Regulation of leucocyte homeostasis in the circulation

Evaluation of safety and biomedical potential of water-soluble oat lignin Avena sativa L

The study of the value of lignin for biomedical use is generating growing interest. For the first time, the safety and biological efficacy of lignin from the stems of the oat Avena sativa L. were studied, necessary for a preliminary assessment of its biomedical potential, have been studied. In vitro experiments, a sample of oat lignin exhibited cytotoxicity to the HeLa, A549, and HT-29 cancer cell lines, depending on the concentration. At maximum concentrations 125 and 150 μg/ml, it reduced their survival and increased the level of reactive oxygen species. In vivo experiments, a sample of oat lignin, with acute (from 5 to 250 mg/kg body weight) and chronic (300, 1200 and 2000 mg/kg body weight) administration, did not have a toxic or genotoxic effect on the organs of mice. The biological efficacy of the oat lignin was manifested in activation of repair processes in bone marrow and thyroid gland, a decrease in the level of abnormal spermatozoa in males, stimulation of reproductive performance of females and in increase in research activity and a decrease in the level of anxiety in animals. The results indicate the prospects for further study of the medical and biological potential lignin of the oat.

Analyzing urinary hippuric acid as a metabolic health biomarker through a supramolecular architecture

The prevalence of metabolic disorders has been found to increase concomitantly with alternations in habitual diet and lifestyle, indicating the importance of metabolic health monitoring for early warning of high-risk status and suggesting effective intervention strategies. Hippuric acid (HA), as one of the most abundant metabolites from the gut microbiota, holds potential as a regulator of metabolic health. Accordingly, it is imperative to establish an efficient, sensitive, and affordable method for large-scale population monitoring, revealing the association between HA level and metabolic disorders. Upon systematic screening of macrocycle•dye reporter pair, a supramolecular architecture (guanidinomethyl-modified calix[5]arene, GMC5A) was employed to sense urinary HA by employing fluorescein (Fl), whose complexation behavior was demonstrated by theoretical calculations, accomplishing quantification of HA in urine from 249 volunteers in the range of 0.10 mM and 10.93 mM. Excitedly, by restricted cubic spline, urinary HA concentration was found to have a significantly negative correlation with the risk of metabolic disorders when it exceeded 0.76 mM, suggesting the importance of dietary habits, especially the consumption of fruits, coffee, and tea, which was unveiled from a simple questionnaire survey. In this study, we accomplished a high throughput and sensitive detection of urinary HA based on supramolecular sensing with the GMC5A•Fl reporter pair, which sheds light on the rapid quantification of urinary HA as an indicator of metabolic health status and early intervention by balancing the daily diet.

The impact of everolimus on hematologic parameters in patients with renal angiomyolipoma associated with tuberous sclerosis complex

BACKGROUND

Everolimus is an effective treatment for renal angiomyolipoma associated with TSC (TSC-RAML). However, its impact on hematologic parameters in TSC-RAML patients remains unclear.

METHODS

Hematologic data were collected from TSC-RAML patients undergoing everolimus treatment in two registered clinical trials. Dynamic changes in hematologic parameters during treatment were analyzed. Additionally, we also explored variations in hematologic impact based on gender and age within the patient population.

RESULT

A total of 55 patients from the two clinical trials are included in this analysis. Hemoglobin, white blood cells (WBC), lymphocytes, neutrophils, and platelet showed significant decreases during everolimus treatment (P < 0.05). However, the decline in hemoglobin, WBC, and neutrophils attenuated by the 12th month (P ≥ 0.05). Aspartate transaminase (AST), Alanine transferase (ALT), total cholesterol (TC), and triglyceride (TG) increased significantly during everolimus treatment (P < 0.05), and these increases persisted throughout the year-long treatment. Hemoglobin decreased significantly more in male patients (- 15 vs - 6, P = 0.010), and AST showed a more significant increase in males (7.0 vs 3.0, P = 0.041). Platelet counts decreased significantly more in younger patients (≤ 30 years old) compared to older patients (- 50 vs - 14, P = 0.020).

CONCLUSION

Everolimus administration in TSC-RAML patients may increase hematologic risks, with male and younger patients potentially exhibiting greater susceptibility to these effects.

The Relationship of Immune Markers with Severity and Heritability of Depressive Disorder: A Cross-Sectional Hospital-Based Study from North India

Background

Inflammatory response plays a pivotal role in the pathophysiology of depression. With this background, we planned this study to see if immune markers, interleukin 6 (IL-6), and erythrocyte sedimentation rate (ESR) are raised in subjects with major depressive disorder (MDD) and compare its level with healthy controls and first-degree relatives of subjects. We also explored if variation in the level of these markers was related to the severity of depression.

Methods

This comparative observational study included 120 subjects, who were divided into three groups of 40 individuals each. Group 1 was the MDD group, group 2 was the healthy first-degree relative group, and group 3 was the healthy control group. All the subjects were then made to undergo estimation of IL-6 (pg/mL) and ESR (mm/h) from our hospital biochemistry lab. The patients in group 1 were additionally screened for the severity of depression.

Results

The mean IL-6 and ESR measure within the MDD group was 9.20 ± 13.40 (pg/mL) and 5.90 ± 5.35 (mm/h), respectively. We found that the mean and median values of both IL-6 and ESR were highest in the MDD group as compared to other groups, which were statistically significant (p <0.05). A pairwise comparison found no significant difference in the IL-6 and ESR scores among the healthy controls and healthy first-degree relatives. The mean of IL-6 was highest in individuals with moderate severity of depression, while the mean of ESR was highest in individuals with severe depression.

