Inhibition of Dopamine Neurons Prevents Incentive Value Encoding of a Reward Cue: With Revelations from Deep Phenotyping.

The survival of an organism is dependent on its ability to respond to cues in the environment. Such cues can attain control over behavior as a function of the value ascribed to them. Some individuals have an inherent tendency to attribute reward-paired cues with incentive motivational value, or incentive salience. For these individuals, termed sign-trackers, a discrete cue that precedes reward delivery becomes attractive and desirable in its own right. Prior work suggests that the behavior of sign-trackers is dopamine-dependent, and cue-elicited dopamine in the NAc is believed to encode the incentive value of reward cues. Here we exploited the temporal resolution of optogenetics to determine whether selective inhibition of ventral tegmental area (VTA) dopamine neurons during cue presentation attenuates the propensity to sign-track. Using male tyrosine hydroxylase (TH)-Cre Long Evans rats, it was found that, under baseline conditions, ∼84% of TH-Cre rats tend to sign-track. Laser-induced inhibition of VTA dopamine neurons during cue presentation prevented the development of sign-tracking behavior, without affecting goal-tracking behavior. When laser inhibition was terminated, these same rats developed a sign-tracking response. Video analysis using DeepLabCutTM revealed that, relative to rats that received laser inhibition, rats in the control group spent more time near the location of the reward cue even when it was not present and were more likely to orient toward and approach the cue during its presentation. These findings demonstrate that cue-elicited dopamine release is critical for the attribution of incentive salience to reward cues.SIGNIFICANCE STATEMENT Activity of dopamine neurons in the ventral tegmental area (VTA) during cue presentation is necessary for the development of a sign-tracking, but not a goal-tracking, conditioned response in a Pavlovian task. We capitalized on the temporal precision of optogenetics to pair cue presentation with inhibition of VTA dopamine neurons. A detailed behavioral analysis with DeepLabCutTM revealed that cue-directed behaviors do not emerge without dopamine neuron activity in the VTA. Importantly, however, when optogenetic inhibition is lifted, cue-directed behaviors increase, and a sign-tracking response develops. These findings confirm the necessity of dopamine neuron activity in the VTA during cue presentation to encode the incentive value of reward cues.

Pulmonary thrombosis associated with COVID-19 pneumonia: Beyond classical pulmonary thromboembolism.

BACKGROUND: Classical pulmonary thromboembolism (TE) and local pulmonary thrombosis (PT) have been suggested as mechanisms of thrombosis in COVID-19. However, robust evidence is still lacking because this was mainly based on retrospective studies, in which patients were included when TE was suspected. METHODS: All patients with COVID-19 pneumonia underwent computed tomography and pulmonary angiography in a prospective study. The main objective was to determine the number and percentage of thrombi surrounded by lung opacification (TSO) in each patient, as well as their relationship with percentage of lung involvement (TLI), to distinguish classical TE (with a random location of thrombi that should correspond to a percentage of TSO equivalent to the TLI) from PT. We determined TLI by artificial intelligence. Analyses at patient level (TLI and percentage of TSO) and at thrombi level (TLI and TSO) were performed. RESULTS: We diagnosed TE in 70 out of 184 patients. Three (2-8) thrombi/patient were detected. The percentage of TSO was 100% (75-100) per patient, and TLI was 19.9% (4.6-35.2). Sixty-five patients (92.9%) were above the random scenario with higher percentage of TSO than TLI. Most thrombi were TSO (n = 299, 75.1%). When evaluating by TLI (<10%, 10%-20%, 20%-30% and >30%), percentage of TSO was higher in most groups. Thrombi were mainly in subsegmental/segmental arteries, and percentage of TSO was higher in all locations. CONCLUSIONS: Thrombi in COVID-19 were found within lung opacities in a higher percentage than lung involvement, regardless of TLI and clot location, supporting the hypothesis of local PT rather than "classic TE".

Cardiopulmonary Complications after Pulmonary Embolism in COVID-19.

