Acute Inflammatory Conditions Research Articles

Association of results of the glutaraldehyde coagulation test with plasma acute phase protein concentrations and hematologic findings in hospitalized cows.

The glutaraldehyde test (GAT) allows for animal-side semi-quantitative estimation of fibrinogen and gamma-globulin concentrations in blood samples of adult cattle and therefore detection of inflammatory disease conditions. However, the test has potential limitations, especially due to the latency period until sufficiently high fibrinogen and/or gamma-globulin concentrations are reached. The aim of the present study was therefore to assess the association between results of GAT with other inflammatory markers including hematologic variables, fibrinogen, plasma haptoglobin and serum amyloid A (SAA) concentrations. For the purpose of this prospective observational study, a convenience sample of 202 cows with a broad range of inflammatory and non-inflammatory clinical conditions was included. The GAT was run on EDTA blood, fibrinogen was measured using the Clauss and the heat precipitation method, and commercially available ELISA tests were used for determination of plasma haptoglobin and SAA concentrations. Shortened GAT coagulation times were more closely correlated to serum globulin (rs = -0.72) than to plasma fibrinogen concentrations measured with the heat precipitation (rs = -0.64) and the Clauss method (rs = -0.70). Cows with a markedly (≤3 min) or moderately (4-6 min) shortened coagulation time had higher (p < 0.001) plasma haptoglobin and SAA concentrations than cows with a negative test result. Total leukocyte, monocyte and neutrophil concentrations did not differ significantly between groups. An identified cut-off for the GAT coagulation time of ≤14 min had a sensitivity and specificity of 54.4 and 100%, respectively, for the prediction of an inflammatory state based on clinical findings and/or increased plasma haptoglobin or SAA concentrations. In conclusion, this study demonstrates considerable diagnostic agreement between positive GAT results and increased plasma concentrations of haptoglobin and SAA. Despite high specificity, the test lacks sensitivity in case of acute inflammatory conditions indicating that plasma acute phase protein concentrations and hematologic findings can provide additional diagnostic information if the GAT is negative.

Erianin alleviates LPS-induced acute lung injury via antagonizing P-selectin-mediated neutrophil adhesion function

Ethnopharmacological relevanceDendrobium officinale Kimura et Migo, known as “Tiepi Shihu” in traditional Chinese medicine, boasts an extensive history of medicinal use documented in the Chinese Pharmacopoeia. “Shen Nong Ben Cao Jing” records D. officinale as a superior herbal medicine for fortifying “Yin” and invigorating the five viscera. Erianin, a benzidine compound, emerges as a prominent active constituent derived from D. officinale, with the pharmacological efficacy of D. officinale closely linked to the anti-inflammatory properties of erianin. Aim of the studyAcute lung injury (ALI) is a substantial threat to global public health, while P-selectin stands out as a promising novel target for treating acute inflammatory conditions. This investigation aims to explore the therapeutic potential of erianin in ALI treatment and elucidate the underlying mechanisms. Experimental designThe effectiveness of erianin in conferring protection against ALI was investigated through comprehensive histopathological and biochemical analyses of lung tissues and bronchoalveolar lavage fluid (BALF) in an in vivo model of LPS-induced ALI in mice. The impact of erianin on fMLP-induced neutrophil chemotaxis was quantitatively assessed using the Transwell and Zigmond chamber, respectively. To determine the therapeutic target of erianin and elucidate their binding capability, a series of sophisticated assays were employed, including drug affinity responsive target stability (DARTS) assay, cellular thermal shift assay (CETSA), and molecular docking analyses. ResultsErianin demonstrated a significant alleviation of LPS-induced acute lung injury, characterized by reduced total cell and neutrophil counts and diminished total protein contents in BALF. Moreover, erianin exhibited a capacity to decrease proinflammatory cytokine production in both lung tissues and BALF. Notably, erianin effectively suppressed the activation of NF-κB signaling in the lung tissues of LPS- challenged mice; however, it did not exhibit in vitro inhibitory effects on inflammation in LPS-induced human pulmonary microvascular endothelial cells (HPMECs). Additionally, erianin blocked the adhesion and rolling of neutrophils on HPMECs. While erianin did not influence endothelial P-selectin expression or cytomembrane translocation, it significantly reduced the ligand affinity between P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1). ConclusionsErianin inhibits P-selectin-mediated neutrophil adhesion to activated endothelium, thereby alleviating ALI. The present study highlights the potential of erianin as a promising lead for ALI treatment.