Conclusion

The immune markers, IL-6 and ESR, were significantly raised in the MDD group; however, the levels did not correlate significantly with the differential severity of the depressive disorder as per Hamilton depression rating scale (HAM-D) scores.

Safety and effectiveness of sarilumab in Japanese patients with rheumatoid arthritis refractory to previous treatments: An interim analysis of a post-marketing surveillance

OBJECTIVES

An interim analysis of post-marketing surveillance data to assess the safety and effectiveness of sarilumab in Japanese patients with rheumatoid arthritis refractory to previous treatment.

METHODS

The interim analysis included patients who initiated sarilumab therapy between June 2018 and January 2021. The primary objective of this surveillance was safety.

RESULTS

In total, 1036 patients were enrolled and registered by 12 January 2021 (interim cut-off date). Of these, 678 were included in the safety analysis [75.4% female; mean age (± standard deviation) 65.8 ± 13.0 years]. Adverse drug reactions, defined as adverse events classified as possibly or probably related to sarilumab, were reported in 170 patients (incidence: 25.1%), with white blood cell count decreased (4.4%) and neutrophil count decreased (1.6%) most frequently reported. Serious haematologic disorders (3.4%) and serious infections (including tuberculosis) (2.5%) were the most frequently reported priority surveillance items. No malignant tumour was reported. An absolute neutrophil count (ANC) below the minimum standard value did not increase the incidence of serious infections.

CONCLUSIONS

Sarilumab was well tolerated, and no new safety signals were noted in this analysis. There was no difference in the frequency of serious infections between patients with an ANC below or above normal.

Circadian Effects on Vascular Immunopathologies

Circadian rhythms exert a profound impact on most aspects of mammalian physiology, including the immune and cardiovascular systems. Leukocytes engage in time-of-day-dependent interactions with the vasculature, facilitating the emigration to and the immune surveillance of tissues. This review provides an overview of circadian control of immune-vascular interactions in both the steady state and cardiovascular diseases such as atherosclerosis and infarction. Circadian rhythms impact both the immune and vascular facets of these interactions, primarily through the regulation of chemoattractant and adhesion molecules on immune and endothelial cells. Misaligned light conditions disrupt this rhythm, generally exacerbating atherosclerosis and infarction. In cardiovascular diseases, distinct circadian clock genes, while functioning as part of an integrated circadian system, can have proinflammatory or anti-inflammatory effects on these immune-vascular interactions. Here, we discuss the mechanisms and relevance of circadian rhythms in vascular immunopathologies.

Made to order: emergency myelopoiesis and demand-adapted innate immune cell production

Definitive haematopoiesis is the process by which haematopoietic stem cells, located in the bone marrow, generate all haematopoietic cell lineages in healthy adults. Although highly regulated to maintain a stable output of blood cells in health, the haematopoietic system is capable of extensive remodelling in response to external challenges, prioritizing the production of certain cell types at the expense of others. In this Review, we consider how acute insults, such as infections and cytotoxic drug-induced myeloablation, cause molecular, cellular and metabolic changes in haematopoietic stem and progenitor cells at multiple levels of the haematopoietic hierarchy to drive accelerated production of the mature myeloid cells needed to resolve the initiating insult. Moreover, we discuss how dysregulation or subversion of these emergency myelopoiesis mechanisms contributes to the progression of chronic inflammatory diseases and cancer.

Self-Oxidated Hydrophilic Chitosan Fibrous Mats for Fatal Hemorrhage Control

Enriching erythrocytes and platelets in seconds and providing a fast seal in bleeding sites is vital to fatal hemorrhage control. Herein, hydrophilic chitosan fibrous mats (CECS-D mats) are fabricated by introducing hydrophilic carboxyethyl groups and subsequent catechol groups onto chitosan fibers. Due to strong hydrophilicity, CECS-D mats exhibit rapid liquid-absorption capacity, especially instantaneous absorptivity to the rabbit blood, which can achieve erythrocyte and platelet aggregations quickly by concentrating blood, thus promoting the formation of blood clots. Furthermore, the mats are self-oxidated to form quinone-amine adducts or quinone multimers by adjusting pH conditions, which not only provides tissue adhesion but also induces erythrocyte aggregation and platelet adhesion, further enhancing the seal and triggering quick closure to achieve fast hemostasis. Therefore, the mats reveal superior hemostatic performance in rabbit liver and spleen models over CECS mats and gauze. Especially in the fatal femoral artery injury model of rabbits, the mats reduce the blood loss by ∼75% and shortened the bleeding time by ∼50% compared with CECS mats, which have been reported to have the same hemostatic effect as commercialized Celox products in a swine femoral artery injury model. Besides, the mats are cytocompatible and degradable as well as antibacterial. This chitosan mat is a promising hemostatic material for fatal hemorrhage control.

Effect of dietary oregano essential oil and milk replacer on physiological status and immunological responses of pre- and post-weaned Ghoongroo piglets

Ghoongroo pigs have good adaptability in a low input production system with high prolificacy. The present study was conducted on pre-and post-weaned Ghoongroo piglets from 2-3 days to 12 weeks of age to evaluate the effect of a milk replacer and oregano essential oil (EO) on growth, physiological and immunological responses. Thirty six piglets were randomly divided into three groups. The control group (n = 12) was allowed to suck mother's milk. Second group piglets were provided milk replacer (MR) and piglets of the third group were provided milk replacer along with oregano EO at 500 mg/kg diet. After weaning, piglets were provided standard concentrate diets. The results showed that the body weight in MR and MR + EO groups were significantly higher compared with the control. The MR + EO group had better intestinal microbiota, greater nonspecific innate immunity with the phagocytosis efficacy of neutrophils, lower cortisol concentration and more stable thyroid hormones than the other groups. The better haematological status supported the rapid organ development and improved intestinal health status in both the experimental groups. In conclusion, milk replacer, especially with the inclusion of oregano EO, can lower weaning stress, enhance nonspecific immunity and improve growth and health status of piglets.