Although pulmonary embolism (PE) is a frequent complication in COVID-19, its consequences remain unknown. We performed pulmonary function tests, echocardiography and computed tomography pulmonary angiography and identified blood biomarkers in a cohort of consecutive hospitalized COVID-19 patients with pneumonia to describe and compare medium-term outcomes according to the presence of PE, as well as to explore their potential predictors. A total of 141 patients (56 with PE) were followed up during a median of 6 months. Post-COVID-19 radiological lung abnormalities (PCRLA) and impaired diffusing capacity for carbon monoxide (DLCOc) were found in 55.2% and 67.6% cases, respectively. A total of 7.3% had PE, and 6.7% presented an intermediate-high probability of pulmonary hypertension. No significant difference was found between PE and non-PE patients. Univariate analysis showed that age > 65, some clinical severity factors, surfactant protein-D, baseline C-reactive protein, and both peak red cell distribution width and Interleukin (IL)-10 were associated with DLCOc < 80%. A score for PCRLA prediction including age > 65, minimum lymphocyte count, and IL-1ß concentration on admission was constructed with excellent overall performance. In conclusion, reduced DLCOc and PCRLA were common in COVID-19 patients after hospital discharge, but PE did not increase the risk. A PCRLA predictive score was developed, which needs further validation.

Elevated complement C3 and increased CD8 and type 1 helper lymphocyte T populations in patients with post-COVID-19 condition.

BACKGROUND: Biological markers associated to post-COVID-19 condition (PCC) have not been clearly identified. METHODS: Eighty-two patients attending our post-COVID-19 outpatient clinic were recruited and classified as fully recovered (40.2%) or presenting with PCC (59.8%). Clinical and radiological data, laboratory markers, cytokines, and lymphocyte populations were analyzed. RESULTS: Median number of days after hospitalization was 78.5 [p25-p75: 60-93] days. PCC was significantly more frequent in women, in patients with a previously critical COVID-19, and in those with two or more comorbidities. No differences were found in lymphocyte counts, ferritin, C-reactive protein, D-dimer or sCD25, IL-1ß, IL-1Ra, IL-6, CXCL8, IL-17A, IL-18, IL-22, IFN-γ, TNF-α, and IL-10 cytokines levels. PCC patients showed significantly higher levels of complement factor C3 than fully recovered patients: median C3 128 mg/dL [p25-p75:107-135] vs 111 mg/dL [p25-p75: 100-125] (p =.005), respectively. In the flow cytometry assessment of peripheral blood lymphocyte subpopulations, PCC patients showed significantly increased CD8 populations compared to fully recovered patients: median CD8: 529 [p25-p75: 384-683] vs 370/mm3 [p25-p75:280-523], p =.007. When type 1, 2, 17/22, and 17.1 helper and follicular T lymphocyte subpopulations were analyzed, the frequency of Th1 was significantly higher in PCC patients compared to fully recovered patients (30% vs 38.5%, p =.028). CONCLUSION: Patients with a post-COVID-19 condition showed significantly increased immunological parameters of inflammation (complement factor C3 and CD8 and Th1 T lymphocyte populations) compared to fully recovered patients. These parameters could be used as biological markers of this condition.

Facemask analyses for the non-invasive detection of chronic and acute P. aeruginosa lung infections using nanoparticle-based immunoassays.

Pseudomonas aeruginosa (P. aeruginosa) is a pathogen that persistently colonizes the respiratory tract of patients with chronic lung diseases. The risk of acquiring a chronic P. aeruginosa infection can be minimized by rapidly detecting the pathogen in the patient's airways and promptly administrating adequate antibiotics. However, the rapid detection of P. aeruginosa in the lungs involves the analysis of sputum, which is a highly complex matrix that is not always available. Here, we propose an alternative diagnosis based on analyzing breath aerosols. In this approach, nanoparticle immunosensors identify bacteria adhered to the polypropylene layer of a surgical facemask that was previously worn by the patient. A polypropylene processing protocol was optimized to ensure the efficient capture and analysis of the target pathogen. The proposed analytical platform has a theoretical limit of detection of 105 CFU mL-1 in aerosolized mock samples, and a dynamic range between 105 and 108 CFU mL-1. When tested with facemasks worn by patients, the biosensors were able to detect chronic and acute P. aeruginosa lung infections, and to differentiate them from respiratory infections caused by other pathogens. The results shown here pave the way to diagnose Pseudomonas infections at the bedside, as well as to identify the progress from chronic to acute infection.

The Role of IL-33/ST2 in COPD and Its Future as an Antibody Therapy.

