lowest. Similar patterns were observed for SNOT-22 subdomains. Elderly patients reported smaller improvements and were less likely to achieve a minimally important clinical difference. CRS patients had worse SF-8 scores compared to the general population, and elderly patients were the least likely to match population norms following surgery. Age was an independent predictor of QOL outcomes after FESS.

CONCLUSION

Age may play a significant role in CRS pathophysiology, symptom burden, and surgical outcomes. Elderly patients report smaller improvements in disease-specific and general health QOL after surgery. CRS management in the elderly population should incorporate age-dependent differences in symptom burden and expectations into treatment algorithms.