Particles in Exhaled Air (PExA): Clinical Uses and Future Implications.

Access to distal airway samples to assess respiratory diseases is not straightforward and requires invasive procedures such as bronchoscopy and bronchoalveolar lavage. The particles in exhaled air (PExA) device provides a non-invasive means of assessing small airways; it captures distal airway particles (PEx) sized around 0.5-7 μm and contains particles of respiratory tract lining fluid (RTLF) that originate during airway closure and opening. The PExA device can count particles and measure particle mass according to their size. The PEx particles can be analysed for metabolites on various analytical platforms to quantitatively measure targeted and untargeted lung specific markers of inflammation. As such, the measurement of distal airway components may help to evaluate acute and chronic inflammatory conditions such as asthma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, and more recently, acute viral infections such as COVID-19. PExA may provide an alternative to traditional methods of airway sampling, such as induced sputum, tracheal aspirate, or bronchoalveolar lavage. The measurement of specific biomarkers of airway inflammation obtained directly from the RTLF by PExA enables a more accurate and comprehensive understanding of pathophysiological changes at the molecular level in patients with acute and chronic lung diseases.

Impact of Geospatial Food Access on Acute Pancreatitis Outcomes.

Food access is an important social determinant of health and refers to geographical and infrastructural aspects of food availability. Using publicly available data on food access from the United States Department of Agriculture (USDA), geospatial analyses can identify regions with variable food access, which may impact acute pancreatitis (AP), an acute inflammatory condition characterized by unpredictable outcomes and substantial mortality. This study aimed to investigate the association of clinical outcomes in patients with AP with geospatial food access. We examined AP-related hospitalizations at a tertiary center from January 2008 to December 2018. The physical addresses were geocoded through ArcGIS Pro2.7.0 (ESRI, Redlands, CA). USDA Food Access Research Atlas defined low food access as urban areas with 33% or more of the population residing over one mile from the nearest food source. Regression analyses enabled assessment of the association between AP outcomes and food access. The study included 772 unique patients with AP residing in Massachusetts with 931 AP-related hospitalizations. One hundred and ninety-eight (25.6%) patients resided in census tracts with normalurban food access and 574 (74.4%) patients resided in tracts with low food access. AP severity per revised Atlanta classification [OR 1.88 (95%CI 1.21-2.92); p = 0.005], and 30-day AP-related readmission [OR 1.78(95%CI 1.11-2.86); p = 0.02] had significant association with food access, despite adjustment for demographics, healthcare behaviors, and comorbidities (Charlson Comorbidity Index). However, food access lacked significant association with AP-related mortality (p = 0.40) and length of stay (LOS: p = 0.99). Low food access had a significant association with 30-day AP-related readmissions and AP severity. However, mortality and LOS lacked significant association with food access. The association between nutrition, lifestyle, and AP outcomes warrants further prospective investigation.

Venous Thrombosis in Acute Pancreatitis: What to and Not to Do?

Acute pancreatitis is an acute inflammatory condition of the pancreas that has not only local but systemic effects as well. Venous thrombosis is one such complication which can give rise to thrombosis of the peripheral vasculature in the form of deep vein thrombosis, pulmonary embolism, and splanchnic vein thrombosis. The prevalence of these complications increases with the severity of the disease and adds to the adverse outcomes profile. With better imaging and awareness, more cases are being detected, although many at times it can be an incidental finding. However, it remains understudied and strangely, most of the guidelines on the management of acute pancreatitis are silent on this aspect. This review offers an overview of the incidence, pathophysiology, symptomatology, diagnostic work-up, and management of venous thrombosis that develops in AP.

Distinct local and global functions of mouse Aβ low-threshold mechanoreceptors in mechanical nociception

The roles of Aβ low-threshold mechanoreceptors (LTMRs) in transmitting mechanical hyperalgesia and in alleviating chronic pain have been of great interest but remain contentious. Here we utilized intersectional genetic tools, optogenetics, and high-speed imaging to specifically examine functions of SplitCre labeled mouse Aβ-LTMRs in this regard. Genetic ablation of SplitCre-Aβ-LTMRs increased mechanical nociception but not thermosensation in both acute and chronic inflammatory pain conditions, indicating a modality-specific role in gating mechanical nociception. Local optogenetic activation of SplitCre-Aβ-LTMRs triggered nociception after tissue inflammation, whereas their broad activation at the dorsal column still alleviated mechanical hypersensitivity of chronic inflammation. Taking all data into consideration, we propose a model, in which Aβ-LTMRs play distinctive local and global roles in transmitting or alleviating mechanical hyperalgesia of chronic pain, respectively. Our model suggests a strategy of global activation plus local inhibition of Aβ-LTMRs for treating mechanical hyperalgesia.