COPD is a leading cause of mortality and morbidity worldwide and is associated with a high socioeconomic burden. Current treatment includes the use of inhaled corticosteroids and bronchodilators, which can help to improve symptoms and reduce exacerbations; however, there is no solution for restoring lung function and the emphysema caused by loss of the alveolar tissue. Moreover, exacerbations accelerate progression and challenge even more the management of COPD. Mechanisms of inflammation in COPD have been investigated over the past years, thus opening new avenues to develop novel targeted-directed therapies. Special attention has been paid to IL-33 and its receptor ST2, as they have been found to mediate immune responses and alveolar damage, and their expression is upregulated in COPD patients, which correlates with disease progression. Here we summarize the current knowledge on the IL-33/ST2 pathway and its involvement in COPD, with a special focus on developed antibodies and the ongoing clinical trials using anti-IL-33 and anti-ST2 strategies in COPD patients.

Mesenchymal Stem Cells from COPD Patients Are Capable of Restoring Elastase-Induced Emphysema in a Murine Experimental Model.

COPD is a chronic lung disease that affects millions of people, declining their lung function and impairing their life quality. Despite years of research and drug approvals, we are still not capable of halting progression or restoring normal lung function. Mesenchymal stem cells (MSC) are cells with extraordinary repair capacity, and MSC-based therapy brings future hope for COPD treatment, although the best source and route of administration are unclear. MSC from adipose tissue (AD-MSC) represents an option for autologous treatment; however, they could be less effective than donor MSC. We compared in vitro behavior of AD-MSC from COPD and non-COPD individuals by migration/proliferation assay, and tested their therapeutic potential in an elastase mouse model. In addition, we tested intravenous versus intratracheal routes, inoculating umbilical cord (UC) MSC and analyzed molecular changes by protein array. Although COPD AD-MSC have impaired migratory response to VEGF and cigarette smoke, they were as efficient as non-COPD in reducing elastase-induced lung emphysema. UC-MSC reduced lung emphysema regardless of the administration route and modified the inflammatory profile in elastase-treated mice. Our data demonstrate equal therapeutic potential of AD-MSC from COPD and non-COPD subjects in the pre-clinical model, thus supporting their autologous use in disease.

Systemic inflammation and sympathetic activation in gestational diabetes mellitus with obstructive sleep apnea.

BACKGROUND: Although some evidence suggests an association between obstructive sleep apnea (OSA) and gestational diabetes mellitus (GDM), its consequences still remain largely unknown. We sought to determine whether OSA is associated with higher inflammation and sympathetic levels in GDM, and to relate them with insulin resistance and perinatal outcomes. METHODS: OSA was identified by polysomnography and defined as an apnea-hypopnea index of ≥ 5 h-1. Plasma cytokines (TNF-α, IL-1ß, IL-6, IL-8, IL-10), metanephrine, and normetanephrine were determined by immunoassays. RESULTS: We included 17 patients with GDM and OSA and 34 without OSA. Women with GDM and OSA had higher normetanephrine concentrations [81 IQR (59-134) vs. 68 (51-81) pg/mL]. No differences in the inflammatory profile were found, while IL-1ß was higher in patients with mean nocturnal oxyhemoglobin saturation ≤ 94%. We found positive correlations between increased sympathetic activation and IL-1ß, with obstructive apneas, while time in REM showed an inverse relationship with IL-1ß and metanephrine. Furthermore, IL-10 was inversely related with time in sleep stages 1-2, and with the arousal index, and it was positively related with time in slow-wave sleep. Significant correlations were also found between IL-1ß and insulin resistance. There were no significant differences in neonatal characteristics; however, we found inverse relationships between IL-10 and birth weight (BW), and percentile of BW. CONCLUSIONS: OSA increased sympathetic activity, and IL-1ß concentration was higher in patients with GDM with lower nocturnal oxygenation, all of which were related with obstructive events, and time in REM. Moreover, IL-1ß was related with insulin resistance, and IL-10 inversely correlated with neonatal BW.

TLR/WNT: A Novel Relationship in Immunomodulation of Lung Cancer.