Effects of 3-week repeated cold water immersion on leukocyte counts and cardiovascular factors: an exploratory study

Aim: This exploratory study aimed to investigate the effects of a 3-week repeated cold water immersion (CWI) intervention on leukocyte counts and cardiovascular factors (mean arterial pressure [MAP], heart rate [HR]) in healthy men. Methods: A total of n = 12, non-cold-adapted men (age: 25.2 ± 4.0 years; height: 177.8 ± 5.6 cm; weight: 73.8 ± 6.5 kg) were randomly allocated to the CWI or control (CON) group. The CWI group underwent a 3-week repeated CWI intervention (12min at 7°C, 4x/week). The CON group did not receive any cold exposure or therapy. Total leukocyte numbers and proportions (neutrophils, basophils, eosinophils, monocytes, lymphocytes) and cardiovascular factors (MAP, HR) were assessed at baseline and after the 3-week intervention period. Results: Total leukocyte count decreased in CWI (p = 0.027, 95% CI -2.35 to -0.20 × 103/µL) and CON (p = 0.043, 95% CI -2.75 to -0.50 × 103/µL). CWI showed a decrease in neutrophil number (p = 0.028, 95% CI -1.55 to -0.25 × 103/µL) and proportion (p = 0.046, 95% CI -6.42 to 0.56%). In contrast, CON showed no significant change (p > 0.05). No differences were found for other leukocyte subtypes in CWI or CON (all p > 0.05). MAP (p = 0.028, 95% CI -17 to -8 mmHg) and HR (p = 0.027, 95% CI -7 to -2 bpm) were reduced in CWI, whereas CON showed no change (p > 0.05). Conclusion: The results suggest no relevant effects of 3-week repeated CWI on leukocyte counts in healthy men. Due to methodological limitations, the effects on the investigated cardiovascular factors remain unclear. Further studies with larger sample sizes are needed to examine the effects on immune function and cardiovascular health.

Investigating the effects of maltreatment and acute stress on the concordance of blood and DNA methylation methods of estimating immune cell proportions

BACKGROUND

Immune cell proportions can be used to detect pathophysiological states and are also critical covariates in genomic analyses. The complete blood count (CBC) is the most common method of immune cell proportion estimation, but immune cell proportions can also be estimated using whole-genome DNA methylation (DNAm). Although the concordance of CBC and DNAm estimations has been validated in various adult and clinical populations, less is known about the concordance of existing estimators among stress-exposed individuals. As early life adversity and acute psychosocial stress have both been associated with unique DNAm alterations, the concordance of CBC and DNAm immune cell proportion needs to be validated in various states of stress.

RESULTS

We report the correlation and concordance between CBC and DNAm estimates of immune cell proportions using the Illumina EPIC DNAm array within two unique studies: Study 1, a high-risk pediatric cohort of children oversampled for exposure to maltreatment (N = 365, age 8 to 14 years), and Study 2, a sample of young adults who have participated in an acute laboratory stressor with four pre- and post-stress measurements (N = 28, number of observations = 100). Comparing CBC and DNAm proportions across both studies, estimates of neutrophils (r = 0.948, p < 0.001), lymphocytes (r = 0.916, p < 0.001), and eosinophils (r = 0.933, p < 0.001) were highly correlated, while monocyte estimates were moderately correlated (r = 0.766, p < 0.001) and basophil estimates were weakly correlated (r = 0.189, p < 0.001). In Study 1, we observed significant deviations in raw values between the two approaches for some immune cell subtypes; however, the observed differences were not significantly predicted by exposure to child maltreatment. In Study 2, while significant changes in immune cell proportions were observed in response to acute psychosocial stress for both CBC and DNAm estimates, the observed changes were similar for both approaches.

CONCLUSIONS

Although significant differences in immune cell proportion estimates between CBC and DNAm exist, as well as stress-induced changes in immune cell proportions, neither child maltreatment nor acute psychosocial stress alters the concordance of CBC and DNAm estimation methods. These results suggest that the agreement between CBC and DNAm estimators of immune cell proportions is robust to exposure to child maltreatment and acute psychosocial stress.

Beyond lymphopenia, unraveling radiation-induced leucocyte subpopulation kinetics and mechanisms through modeling approaches

Leucocyte subpopulations in both lymphoid and myeloid lineages have a significant impact on antitumor immune response. While radiation-induced lymphopenia is being studied extensively, radiation effects on lymphoid and myeloid subtypes have been relatively less addressed. Interactions between leucocyte subpopulations, their specific radiation sensitivity and the specific kinetics of each subpopulation can be modeled based on both experimental data and knowledge of physiological leucocyte depletion, production, proliferation, maturation and homeostasis. Modeling approaches of the leucocyte kinetics that may be used to unravel mechanisms underlying radiation induced-leucopenia and prediction of changes in cell counts and compositions after irradiation are presented in this review. The approaches described open up new possibilities for determining the influence of irradiation parameters both on a single-time point of acute effects and the subsequent recovery of leukocyte subpopulations. Utilization of these approaches to model kinetic data in post-radiotherapy states may be a useful tool for further development of new treatment strategies or for the combination of radiotherapy and immunotherapy.