The Role of Myeloid Cells in Thromboinflammatory Disease.

Inflammation contributes to the development of thrombosis, but the mechanistic basis for this association remains poorly understood. Innate immune responses and coagulation pathways are activated in parallel following infection or injury, and represent an important host defense mechanism to limit pathogen spread in the bloodstream. However, dysregulated proinflammatory activity is implicated in the progression of venous thromboembolism and arterial thrombosis. In this review, we focus on the role of myeloid cells in propagating thromboinflammation in acute inflammatory conditions, such as sepsis and coronavirus disease 2019 (COVID-19), and chronic inflammatory conditions, such as obesity, atherosclerosis, and inflammatory bowel disease. Myeloid cells are considered key drivers of thromboinflammation via upregulated tissue factor activity, formation of neutrophil extracellular traps (NETs), contact pathway activation, and aberrant coagulation factor-mediated protease-activated receptor (PAR) signaling. We discuss how strategies to target the intersection between myeloid cell-mediated inflammation and activation of blood coagulation represent an exciting new approach to combat immunothrombosis. Specifically, repurposed anti-inflammatory drugs, immunometabolic regulators, and NETosis inhibitors present opportunities that have the potential to dampen immunothrombotic activity without interfering with hemostasis. Such therapies could have far-reaching benefits for patient care across many thromboinflammatory conditions.

Metabolic plasticity of T cell fate decision.

The efficacy of adaptive immune responses in cancer treatment relies heavily on the state of the T cells. Upon antigen exposure, T cells undergo metabolic reprogramming, leading to the development of functional effectors or memory populations. However, within the tumor microenvironment (TME), metabolic stress impairs CD8 + T cell anti-tumor immunity, resulting in exhausted differentiation. Recent studies suggested that targeting T cell metabolism could offer promising therapeutic opportunities to enhance T cell immunotherapy. In this review, we provide a comprehensive summary of the intrinsic and extrinsic factors necessary for metabolic reprogramming during the development of effector and memory T cells in response to acute and chronic inflammatory conditions. Furthermore, we delved into the different metabolic switches that occur during T cell exhaustion, exploring how prolonged metabolic stress within the TME triggers alterations in cellular metabolism and the epigenetic landscape that contribute to T cell exhaustion, ultimately leading to a persistently exhausted state. Understanding the intricate relationship between T cell metabolism and cancer immunotherapy can lead to the development of novel approaches to improve the efficacy of T cell-based treatments against cancer.

CHF6297: a novel potent and selective p38 MAPK inhibitor with robust anti-inflammatory activity and suitable for inhaled pulmonary administration as dry powder.

Inhibition of p38 mitogen-activated protein kinase (MAPKs) is a potential therapeutic approach for the treatment of acute and chronic pulmonary inflammatory conditions. Here, we report the in vitro and in vivo characterization of the anti-inflammatory effects of CHF6297, a novel potent and selective p38α inhibitor designed for inhalation delivery as a dry powder formulation. CHF6297 has been proven to inhibit p38α enzymatic activity with sub-nanomolar potency (IC50 = 0.14 ± 0.06nM), with >1,000-fold selectivity against p38γ and p38δ. In human peripheral blood mononuclear cells (PBMCs) stimulated with lipopolysaccharides (LPS), as well as in human bronchial epithelial cells (BEAS2B) stimulated with TNF-α or cigarette smoke extract (CSE), CHF6297 inhibited interleukin (IL)-8 release with low nanomolar potency. CHF6297 administered to rats by using a nose-only inhalation device as a micronized dry powder formulation blended with lactose dose-dependently inhibited the LPS-induced neutrophil influx in the bronchoalveolar lavage fluid (BALF). CHF6297 administered intratracheally to rats dose-dependently counteracted the IL-1β (0.3mg/kg)-induced neutrophil influx (ED50 = 0.22mg/kg) and increase in IL-6 levels (ED50 = 0.82mg/kg) in the BALF. In mice exposed to tobacco smoke (TS), CHF6297, administered intranasally (i.n.) for 4 days at 0.03 or 0.3mg/kg, dose-dependently inhibited the corticosteroid-resistant TS-induced neutrophil influx in the BALF. In a murine house dust mite (HDM) model of asthma exacerbated by influenza virus A (IAV) (H3N3), CHF6297 (0.1mg/kg, i.n.) significantly decreased airway neutrophilia compared to vehicle-treated IAV/HDM-challenged mice. When CHF6297, at a dose ineffective per se (0.03mg/kg), was added to budesonide, it augmented the anti-inflammatory effects of the steroid. Overall, CHF6297 effectively counteracted lung inflammation in experimental models where corticosteroids exhibit limited anti-inflammatory activity, suggesting a potential for the treatment of acute exacerbations associated with chronic obstructive pulmonary disease (COPD) and asthma, acute lung injury (ALI), and viral-induced hyperinflammation.