The most frequent cause of death by cancer worldwide is lung cancer, and the 5-year survival rate is still very poor for patients with advanced stage. Understanding the crosstalk between the signaling pathways that are involved in disease, especially in metastasis, is crucial to developing new targeted therapies. Toll-like receptors (TLRs) are master regulators of the immune responses, and their dysregulation in lung cancer is linked to immune escape and promotes tumor malignancy by facilitating angiogenesis and proliferation. On the other hand, over-activation of the WNT signaling pathway has been reported in lung cancer and is also associated with tumor metastasis via induction of Epithelial-to-mesenchymal-transition (EMT)-like processes. An interaction between both TLRs and the WNT pathway was discovered recently as it was found that the TLR pathway can be activated by WNT ligands in the tumor microenvironment; however, the implications of such interactions in the context of lung cancer have not been discussed yet. Here, we offer an overview of the interaction of TLR-WNT in the lung and its potential implications and role in the oncogenic process.

Effects of Inhaled Corticosteroids on the Innate Immunological Response to Pseudomonas aeruginosa Infection in Patients with COPD.

Inhaled corticosteroids (ICS) use is associated with an increased risk of Pseudomonas aeruginosa (PA) infection in patients with COPD. We aimed to evaluate the effects of ICS on alveolar macrophages in response to PA in COPD patients with and without baseline ICS treatment (COPD and COPD + ICS, respectively) as well as smoker and nonsmoker controls. To do so, cells were infected with PA and cotreated with budesonide (BUD) or fluticasone propionate (FLU). The analysis of NF-κB and c-jun activity revealed a significant increase in both factors in response to PA cotreated with BUD/FLU in smokers but not in COPD or COPD + ICS patients when compared with PA infection alone. The expression of Toll-like receptor 2 (TLR2) and the transcription factor c-jun were induced upon PA infection in nonsmokers only. Moreover, in the smoker and COPD groups, there was a significant increase in TLR2 and a decrease in c-jun expression when treated with BUD/FLU after PA infection, which were not observed in COPD + ICS patients. Therefore, the chronic use of ICS seemingly makes the macrophages tolerant to BUD/FLU stimulation compared with those from patients not treated with ICS, promoting an impaired recognition of PA and activity of alveolar macrophages in terms of altered expression of TLR2 and cytokine production, which could explain the increased risk of PA infection in COPD patients under ICS treatment.

Predictive Immunological, Virological, and Routine Laboratory Markers for Critical COVID-19 on Admission.

BACKGROUND: Early identification of COVID-19 patients at risk of critical illness is a challenging endeavor for clinicians. We aimed to establish immunological, virological, and routine laboratory markers, which, in combination with clinical information, may allow identifying such patients. METHODS: Blood tests to measure neutrophil/lymphocyte ratio (NLR) and levels of ferritin, CRP, D-dimer, complement components (C3 and C4), cytokines, and lymphocyte subsets, as well as SARS-Cov-2 RT-PCR tests, were performed in COVID-19-confirmed cases within 48 hours of admission. RT-PCR cycle threshold (Ct) values from oropharyngeal or nasopharyngeal swabs were determined on the day of admission. Symptom severity was categorized as mild (grade 1), severe (grade 2), or critical (grade 3). RESULTS: Of 120 patients who were included, 49 had mild, 32 severe, and 39 critical COVID-19. Levels of ferritin >370 ng/mL (OR 16.4, 95% CI 5.3-50.8), D-dimer >440 ng/mL (OR 5.45, 95% CI 2.36-12.61), CRP >7.65 mg/dL (OR 11.54, 95% CI 4.3-30.8), NLR >3.77 (OR 13.4, 95% CI 4.3-41.1), IL-6 >142.5 pg/mL (OR 8.76, 95% CI 3.56-21.54), IL-10 >10.8 pg/mL (OR 16.45, 95% CI 5.32-50.81), sIL-2rα (sCD25) >804.5 pg/mL (OR 14.06, 95% CI 4.56-43.28), IL-1Ra >88.4 pg/mL (OR 4.54, 95% CI 2.03-10.17), and IL-18 >144 pg/mL (OR 17.85, 95% CI 6.54-48.78) were associated with critical COVID-19 in the univariate age-adjusted analysis. This association was confirmed in the multivariate age-adjusted analysis only for ferritin, CRP, NLR, IL-10, sIL-2rα, and IL-18. T, B, and NK cells were significantly decreased in critical patients. SARS-CoV-2 was not detected in blood except in 3 patients who had indeterminate results. RT-PCR Ct values from oropharyngeal or nasopharyngeal swabs on admission were not related to symptom severity. CONCLUSION: Ferritin, D-dimer, CRP, NLR, cytokine (IL-18 and IL-10), and cytokine receptor (IL-6, IL1-Ra, and sCD25) test results combined with clinical data can contribute to the early identification of critical COVID-19 patients.