Effects of dietary antioxidant supplementation on metabolism and inflammatory biomarkers in heat-stressed dairy cows

Heat-stress-induced inflammation may be ameliorated by antioxidant supplementation due to the purported effects of increased production of reactive oxygen species or oxidative stress on the gastrointestinal tract barrier. Thus, study objectives were to evaluate whether antioxidant supplementation [AGRADO Plus 2.0 (AP); EW Nutrition] affects metabolism and inflammatory biomarkers in heat-stressed lactating dairy cows. Thirty-two mid-lactation multiparous Holstein cows were assigned to 1 of 4 dietary-environmental treatments: (1) thermoneutral (TN) conditions and fed a control diet (TN-CON; n = 8), (2) TN and fed a diet with AP (10 g antioxidant; n = 8), (3) heat stress (HS) and fed a control diet (HS-CON; n = 8), or (4) HS and fed a diet with AP (HS-AP; n = 8). The trial consisted of a 23-d prefeeding phase and 2 experimental periods (P). Respective dietary treatments were top-dressed starting on d 1 of the prefeeding period and continued daily throughout the duration of the experiment. During P1 (4 d), baseline data were collected. During P2 (7 d), HS was artificially induced using an electric heat blanket (Thermotex Therapy Systems Ltd.). During P2, the effects of treatment, day, and treatment-by-day interaction were assessed using PROC MIXED of SAS (SAS Institute Inc.). Heat stress (treatments 3 and 4) increased rectal, vaginal, and skin temperatures (1.2°C, 1.1°C, and 2.0°C, respectively) and respiration rate (33 breaths per minute) relative to TN cows. As expected, HS decreased dry matter intake, milk yield, and energy-corrected milk yield (32%, 28%, and 28% from d 4 to 7, respectively) relative to TN. There were no effects of AP on body temperature indices or production. Milk fat, protein, and lactose concentrations remained unaltered by HS or AP; however, milk urea nitrogen was increased during HS regardless of AP supplementation (26% relative to TN). Circulating glucose remained unchanged by HS, AP, or time. Additionally, HS decreased circulating glucagon (29% from d 3 to 7 relative to TN), but there was no additional effect of AP. There was a tendency for nonesterified fatty acid concentrations to be increased in HS-AP cows throughout P2 (60% relative to TN-CON), whereas it remained similar in all other treatments. Blood urea nitrogen increased for both HS treatments from d 1 to 3 before steadily decreasing from d 5 to 7, with the overall increase being most pronounced in HS-CON cows (27% relative to TN-CON). Further, supplementing AP decreased blood urea nitrogen in HS-AP on d 3 relative to HS-CON (15%). Circulating serum amyloid A tended to be and lipopolysaccharide binding protein was increased by HS, but neither acute-phase protein was affected by AP. Overall, AP supplementation appeared to marginally alter metabolism but did not meaningfully alter inflammation during HS.

The relationship between neutrophil-to-lymphocyte ratio and cerebral collateral circulation in patients with symptomatic severe intracranial artery stenosis or occlusion

BACKGROUND

The neutrophil/lymphocyte ratio (NLR) has been considered a prognostic indicator for determining the systemic inflammatory response and atherosclerosis. We aimed to determine the relationship between NLR and the development of cerebral collateral circulation in patients with symptomatic severe stenosis or occlusion of intracranial arteries.

METHODS

All patients underwent digital subtraction angiography (DSA) within 14 days of admission and were divided into a group with good collateral circulation (77 patients) and a group with poor collateral circulation (86 patients) according to the DSA collateral compensation grading method. Apo B, total cholesterol, LDL, and Neutrophil count in the poor side branch group were significantly higher than in the good side branch group. Multifactorial analysis showed that high NLR levels were a valid predictor of poor collateral circulation in patients with symptomatic severe intracranial artery stenosis or occlusion. Spearman correlation analysis showed that the size of the collateral branch score was negatively correlated with NLR (r = -0.509, P < 0.001) and cholesterol content (r = -0.249, P = 0.002). NLR predicted poor collateral circulation with an AUC of 0.620 (sensitivity 66.7 %, specificity 61.3 %, 95 % CI = 0.517-0.723,P < 0.05).

CONCLUSION

We demonstrate a correlation between NLR levels and the development of collateral circulation in the brain in patients with symptomatic severe stenosis or occlusion of the intracranial arteries.

DNA Methylation Alterations in Fractionally Irradiated Rats and Breast Cancer Patients Receiving Radiotherapy

Radiation-Induced CardioVascular Disease (RICVD) is an important concern in thoracic radiotherapy with complex underlying pathophysiology. Recently, we proposed DNA methylation as a possible mechanism contributing to RICVD. The current study investigates DNA methylation in heart-irradiated rats and radiotherapy-treated breast cancer (BC) patients. Rats received fractionated whole heart X-irradiation (0, 0.92, 6.9 and 27.6 Gy total doses) and blood was collected after 1.5, 3, 7 and 12 months. Global and gene-specific methylation of the samples were evaluated; and gene expression of selected differentially methylated regions (DMRs) was validated in rat and BC patient blood. In rats receiving an absorbed dose of 27.6 Gy, DNA methylation alterations were detected up to 7 months with differential expression of cardiac-relevant DMRs. Of those, SLMAP showed increased expression at 1.5 months, which correlated with hypomethylation. Furthermore, E2F6 inversely correlated with a decreased global longitudinal strain. In BC patients, E2F6 and SLMAP exhibited differential expression directly and 6 months after radiotherapy, respectively. This study describes a systemic radiation fingerprint at the DNA methylation level, elucidating a possible association of DNA methylation to RICVD pathophysiology, to be validated in future mechanistic studies.