Bruton’s tyrosine kinase inhibitors in brain diseases

Bruton&amp;rsquo;s tyrosine kinase (BTK) is a non-receptor-bound intracellular signaling protein. It is well known for its importance in the growth and malignancy of B cells, but recent studies suggested that the BTK is also associated with many other innate immune cells. As reported, a comparatively high level of BTK expression can be observed in monocytes, neutrophils, macrophages, and even central nervous system-resident immune cells like microglia. This suggests that BTK activation occurs in various acute and chronic inflammatory conditions. Here, we discuss how BTK inhibitors might be used to treat certain conditions, concentrating on ischemic stroke, multiple sclerosis, neuromyelitis optica spectrum disorders, and Alzheimer&amp;rsquo;s disease. We specifically show the significance of targeting B cells in controlling the inflammatory component of the disease in multiple sclerosis treatment. In addition, we draw attention to the role of BTK in the NLRP3 inflammasome activation, which is essential for brain damage and neuroinflammation. In summary, we conclude that therapeutic targeting of BTK in brain diseases is a potential strategy that can complement the existing therapies.

The etiologies of Kawasaki disease.

Kawasaki disease (KD) is a systemic vasculitis that affects young children and can result in coronary artery aneurysms. The etiology is currently unknown, but new clues from the epidemiology of KD in Japan, the country of highest incidence, are beginning to shed light on what may trigger this acute inflammatory condition. Additional clues from the global changes in KD incidence during the COVID-19 pandemic, coupled with a new birth cohort study from Japan, point to the potential role of person-to-person transmission of an infectious agent. However, the rising incidence of KD in Japan, with coherent waves across the entire country, points to an increasing intensity of exposure that cannot be explained by person-to-person spread. This Review discusses new and historical observations that guide us toward a better understanding of KD etiology and explores hypotheses and interpretations that can provide direction for future investigations. Once the etiology of KD is determined, accurate diagnostic tests will become available, and new, less expensive, and more effective targeted therapies will likely be possible. Clearly, solving the mystery of the etiologies of KD remains a priority for pediatric research.