Bone marrow characterization in COPD: a multi-level network analysis.

BACKGROUND: Bone marrow (BM) produces hematopoietic and progenitor cells that contribute to distant organ inflammation and repair. Chronic obstructive pulmonary disease (COPD) is characterized by defective lung repair. Yet, BM composition has not been previously characterized in COPD patients. METHODS: In this prospective and controlled study, BM was obtained by sternum fine-needle aspiration in 35 COPD patients and 25 healthy controls (10 smokers and 15 never-smokers). BM cell count and immunophenotype were determined by microscopy and flow cytometry, respectively. Circulating inflammatory (C-reactive protein, IL-6, IL-8) and repair markers (HGF, IGF, TGF-ß, VEGF) were quantified by ELISA. Results were integrated by multi-level network correlation analysis. RESULTS: We found that: (1) there were no major significant pair wise differences between COPD patients and controls in the BM structural characteristics; (2) multi-level network analysis including patients and controls identifies a relation between immunity, repair and lung function not previously described, that remains in the COPD network but is absent in controls; and (3) this novel network identifies eosinophils as a potential mediator relating immunity and repair, particularly in patients with emphysema. CONCLUSIONS: Overall, these results suggest that BM is activated in COPD with impaired repair capacity in patients with more emphysema and/or higher circulating eosinophils.

B Cell-Activating Factor. An Orchestrator of Lymphoid Follicles in Severe Chronic Obstructive Pulmonary Disease.

RATIONALE: Patients with chronic obstructive pulmonary disease (COPD) have increased pulmonary lymphoid follicle (LF) counts. B cell-activating factor of tumor necrosis factor family (BAFF) regulates B cells in health, but its role in COPD pathogenesis is unclear. OBJECTIVES: To determine whether BAFF expression in pulmonary LFs correlates with COPD severity, LF size or number, and/or readouts of B-cell function in LFs. METHODS: We correlated BAFF immunostaining in LFs in lung explants or biopsies from nonsmoking control subjects (NSC), smokers without COPD (SC), and patients with COPD with the number and size of LFs, and LF B-cell apoptosis, activation, and proliferation. We analyzed serum BAFF levels and BAFF expression in B cells in blood and bronchoalveolar lavage samples from the same subject groups. We assessed whether: (1) cigarette smoke extract (CSE) increases B-cell BAFF expression and (2) recombinant BAFF (rBAFF) rescues B cells from CSE-induced apoptosis by inhibiting activation of nuclear factor-κB (NF-κB). MEASUREMENTS AND MAIN RESULTS: Patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage IV COPD had increased numbers and larger pulmonary LFs than patients with GOLD stages I-II COPD and SC. We identified two main types of pulmonary LFs: (1) type A, the predominant type in GOLD stages I-II COPD and SC, characterized by abundant apoptotic but few BAFF-positive cells (mostly B cells); and (2) type B, the main type in GOLD stage IV COPD, characterized by abundant BAFF-positive cells but few apoptotic cells (mostly B cells). BAFF levels were also higher in blood and bronchoalveolar lavage B cells in patients with COPD versus NSC and SC. Surprisingly, rBAFF blocked CSE-induced B-cell apoptosis by inhibiting CSE-induced NF-κB activation. CONCLUSIONS: Our data support the hypothesis that B-cell BAFF expression creates a self-perpetuating loop contributing to COPD progression by promoting pulmonary B-cell survival and LF expansion.