Antiatherosclerotic Effects of CSL112 Mediated by Enhanced Cholesterol Efflux Capacity

Approximately 12% of patients with acute myocardial infarction (AMI) experience a recurrent major adverse cardiovascular event within 1 year of their primary event, with most occurring within the first 90 days. Thus, there is a need for new therapeutic approaches that address this 90-day post-AMI high-risk period. The formation and eventual rupture of atherosclerotic plaque that leads to AMI is elicited by the accumulation of cholesterol within the arterial intima. Cholesterol efflux, a mechanism by which cholesterol is removed from plaque, is predominantly mediated by apolipoprotein A-I, which is rapidly lipidated to form high-density lipoprotein in the circulation and has atheroprotective properties. In this review, we outline how cholesterol efflux dysfunction leads to atherosclerosis and vulnerable plaque formation, including inflammatory cell recruitment, foam cell formation, the development of a lipid/necrotic core, and degradation of the fibrous cap. CSL112, a human plasma-derived apolipoprotein A-I, is in phase 3 of clinical development and aims to reduce the risk of recurrent cardiovascular events in patients with AMI in the first 90 days after the index event by increasing cholesterol efflux. We summarize evidence from preclinical and clinical studies suggesting that restoration of cholesterol efflux by CSL112 can stabilize plaque by several anti-inflammatory/immune-regulatory processes. These effects occur rapidly and could stabilize vulnerable plaques in patients who have recently experienced an AMI, thereby reducing the risk of recurrent major adverse cardiovascular events in the high-risk early post-AMI period.

Characterization of a novel microfluidic platform for the isolation of rare single cells to enable CTC analysis from head and neck squamous cell carcinoma patients

Detailed examination of tumor components is leading‐edge to establish personalized cancer therapy. Accompanying research on cell‐free DNA, the cell count of circulating tumor cells (CTCs) in patient blood is seen as a crucial prognostic factor. The potential of CTC analysis is further not limited to the determination of the overall survival rate but sheds light on understanding inter‐ and intratumoral heterogeneity. In this regard, commercial CTC isolation devices combining an efficient enrichment of rare cells with a droplet deposition of single cells for downstream analysis are highly appreciated. The Liquid biopsy platform CTCelect was developed to realize a fully‐automated enrichment and single cell dispensing of CTCs from whole blood without pre‐processing. We characterized each process step with two different carcinoma cell lines demonstrating up to 87 % enrichment (n = 10) with EpCAM coupled immunomagnetic beads, 73 % optical detection and dispensing efficiency (n = 5). 40 to 56.7 % of cells were recovered after complete isolation from 7.5 ml untreated whole blood (n = 6). In this study, CTCelect enabled automated dispensing of single circulating tumor cells from HNSCC patient samples, qPCR‐based confirmation of tumor‐related biomarkers and immunostaining. Finally, the platform was compared to commercial CTC isolation technologies to highlight advantages and limitations of CTCelect. This system offers new possibilities for single cell screening in cancer diagnostics, individual therapy approaches and real‐time monitoring.

Differential early diagnosis of benign versus malignant lung cancer using systematic pathway flux analysis of peripheral blood leukocytes

Early diagnosis of lung cancer is critically important to reduce disease severity and improve overall survival. Newer, minimally invasive biopsy procedures often fail to provide adequate specimens for accurate tumor subtyping or staging which is necessary to inform appropriate use of molecular targeted therapies and immune checkpoint inhibitors. Thus newer approaches to diagnosis and staging in early lung cancer are needed. This exploratory pilot study obtained peripheral blood samples from 139 individuals with clinically evident pulmonary nodules (benign and malignant), as well as ten healthy persons. They were divided into three cohorts: original cohort (n = 99), control cohort (n = 10), and validation cohort (n = 40). Average RNAseq sequencing of leukocytes in these samples were conducted. Subsequently, data was integrated into artificial intelligence (AI)-based computational approach with system-wide gene expression technology to develop a rapid, effective, non-invasive immune index for early diagnosis of lung cancer. An immune-related index system, IM-Index, was defined and validated for the diagnostic application. IM-Index was applied to assess the malignancies of pulmonary nodules of 109 participants (original + control cohorts) with high accuracy (AUC: 0.822 [95% CI: 0.75-0.91, p < 0.001]), and to differentiate between phases of cancer immunoediting concept (odds ratio: 1.17 [95% CI: 1.1-1.25, p < 0.001]). The predictive ability of IM-Index was validated in a validation cohort with a AUC: 0.883 (95% CI: 0.73-1.00, p < 0.001). The difference between molecular mechanisms of adenocarcinoma and squamous carcinoma histology was also determined via the IM-Index (OR: 1.2 [95% CI 1.14-1.35, p = 0.019]). In addition, a structural metabolic behavior pattern and signaling property in host immunity were found (bonferroni correction, p = 1.32e - 16). Taken together our findings indicate that this AI-based approach may be used for "Super Early" cancer diagnosis and amend the current immunotherpay for lung cancer.

The Impact of the Animal Housing System on Immune Cell Composition and Function in the Blood of Dromedary Camels

Simple Summary

The present study investigated the impacts of a change in animal housing system on selected parameters of the camel immune system. Samples collected from camels during a free-ranging time were compared with samples collected from the same camels during movement-restricted housing. Movement-restricted camels showed elevated myeloperoxidase activity in their serum, a significant shape-change of their neutrophils, and higher reactive oxygen species content in their monocytes and neutrophils. The leukogram pattern of the camels under restricted housing was characterized by increased numbers of neutrophils, eosinophils, lymphocytes, and monocytes. Within the lymphocyte population, only the helper T cells and B cells were expanded in animals under restricted housing. In addition, restricted housing modulated the expression of several cell surface antigens, including monocyte-polarization markers and cell adhesion molecules. Functional analysis of bacterial phagocytosis indicated impaired antibacterial function of phagocytes in camels under restricted housing. In summary, the present study identified significant changes in blood immune cell composition, phenotype, and function in dromedary camels under restricted-housing conditions, and suggests the development of an excitement leukogram in those animals.