Acute neutrophilic vasculitis (leukocytoclasia) in 36 COVID-19 autopsy brains

BackgroundHypercytokinemia, the renin-angiotensin system, hypoxia, immune dysregulation, and vasculopathy with evidence of immune-related damage are implicated in brain morbidity in COVID-19 along with a wide variety of genomic and environmental influences. There is relatively little evidence of direct SARS-CoV-2 brain infection in COVID-19 patients.MethodsBrain histopathology of 36 consecutive autopsies of patients who were RT-PCR positive for SARS-CoV-2 was studied along with findings from contemporary and pre-pandemic historical control groups. Immunostaining for serum and blood cell proteins and for complement components was employed. Microcirculatory wall complement deposition in the COVID-19 cohort was compared to historical control cases. Comparisons also included other relevant clinicopathological and microcirculatory findings in the COVID-19 cohort and control groups.ResultsThe COVID-19 cohort and both the contemporary and historical control groups had the same rate of hypertension, diabetes mellitus, and obesity. The COVID-19 cohort had varying amounts of acute neutrophilic vasculitis with leukocytoclasia in the microcirculation of the brain in all cases. Prominent vascular neutrophilic transmural migration was found in several cases and 25 cases had acute perivasculitis. Paravascular microhemorrhages and petechial hemorrhages (small brain parenchymal hemorrhages) had a slight tendency to be more numerous in cohort cases that displayed less acute neutrophilic vasculitis. Tissue burden of acute neutrophilic vasculitis with leukocytoclasia was the same in control cases as a group, while it was significantly higher in COVID-19 cases. Both the tissue burden of acute neutrophilic vasculitis and the activation of complement components, including membrane attack complex, were significantly higher in microcirculatory channels in COVID-19 cohort brains than in historical controls.ConclusionsAcute neutrophilic vasculitis with leukocytoclasia, acute perivasculitis, and associated paravascular blood extravasation into brain parenchyma constitute the first phase of an immune-related, acute small-vessel inflammatory condition often termed type 3 hypersensitivity vasculitis or leukocytoclastic vasculitis. There is a higher tissue burden of acute neutrophilic vasculitis and an increased level of activated complement components in microcirculatory walls in COVID-19 cases than in pre-pandemic control cases. These findings are consistent with a more extensive small-vessel immune-related vasculitis in COVID-19 cases than in control cases. The pathway(s) and mechanism for these findings are speculative.

Tissue-plasminogen activator effects on the phenotype of splenic myeloid cells in acute inflammation

Tissue-plasminogen activator (tPA) is a serine protease well known for its fibrinolytic function. Recent studies indicate that tPA could also modulate inflammation via plasmin generation and/or by receptor mediated signalling in vitro. However, the contribution of tPA in inflammatory processes in vivo has not been fully addressed. Therefore, using tPA-deficient mice, we have analysed the effect of lipopolysaccharide (LPS) challenge on the phenotype of myeloid cells including neutrophils, macrophages and dendritic cells (DCs) in spleen. We found that LPS treatment upregulated the frequency of major histocompatibility class two (MHCII+) macrophages but also, paradoxically, induced a deep downregulation of MHCII molecule level on macrophages and on conventional dendritic cells 2 (cDC2). Expression level of the CD11b integrin, known as a tPA receptor, was upregulated by LPS on MHCII+ macrophages and cDC2, suggesting that tPA effects could be amplified during inflammation. In tPA−/− mice under inflammatory conditions, expression of costimulatory CD86 molecules on MHCII+ macrophages was decreased compared to WT mice, while in steady state the expression of MHCII molecules was higher on macrophages. Finally, we reported that tPA deficiency slightly modified the phenotype of DCs and T cells in acute inflammatory conditions. Overall, our findings indicate that in vivo, LPS injection had an unexpectedly bimodal effect on MHCII expression on macrophages and DCs that consequently might affect adaptive immunity. tPA could also participate in the regulation of the T cell response by modulating the levels of CD86 and MHCII molecules on macrophages.

The Immunomodulatory Effects of Sulforaphane in Exercise-Induced Inflammation and Oxidative Stress: A Prospective Nutraceutical.

Sulforaphane (SFN) is a promising molecule for developing phytopharmaceuticals due to its potential antioxidative and anti-inflammatory effects. A plethora of research conducted in vivo and in vitro reported the beneficial effects of SFN intervention and the underlying cellular mechanisms. Since SFN is a newly identified nutraceutical in sports nutrition, only some human studies have been conducted to reflect the effects of SFN intervention in exercise-induced inflammation and oxidative stress. In this review, we briefly discussed the effects of SFN on exercise-induced inflammation and oxidative stress. We discussed human and animal studies that are related to exercise intervention and mentioned the underlying cellular signaling mechanisms. Since SFN could be used as a potential therapeutic agent, we mentioned briefly its synergistic attributes with other potential nutraceuticals that are associated with acute and chronic inflammatory conditions. Given its health-promoting effects, SFN could be a prospective nutraceutical at the forefront of sports nutrition.