Haemophilus influenzae induces steroid-resistant inflammatory responses in COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an inflammatory disorder partially resistant to glucocorticoids. A reduced histone deacetylase (HDAC) activity has been proposed to explain this resistance. Haemophilus influenzae frequently colonizes the airways of COPD patients, where it enhances inflammation. The effects of Haemophilus influenzae on HDAC activity have not been investigated before. METHODS: The effects of the presence or absence of Haemophilus influenzae ex-vivo and in vitro were studied. To this end, we determined: (1) cytokine release in alveolar macrophages (AM) from 7 patients with COPD, 5 healthy smokers, 6 healthy non-smokers and (2) HDAC activity, nuclear factor kappa B (NF-κB) activation in a macrophage-like cell line (PMA-transformed U937 cells) co-cultured with epithelial cells. Experiments were repeated with dexamethasone (1 µM) and/or the HDAC enhancer theophylline (10 µM). RESULTS: Haemophilus influenzae induced a steroid-resistant inflammatory response in AM from COPD and controls and decreased HDAC activity, activated NF-κB and induced the secretion of several cytokines (IL-6, IL-8, IL-1ß, IL-10 and TNF-α) (p < 0.001 for all comparisons) in the macrophage-like cell line. Dexamethasone reduced NF-κB activation but it did not modify HDAC activity. The addition of theophylline to dexamethasone increased HDAC activity and suppressed cytokine release completely, without modifying NF-κB activation. CONCLUSIONS: These results indicate that Haemophilus influenzae reduces HDAC activity and induces a NF-κB mediated inflammatory response that is only partially suppressed by glucocorticoids irrespective of having COPD. Yet, the latter can be fully restored by targeting HDAC activity.

Role of PATJ in stroke prognosis by modulating endothelial to mesenchymal transition through the Hippo/Notch/PI3K axis.

Through GWAS studies we identified PATJ associated with functional outcome after ischemic stroke (IS). The aim of this study was to determine PATJ role in brain endothelial cells (ECs) in the context of stroke outcome. PATJ expression analyses in patient's blood revealed that: (i) the risk allele of rs76221407 induces higher expression of PATJ, (ii) PATJ is downregulated 24 h after IS, and (iii) its expression is significantly lower in those patients with functional independence, measured at 3 months with the modified Rankin scale ((mRS) ≤2), compared to those patients with marked disability (mRS = 4-5). In mice brains, PATJ was also downregulated in the injured hemisphere at 48 h after ischemia. Oxygen-glucose deprivation and hypoxia-dependent of Hypoxia Inducible Factor-1α also caused PATJ depletion in ECs. To study the effects of PATJ downregulation, we generated PATJ-knockdown human microvascular ECs. Their transcriptomic profile evidenced a complex cell reprogramming involving Notch, TGF-ß, PI3K/Akt, and Hippo signaling that translates in morphological and functional changes compatible with endothelial to mesenchymal transition (EndMT). PATJ depletion caused loss of cell-cell adhesion, upregulation of metalloproteases, actin cytoskeleton remodeling, cytoplasmic accumulation of the signal transducer C-terminal transmembrane Mucin 1 (MUC1-C) and downregulation of Notch and Hippo signaling. The EndMT phenotype of PATJ-depleted cells was associated with the nuclear recruitment of MUC1-C, YAP/TAZ, ß-catenin, and ZEB1. Our results suggest that PATJ downregulation 24 h after IS promotes EndMT, an initial step prior to secondary activation of a pro-angiogenic program. This effect is associated with functional independence suggesting that activation of EndMT shortly after stroke onset is beneficial for stroke recovery.

Redefining the Role of Bronchoscopy in the Workup of Severe Uncontrolled Asthma in the Era of Biologics: A Prospective Study.

BACKGROUND: Severe uncontrolled asthma (SUA) is frequently treated with biologic therapy if a T2 phenotype is found. Bronchoscopy is not routinely recommended in these patients unless a specific indication to rule out comorbidities is present. RESEARCH QUESTION: Is routine bronchoscopy safe and useful in phenotyping and endotyping patients with SUA before the indication of a biologic therapy? STUDY DESIGN AND METHODS: Prospective study of consecutive patients with SUA who were referred to a specialized asthma clinic to assess the indication of a biologic therapy. Patients were clinically phenotyped as T2-allergic, T2-eosinophilic, and non-T2. All patients underwent bronchoscopy, and systematic data collection of endoscopic findings, microbiology of bronchial aspirate, and presence of eosinophils in bronchial biopsy were recorded and compared between asthma phenotypes. Cluster analysis was performed accordingly. RESULTS: One hundred patients were recruited and classified as T2-allergic (28%), T2-eosinophilic (64%), and non-T2 (8%). On bronchoscopy, signs of gastroesophageal reflux disease were detected in 21%, vocal cord dysfunction in 5%, and tracheal abnormalities in 3%. Bronchial aspirate culture isolated bacteria in 27% of patients and fungi in 14%. Three clusters were identified: nonspecific, upper airway, and infection, the latter being less frequently associated with submucosal eosinophilia. Eosinophils were detected in 91% of bronchial biopsies. Despite a correlation to blood eosinophils, five patients with T2-phenotypes showed no eosinophils in bronchial biopsy, and three patients with non-T2 showed eosinophils in bronchial biopsy. Only one patient had moderate bleeding. INTERPRETATION: Routine bronchoscopy in SUA eligible for biologic therapy is a safe procedure that can help to better phenotype and personalize asthma management.