Abstract

Background: The dromedary camel (Camelus dromedarius) is an important livestock animal of desert and semi-desert ecosystems. In recent years, several elements of the camel immune system have been characterized. Stress and excitement induced by animal housing represent the most important environmental factors with potential modulatory effects on the immune system. The present study evaluated the impacts of a restricted-housing system on some phenotypic and functional properties of blood leukocytes in dromedary camels. Methods: Immunofluorescence and flow cytometry were used to comparatively analyze samples collected from camels during a free-ranging time and samples collected from the same camels during movement-restricted housing. Results: In comparison to blood samples collected from the camels during the free-ranging time, samples from movement-restricted camels showed elevated serum myeloperoxidase activity, a significant shape-change in their neutrophils, and higher reactive oxygen species content in their monocytes and neutrophils, indicating increased cellular oxidative stress under movement-restricted housing. The leukogram pattern of the camels under restricted housing was characterized by leukocytosis with increased numbers of neutrophils, eosinophils, lymphocytes, and monocytes, resembling an excitement leukogram pattern. Within the lymphocyte population, only the helper T cells and B cells were expanded in animals under restricted housing. The upregulation of CD163 together with the downregulation of MHC-II on monocytes from excited camels indicate a modulatory potential of animal excitement to polarize monocytes toward an anti-inflammatory phenotype. Functional analysis of bacterial phagocytosis indicates an impaired antibacterial function of phagocytes in excited camels. The downregulation of several cell adhesion molecules on leukocytes from excited camels suggests a role for impaired cell adhesion and tissue migration and leukocyte retention in blood in the observed leukocytosis in animals under excitement. Conclusions: The present study identified significant changes in blood immune cell composition, phenotype, and function in dromedary camels under restricted-housing conditions. The observed changes in leukocyte composition suggest the development of an excitement leukogram pattern in camels under movement-restricted housing. To evaluate the clinical relevance of the observed changes in immune cell phenotype and function for the immune competence of camels under restricted housing, further studies are required.

Dimensions of neutrophil life and fate

The earliest reported observations on neutrophils date from 1879 to 1880, when Paul Ehrlich utilized a set of coal tar dyes to interrogate differential staining properties of the granules from white blood cells. While acidic and basic dyes identified eosinophils and basophils respectively, neutrophils were revealed by neutral dyes. Unknowingly, his work staining blood films set the stage for one of the most exciting features of immune cells discovered in the last decade, myeloid heterogeneity. Since then, advances in live imaging and high-resolution sequencing technologies have revolutionized how we analyze and envision those cells that Ehrich fixed in blood smears. Neutrophil plasticity and heterotypic interactions with immune and non-immune compartments are increasingly appreciated as an important part of their biology. In this review, we highlight early and recent work that will help the reader to appreciate our current view of the neutrophil life cycle -from maturation to elimination-, and how neutrophils behave and dynamically modulate tissue immunity, both in steady-state and in disease.

Chronic Application of Low-Dose Aspirin Affects Multiple Parameters of Three Blood Cellular Types and Antithrombin Activity: A 1:1:1 Propensity Score Matching Analysis

ABSTRACT

The mechanisms of aspirin antithrombotic actions have not been fully elucidated. We re-analyzed the data from the project Aspirin Resistance in Patients with Ischemic Atherothrombotic Diseases from April 2008 to June 2010. A total of 530 subjects were classified into 3 groups, including 40 patients without aspirin use, 24 patients taking 25-50 mg/d aspirin, and 466 patients taking 75-100 mg/d aspirin over 1 month. By 1:1:1 propensity score matching adjusting 15 primary clinical covariates, 51 patients (n = 17 per group) comprised the final sample. Hemostasis-related parameters and high platelet reactivity as measured by arachidonic acid-induced and adenosine diphosphate-induced light transmission aggregometry were compared in the 3 groups. A dose-dependent relationship was observed between aspirin and decreased high platelet reactivity incidence (PAA < 0.001, PADP < 0.01, respectively), decreased monocyte ratio (P = 0.052), increased antithrombin activity (P < 0.001), and increased platelet distribution width (P < 0.05). Aspirin at 25-50 mg/d is related to the lowest red blood cell (RBC) count, whereas 75-100 mg/d aspirin showed the highest RBC count among the 3 groups (4.52 ± 0.35 × 1012/L vs. 4.35 ± 0.57 × 1012/L vs. 4.80 ± 0.59 × 1012/L, P = 0.046). Our finding demonstrated that aspirin exerts its antithrombotic effects at least by antiplatelet function, enhancing antithrombin activity and suppressing monocytes in vivo. In addition, 3 blood cell types, namely RBCs, monocytes, and platelets, are involved in the aspirin antithrombotic mechanism. The cellular response to aspirin partially enhances the antithrombotic effects while partially inhibiting the effects.

Pre-diagnosis neutrophil-to-lymphocyte ratio and mortality in individuals who develop lung cancer

Purpose

The neutrophil-to-lymphocyte ratio (NLR) is a marker of systemic inflammation that has been reported to be associated with survival after chronic disease diagnoses, including lung cancer. We hypothesized that the inflammatory profile reflected by pre-diagnosis NLR, rather than the well-studied pre-treatment NLR at diagnosis, may be associated with increased mortality after lung cancer is diagnosed in high-risk heavy smokers.