FABP4 and Metabolite Profile in Lipopolysaccharide-Induced Mice Model Treated with Moringa oleifera Ethanol Leaf Extract

Sepsis, a life-threatening organ dysfunction resulting from a dysregulated host response to infection, induces changes in blood cells and metabolic alterations. Fatty acid binding protein 4 (FABP4), a lipid chaperone predominantly expressed in adipose tissue, is modulated in sepsis and may contribute to metabolic and immunologic changes. Moringa oleifera (M. oleifera) leaf extract (MOLE) is known to modulate immune system activity, but its potential for treating acute inflammatory conditions like sepsis remains unclear. This study investigates the ability of MOLE to modulate metabolite and hematological profiles in lipopolysaccharide (LPS)-induced sepsis in mice. Thirty-five male Swiss Webster mice (Mus musculus) were divided into five groups, including healthy control pre-treated with 0.5% carboxymethyl cellulose (CMC), an LPS-induced negative control, an LPS-induced positive control treated with dexamethasone (DMX) 7mg/KgBW/day and two MOLE treatment groups with doses of 5.6 and 11.2 mg/20 gBW. Mice received MOLE pre-treatment for three days before LPS induction. Three hours post-LPS injection, the LPS-induced group exhibited leukopenia (1.4 [0.9-2.5] x109 cells/L) and a 68.3% increase in triglyceride levels. However, the MOLE-treated group showed improved erythrocyte levels compared to the positive control group; [(9.9(9.3-10.0) x1012 cell/L) vs (7.7(7.0-9.0) x1012 cells/L), p&lt;0.05]. The study suggests that MOLE administration may positively impact sepsis conditions, particularly by enhancing RBC levels. Further research with an extended observation period is recommended to address limitations in metabolite level assessment.

Phthalate exposure increases interferon-γ during pregnancy: The Atlanta African American Maternal-Child Cohort

BackgroundThe immune system undergoes unique adaptations during pregnancy and is particularly sensitive to environmental chemicals, such as phthalates, which are associated with acute and chronic inflammatory medical conditions. However, current knowledge of how phthalate exposures are associated with systemic inflammation in pregnant people is limited by cross-sectional study designs and single chemical models. Our objective was to estimate the association between repeated measures of prenatal phthalate exposures, examined individually and collectively, and a panel of clinical inflammatory biomarkers. MethodsIn the Atlanta African American Maternal-Child Cohort, biospecimens were collected at mean 11 and 26 weeks gestation (N = 126). Concentrations of eight urinary phthalate metabolites and five serum inflammatory biomarkers, including CRP, IFN-γ, IL-6, IL-10, and TNF-α, were measured. Linear mixed effect regression and quantile g-computation models were used to estimate the associations for single phthalates and their exposure mixture, respectively. ResultsParticipants who self-reported any use of alcohol, tobacco, or marijuana in the month prior to pregnancy had increased MEP, MBP, MiBP, and CRP, relative to those with no substance use. IFN-γ was elevated in response to MECPP (% change = 17.35, 95 % confidence interval [CI] = 0.32, 32.27), MEHHP (% change = 12.75, 95 % CI = 2.22, 24.36), MEOHP (% change = 11.63, 95 % CI = 1.21, 23.12), and their parent phthalate, ΣDEHP (% change = 15.03, 95 % CI = 0.28, 31.94). The phthalate mixture was also associated with an increase in IFN-γ (% change = 15.03, 95 % CI = 6.18, 24.61). ConclusionsOur findings suggest DEHP metabolites induce systemic inflammation during pregnancy. The pro-inflammatory cytokine IFN-γ may play an important role in the relationship between prenatal phthalate exposures and adverse pregnancy outcomes.

Possible role of gut derived metabolites in communication between systemic inflammation and CNS in delirium development.