Inhibition of dopamine neurons prevents incentive value encoding of a reward cue: With revelations from deep phenotyping.

The survival of an organism is dependent on their ability to respond to cues in the environment. Such cues can attain control over behavior as a function of the value ascribed to them. Some individuals have an inherent tendency to attribute reward-paired cues with incentive motivational value, or incentive salience. For these individuals, termed sign-trackers, a discrete cue that precedes reward delivery becomes attractive and desirable in its own right. Prior work suggests that the behavior of sign-trackers is dopamine-dependent, and cue-elicited dopamine in the nucleus accumbens is believed to encode the incentive value of reward cues. Here we exploited the temporal resolution of optogenetics to determine whether selective inhibition of ventral tegmental area (VTA) dopamine neurons during cue presentation attenuates the propensity to sign-track. Using male tyrosine hydroxylase (TH)-Cre Long Evans rats it was found that, under baseline conditions, ∼84% of TH-Cre rats tend to sign-track. Laser-induced inhibition of VTA dopamine neurons during cue presentation prevented the development of sign-tracking behavior, without affecting goal-tracking behavior. When laser inhibition was terminated, these same rats developed a sign-tracking response. Video analysis using DeepLabCut revealed that, relative to rats that received laser inhibition, rats in the control group spent more time near the location of the reward cue even when it was not present and were more likely to orient towards and approach the cue during its presentation. These findings demonstrate that cue-elicited dopamine release is critical for the attribution of incentive salience to reward cues. Significance Statement: Activity of dopamine neurons in the ventral tegmental area (VTA) during cue presentation is necessary for the development of a sign-tracking, but not a goal-tracking, conditioned response in a Pavlovian task. We capitalized on the temporal precision of optogenetics to pair cue presentation with inhibition of VTA dopamine neurons. A detailed behavioral analysis with DeepLabCut revealed that cue-directed behaviors do not emerge without VTA dopamine. Importantly, however, when optogenetic inhibition is lifted, cue-directed behaviors increase, and a sign-tracking response develops. These findings confirm the necessity of VTA dopamine during cue presentation to encode the incentive value of reward cues.

Validation of a Pathological Score for the Assessment of Bronchial Biopsies in Severe Uncontrolled Asthma: Beyond Blood Eosinophils.

BACKGROUND: Blood eosinophil count (BEC) is currently used as a surrogate marker of T2 inflammation in severe asthma but its relationship with tissue T2-related changes is elusive. Bronchial biopsy could add reliable information but lacks standardization. OBJECTIVES: To validate a systematic assessment of the bronchial biopsy for the evaluation of severe uncontrolled asthma (SUA) by standardizing a pathological score. METHODS: A systematic assessment of submucosal inflammation, tissue eosinophilic count/field (TEC), goblet cells hyperplasia, epithelial changes, basement membrane thickening, prominent airway smooth muscle and submucosal mucous glands was initially agreed and validated in representative bronchial biopsies of 12 patients with SUA by 8 independent pathologists. In a second phase, 62 patients with SUA who were divided according to BEC≥300cells/mm3 or less underwent bronchoscopy with bronchial biopsies and the correlations between the pathological findings and the clinical characteristics were investigated. RESULTS: The score yielded good agreement among pathologists regarding submucosal eosinophilia, TEC, goblet cells hyperplasia and mucosal glands (ICC=0.85, 0.81, 0.85 and 0.87 respectively). There was a statistically significant correlation between BEC and TEC (r=0.393, p=0.005) that disappeared after correction by oral corticosteroids (OCS) use (r=0.170, p=0.307). However, there was statistically significant correlation between FeNO and TEC (r=0.481, p=0.006) that was maintained after correction to OCS use (r=0.419, p=0.021). 82.4% of low-BEC had submucosal eosinophilia, 50% of them moderate to severe. CONCLUSION: A standardized assessment of endobronchial biopsy is feasible and could be useful for a better phenotyping of SUA especially in those receiving OCS.