Methods

We examined associations between pre-diagnosis methylation-derived NLR (mdNLR) and lung cancer-specific and all-cause mortality in 279 non-small lung cancer (NSCLC) and 81 small cell lung cancer (SCLC) cases from the β-Carotene and Retinol Efficacy Trial (CARET). Cox proportional hazards models were adjusted for age, sex, smoking status, pack years, and time between blood draw and diagnosis, and stratified by stage of disease. Models were run separately by histotype.

Results

Among SCLC cases, those with pre-diagnosis mdNLR in the highest quartile had 2.5-fold increased mortality compared to those in the lowest quartile. For each unit increase in pre-diagnosis mdNLR, we observed 22–23% increased mortality (SCLC-specific hazard ratio [HR] = 1.23, 95% confidence interval [CI]: 1.02, 1.48; all-cause HR = 1.22, 95% CI 1.01, 1.46). SCLC associations were strongest for current smokers at blood draw (Interaction Ps = 0.03). Increasing mdNLR was not associated with mortality among NSCLC overall, nor within adenocarcinoma (N = 148) or squamous cell carcinoma (N = 115) case groups.

Conclusion

Our findings suggest that increased mdNLR, representing a systemic inflammatory profile on average 4.5 years before a SCLC diagnosis, may be associated with mortality in heavy smokers who go on to develop SCLC but not NSCLC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10552-021-01469-3.

Açaí Reverses Adverse Cardiovascular Remodeling in Renovascular Hypertension: A Comparative Effect With Enalapril

ABSTRACT

This study aimed to determine if açai seed extract (ASE) could reverse pre-existing cardiovascular and renal injury in an experimental model of renovascular hypertension (2 kidney, 1 clip, 2K1C). Young male rats (Wistar) were used to obtain 2K1C and sham groups. Animals received the vehicle, ASE (200 mg/kg/d), or enalapril (30 mg/kg/d) in drinking water from the third to sixth week after surgery. We evaluated systolic blood pressure by tail plethysmography, vascular reactivity in the rat isolated mesenteric arterial bed (MAB), serum and urinary parameters, plasma inflammatory cytokines by ELISA, MAB expression of endothelial nitric oxide synthase and its active form peNOS by Western blot, plasma and MAB oxidative damage and antioxidant activity by spectrophotometry, and vascular and cardiac structural changes by histological analysis. ASE and enalapril reduced the systolic blood pressure, restored the endothelial and renal functions, and decreased the inflammatory cytokines and the oxidative stress in 2K1C rats. Furthermore, both treatments reduced vascular and cardiac remodeling. ASE substantially reduced cardiovascular remodeling and recovered endothelial dysfunction in 2K1C rats probably through its antihypertensive, antioxidant, and anti-inflammatory actions, supplying a natural resource for the treatment of renovascular hypertension.

Leptin Receptor q223r Polymorphism Influences Clostridioides difficile Infection-Induced Neutrophil CXCR2 Expression in an Interleukin-1β Dependent Manner

Neutrophils are key first-responders in the innate immune response to C. difficile infection (CDI) and play a central role in disease pathogenesis. Studies have clearly shown that tissue neutrophil numbers need to be tightly regulated for optimal CDI outcomes: while excessive colonic neutrophilia is associated with severe CDI, neutrophil depletion also results in worse outcomes. However, the biological mechanisms that control CDI-induced neutrophilia remain poorly defined. C-X-C chemokine receptor 2 (CXCR2) is a chemotactic receptor that is critical in neutrophil mobilization from bone marrow to blood and tissue sites. We have previously reported that a single nucleotide polymorphism (SNP) in leptin receptor (LEPR), present in up to 50% of people, influenced CDI-induced neutrophil CXCR2 expression and tissue neutrophilia. Homozygosity for mutant LEPR (i.e. RR genotype) was associated with higher CXCR2 expression and more tissue neutrophils. Here, we investigated the biological mechanisms that regulate neutrophil CXCR2 expression after CDI, and the influence of host genetics on this process. Our data reveal that: a) CXCR2 plays a key role in CDI-induced neutrophil extravasation from blood to colonic tissue; b) plasma from C. difficile-infected mice upregulated CXCR2 on bone marrow neutrophils; c) plasma from C. difficile-infected RR mice induced a higher magnitude of CXCR2 upregulation and had more IL-1β; and d) IL-1β neutralization reduced CXCR2 expression on bone marrow and blood neutrophils and their subsequent accrual to colonic tissue. In sum, our data indicate that IL-1β is a key molecular mediator that communicates between gastro-intestinal tract (i.e. site of CDI) and bone marrow (i.e. primary neutrophil reservoir) and regulates the intensity of CDI-induced tissue neutrophilia by modulating CXCR2 expression. Further, our studies highlight the importance of host genetics in affecting these innate immune responses and provide novel insights into the mechanisms by which a common SNP influences CDI-induced neutrophilia.

The Role of Oxidative Stress in Cardiovascular Aging and Cardiovascular Diseases

Aging can be seen as process characterized by accumulation of oxidative stress induced damage. Oxidative stress derives from different endogenous and exogenous processes, all of which ultimately lead to progressive loss in tissue and organ structure and functions. The oxidative stress theory of aging expresses itself in age-related diseases. Aging is in fact a primary risk factor for many diseases and in particular for cardiovascular diseases and its derived morbidity and mortality. Here we highlight the role of oxidative stress in age-related cardiovascular aging and diseases. We take into consideration the molecular mechanisms, the structural and functional alterations, and the diseases accompanied to the cardiovascular aging process.