AbstractBackgroundDementia and delirium are strongly correlated. Patients with dementia are more prone to develop delirium, while delirium can lead to accelerated cognitive decline. Biomarkers present in the CSF have been considered to belong to the pathophysiological pathways between systemic inflammation, neuroinflammation, gut microbiota and consequently, contribute to the etiology of both the cognition impairments, ie. delirium and dementia. Despite multiple studies on inflammatory biomarkers in CSF, the link with systemic inflammation has still not been deciphered. Multiple studies have indicated that inflammatory pathways in patients with cognitive decline are mediated by gut microbiota.MethodIn this narrative review we screened PubMed for studies, where neuroinflammatory biomarkers detected in CSF were investigated in relation to delirium. We will explain the link to microbiome by comparing these delirium studies to microbiome studies in dementia. These studies were published in English till January 2023.ResultWe found that in patients with Alzheimer’s disease (AD) and delirium altered levels of at least 70 different neuroinflammatory biomarkers in CSF were found. Also altered microbiome has been identified in AD and its correlation with the CNS inflammation was shown. Interestingly, in case of AD, a recent study demonstrated that a microbial‐derived metabolite, trimethylamine N‐oxide (TMAO), reaches the CNS and that its elevated levels are present in AD patients.In case of delirium, we found two studies indicating contribution of disbalanced gut microbiota in acute CNS inflammation in human. It has been shown that preoperative status of gut microbiota can allow prediction of postoperative delirium in patients with gastric cancer. Interestingly, there was already one case described where fecal microbiota transplantation ameliorated patient’s infection and delirium. No studies on microbiome‐derived metabolites, which could constitute a possible link with the acute inflammation of CNS in delirium, have been found.ConclusionThere is irrefutable evidence that altered levels of neuroinflammatory biomarkers in CSF are associated with pathology of both AD and delirium. Implication of the microbiome, and microbial‐derived metabolite TMAO in inflammatory processes and in pathophysiology of AD has already been found. This has encouraged us to investigate the role of TMAO in the acute CNS inflammatory condition, i.e. delirium.

Real-Time High Throughput Technique to Quantify Neutrophil Extracellular Traps Formation in Human Neutrophils.

Neutrophils are myeloid-lineage cells that form a crucial part of the innate immune system. The past decade has revealed additional key roles that neutrophils play in the pathogenesis of cancer, autoimmune diseases, and various acute and chronic inflammatory conditions by contributing to the initiation and perpetuation of immune dysregulation through multiple mechanisms, including the formation of neutrophil extracellular traps (NETs), which are structures crucial in antimicrobial defense. Limitations in techniques to quantify NET formation in an unbiased, reproducible, and efficient way have restricted our ability to further understand the role of neutrophils in health and diseases. We describe an automated, real-time, high-throughput method to quantify neutrophils undergoing NET formation using a live cell imaging platform coupled with a membrane permeability-dependent dual-dye approach using two different DNA dyes to image intracellular and extracellular DNA. This methodology is able to help assess neutrophil physiology and test molecules that can target NET formation.

Myeloid Derived Suppressor Cell Kinetics in Peripheral Blood Correlate with Efficacy and Toxicity of CAR T Cell Therapy in Relapsed or Refractory B Cell Lymphoma