Inhibition of a cortico-thalamic circuit attenuates cue-induced reinstatement of drug-seeking behavior in "relapse prone" male rats.

RATIONALE: Relapse often occurs when individuals are exposed to stimuli or cues previously associated with the drug-taking experience. The ability of drug cues to trigger relapse is believed to be a consequence of incentive salience attribution, a process by which the incentive value of reward is transferred to the reward-paired cue. Sign-tracker (ST) rats that attribute enhanced incentive value to reward cues are more prone to relapse compared to goal-tracker (GT) rats that primarily attribute predictive value to such cues. OBJECTIVES: The neurobiological mechanisms underlying this individual variation in relapse propensity remains largely unexplored. The paraventricular nucleus of the thalamus (PVT) has been identified as a critical node in the regulation of cue-elicited behaviors in STs and GTs, including cue-induced reinstatement of drug-seeking behavior. Here we used a chemogenetic approach to assess whether "top-down" cortical input from the prelimbic cortex (PrL) to the PVT plays a role in mediating individual differences in relapse propensity. RESULTS: Chemogenetic inhibition of the PrL-PVT pathway selectively decreased cue-induced reinstatement of drug-seeking behavior in STs, without affecting behavior in GTs. In contrast, cocaine-primed drug-seeking behavior was not affected in either phenotype. Furthermore, when rats were characterized based on a different behavioral phenotype-locomotor response to novelty-inhibition of the PrL-PVT pathway had no effect on either cue- or drug-induced reinstatement. CONCLUSIONS: These results highlight an important role for the PrL-PVT pathway in vulnerability to relapse that is consequent to individual differences in the propensity to attribute incentive salience to discrete reward cues.

Hyperinflammatory State and Low T1 Adaptive Immune Response in Severe and Critical Acute COVID-19 Patients.

Background: A better understanding of COVID-19 immunopathology is needed to identify the most vulnerable patients and improve treatment options. Objective: We aimed to identify immune system cell populations, cytokines, and inflammatory markers related to severity in COVID-19. Methods: 139 hospitalized patients with COVID-19-58 mild/moderate and 81 severe/critical-and 74 recovered patients were included in a prospective longitudinal study. Clinical data and blood samples were obtained on admission for laboratory markers, cytokines, and lymphocyte subsets study. In the recovered patients, lymphocyte subsets were analyzed 8-12 weeks after discharge. Results: A National Early Warning Score 2 >2 (OR:41.4; CI:10.38-167.0), ferritin >583 pg/mL (OR:16.3; CI: 3.88-69.9), neutrophil/lymphocyte ratio >3 (OR: 3.5; CI: 1.08-12.0), sIL-2rα (sCD25) >512 pg/mL (OR: 3.3; CI: 1.48-7.9), IL-1Ra >94 pg/mL (OR: 3.2; IC: 1.4-7.3), and IL-18 >125 pg/mL (OR: 2.4; CI: 1.1-5.0) were associated with severe/critical COVID-19 in the multivariate models used. Lower absolute values of CD3, CD4, CD8, and CD19 lymphocytes together with higher frequencies of NK cells, a CD4 and CD8 activated (CD38+HLA-DR+) memory T cell and effector memory CD45RA+ (EMRA) phenotype, and lower T regulatory cell frequencies were found in severe/critical patients relative to mild/moderate and recovered COVID-19 patients. A significant reduction in Th1, Tfh1, and Tc1 with higher Th2, Tfh2, Tc2, and plasma cell frequencies was found in the most severe cases. Conclusion: A characteristic hyperinflammatory state with significantly elevated neutrophil/lymphocyte ratio and ferritin, IL-1Ra, sIL-2rα, and IL-18 levels together with a "low T1 lymphocyte signature" was found in severe/critical COVID-19 patients.