Introduction. CAR T-cell therapy is potentially curative for patients with relapsed or refractory B-cell lymphoma (BCL). However, about 60% of patients fail CAR T-cell therapy. Immune-related adverse events (irAE) like cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS) occur in an inflammatory state. Myeloid-derived suppressor cells (MDSCs) expand during acute inflammation as steady-state hematopoiesis switches to emergency myelopoiesis. We hypothesized that the acute inflammatory conditions created by CAR T-cell therapy may alter MDSC kinetics and investigated MDSC expansion in the context of CAR T-cell efficacy and toxicity in BCL. Methods. Patients with BCL receiving standard-of-care CAR T-cell therapy were enrolled in a prospective sample collection study. Blood samples were collected before lymphodepletion (baseline), prior to and at early intervals after CAR T-cell infusion. Viable white blood cell (WBC) and MDSC counts were evaluated by multicolor flow cytometry. Phenotypically, MDSCs were defined as immature myeloid cells (CD11b + CD33 + HLA-DR -/low IL-4R +) and divided into monocytic (M-MDSC, CD14 +) and polymorphonuclear (PMN-MDSC, CD15 +) subsets. Clinical response was assessed by Lugano criteria at 1, 3 and 6 months. Incidence and severity of CRS and ICANS were recorded. Cell counts were analyzed by descriptive statistics and reported as mean ± standard error or fold-change from baseline. Kinetics of MDSCs in blood and correlation with clinical outcomes were evaluated by Wilcoxon matched pair signed rank t-test and Mann Whitney U-test. Results. Forty-three BCL patients (41 large BCL, 2 mantle cell lymphoma) were enrolled in the study. Median age was 64 (range 27-83), 32.6% were female. Racial and ethnic minority groups represented 14% of enrolled subjects. One patient developed grade 5 ICANS and was not evaluable for response. Thirty-seven (86%) developed leukopenia and all received granulocyte colony stimulating factor (G-CSF) starting on day 5 post-CAR T infusion. WBC count fell sharply from baseline following lymphodepletion (7.7E +05±8.6E +04 baseline vs 2.9E +05±9.2E +04/mL, p&amp;lt;0.0001) and continued to decline 2-3 days post-CAR T infusion (baseline vs 1.4E +05±2.1E +04/mL, p&amp;lt;0.0001) before returning to baseline within 1 week post-CAR T (i.e. within 3 days of G-CSF). MDSCs followed similar kinetics early on but significantly increased from baseline levels by 1-week post-CAR T (3.4E +03±5.8E +02 baseline vs 8.5E +03±1.7E +02 /mL, p&amp;lt;0.0001). This effect was mainly driven by an exuberant expansion of M-MDSC observed in 33/43 patients (median 6.1-fold increase from baseline at 1 week, range 0.5-4301). Seven patients (16.3%) had progressive disease (PD) at 1 month, 6 (13.9%) additional patients progressed at 3 months and 4 (9.3%) more progressed at 6 months after CAR T-cell infusion. M-MDSC expansion 1-week post-CAR T was only observed in 3/7 refractory patients compared with 28/35 responding patients (Fisher's exact test, p=0.0635). Patients who progressed at 3 months had poorer M-MDSC retention compared to patients with sustained response (1.7E +02±6.1E +01 PD vs 1.4E +03±2.4E +01/mL at 2-week post-infusion, p&amp;lt;0.1). Similarly, patients who progressed at 6 months had lower M-MDSC compared with sustained responders (2.0E +02±8.1E +01 PD vs 4.5E +02±1.4E +02 ml at 1-month post-infusion, p&amp;lt;0.05). Thirteen patients (30.2%) developed &amp;gt; grade 2 CRS and had lower PMN-MDSC retention rate 2-3 days post-CAR-T compared with those with no/low-grade CRS (4.4E +02±2.6E +02 vs 1.4E +03±3.9E +02/mL, p&amp;lt;0.05). Similarly, patients who had ICANS &amp;gt; grade 2 (n=14, 32.5%) had lower PMN-MDSC early retention compared to those with no or low-grade ICANS (5.0E +02±2.5E +02 vs 1.5E +03±4.1E +02/mL, p&amp;lt;0.05). Further analyses are currently underway to bridge these findings with the kinetics of CAR T-cells and T-cell repertoire post-CAR T. Conclusions. The proinflammatory milieu after CAR-T and the use of G-CSF can lead to significant expansion of M-MDSCs. Rather than an impediment to CAR T therapy, M-MDSC expansion and retention are associated with favorable clinical response and PMN-MDSC with a lower risk of developing high grades CRS or ICANS. Whether MDSCs play a mechanistic role remains to be elucidated, but they may have a role as a biomarker in predicting outcomes after CAR T-cell therapy in BCL.

Resident Memory-like CD8+ T Cells Are Involved in Chronic Inflammatory and Neurodegenerative Diseases in the CNS.

Resident memory T (Trm) cells are a unique population that can survive and function in a compartmentalized tissue with inflammatory potential. We aim to investigate the alteration of Trm population in acute/chronic inflammatory and neurodegenerative diseases in the CNS. The frequencies of CD4+ and CD8+ T cells expressing both CD69 and CD103, the markers for Trm cells, were quantified in the peripheral blood and CSF (n = 80 and 44, respectively) in a cross-sectional manner. The transcriptional profile of Trm-like population in the CSF was further analyzed using a public single-cell dataset. The frequency of CD69+CD103+CD8+ T cells was strikingly higher in the CSF than in the peripheral blood (among memory fraction, 13.5% vs 0.11%, difference (mean [SE]): 13.4% [2.9]). This CD69+CD103+CD8+ T-cell population was increased in the CSF from patients with chronic inflammatory diseases including multiple sclerosis and with neurodegenerative diseases such as Parkinson disease and Alzheimer disease compared with controls (11.5%, 13.0%, 8.1% vs 2.9%, respectively). By contrast, the frequency was not altered in acute inflammatory conditions in the CNS (4.0%). Single-cell RNAseq analysis confirmed Trm signature in CD69+CD103+CD8+ T cells in the CSF, supporting their Trm-like phenotype, which was not clear in controls. Collectively, an increase in CD69+CD103+CD8+ Trm-like population in the CSF is related with both chronic neuroinflammatory and some neurodegenerative diseases in the CNS, suggesting a partially shared pathology in these diseases.