Neurobiology of resilience in depression: immune and vascular insights from human and animal studies

Major depressive disorder (MDD) is a chronic and recurrent psychiatric condition characterized by depressed mood, social isolation and anhedonia. It will affect 20% of individuals with considerable economic impacts. Unfortunately, 30-50% of depressed individuals are resistant to current antidepressant treatments. MDD is twice as prevalent in women and associated symptoms are different. Depression's main environmental risk factor is chronic stress, and women report higher levels of stress in daily life. However, not every stressed individual becomes depressed, highlighting the need to identify biological determinants of stress vulnerability but also resilience. Based on a reverse translational approach, rodent models of depression were developed to study the mechanisms underlying susceptibility vs resilience. Indeed, a subpopulation of animals can display coping mechanisms and a set of biological alterations leading to stress resilience. The aetiology of MDD is multifactorial and involves several physiological systems. Exacerbation of endocrine and immune responses from both innate and adaptive systems are observed in depressed individuals and mice exhibiting depression-like behaviours. Increasing attention has been given to neurovascular health since higher prevalence of cardiovascular diseases is found in MDD patients and inflammatory conditions are associated with depression, treatment resistance and relapse. Here, we provide an overview of endocrine, immune and vascular changes associated with stress vulnerability vs. resilience in rodents and when available, in humans. Lack of treatment efficacy suggests that neuron-centric treatments do not address important causal biological factors and better understanding of stress-induced adaptations, including sex differences, could contribute to develop novel therapeutic strategies including personalized medicine approaches.

The gut microbiota is associated with immune cell dynamics in humans

The gut microbiota influences development1-3 and homeostasis4-7 of the mammalian immune system, and is associated with human inflammatory8 and immune diseases9,10 as well as responses to immunotherapy11-14. Nevertheless, our understanding of how gut bacteria modulate the immune system remains limited, particularly in humans, where the difficulty of direct experimentation makes inference challenging. Here we study hundreds of hospitalized-and closely monitored-patients with cancer receiving haematopoietic cell transplantation as they recover from chemotherapy and stem-cell engraftment. This aggressive treatment causes large shifts in both circulatory immune cell and microbiota populations, enabling the relationships between the two to be studied simultaneously. Analysis of observed daily changes in circulating neutrophil, lymphocyte and monocyte counts and more than 10,000 longitudinal microbiota samples revealed consistent associations between gut bacteria and immune cell dynamics. High-resolution clinical metadata and Bayesian inference allowed us to compare the effects of bacterial genera in relation to those of immunomodulatory medications, revealing a considerable influence of the gut microbiota-together and over time-on systemic immune cell dynamics. Our analysis establishes and quantifies the link between the gut microbiota and the human immune system, with implications for microbiota-driven modulation of immunity.

Proliferation: Driver of HSC aging phenotypes?

The decline of stem cell performance with age is a potential paramount mechanism of aging. Hematopoietic stem cells (HSCs) are perhaps the most studied and best characterized tissue-specific somatic stem cells. As such, HSCs offer an excellent research model of how aging affects stem cell performance, and vice versa. Studies from recent years have elucidated major aging phenotypes of HSCs including a decline in reconstitution potential, altered differentiation predisposition, an increase in number, accumulation of DNA damage/mutations and several others. However, what drives these changes, and exactly how they translate to pathology is poorly understood. Recent studies point to proliferative stress of HSCs as a potential driver of their aging and the resulting pathologies. Here we discuss the recent discoveries and suggest the context in which aging phenotypes could be driven, and the relevant mechanisms by which HSCs could be affected.

Leukocyte populations in peripheral blood of dromedary camels with clinical endometritis

Endometritis represents the main cause of reproductive failure in dromedary camels. In dromedary camels, associations between endometritis-causing pathogen-species, disease severity, and systemic changes in the immune system have not been evaluated. In the current study, there was use of flow cytometry and immunofluorescence of membrane proteins for the evaluation of leukocyte subsets and the cellular phenotype in blood of camels with clinical endometritis and evaluations of associations with disease severity and endometritis-causing pathogens. Animals with endometritis had markedly larger numbers of total leukocytes and neutrophils. Although total lymphocyte and monocyte counts did not differ between camels with and without clinical endometritis, there were lesser numbers of total and effector CD4-positive T cells in camels with endometritis. Among monocytes, number of camel inflammatory monocytes (Mo-II) was markedly greater, whereas Mo-III numbers were less in the blood of camels with clinical endometritis. Number of inflammatory monocytes was also indicative of endometritis severity grade. Among camels with clinical endometritis, E. coli- and S. aureus-infected animals had similar endometritis grades and comparable phenotype and composition patterns of leukocytes. Neutrophils and monocytes of camels with clinical endometritis had fewer cell adhesion molecules (i.e., CD11a and CD18). Collectively, the results from the current study allowed for identification of associations between endometritis severity grade and larger numbers of inflammatory monocytes. The results also indicate there is no association between endometritis pathogen-species and changes in phenotype or composition of blood leukocytes.

Leukocyte populations and their cell adhesion molecules expression in newborn dromedary camel calves

Background and Aim

Different properties of the newborn immune system have been characterized in many species. For the newborn camel calf, however, the phenotype and composition of blood leukocytes have so far not been evaluated. The current study aimed to analyze the distribution of leukocyte subpopulations and their expression pattern of cell adhesion molecules in newborn and adult dromedary camels.

Materials and Methods

Blood samples were collected from 17 newborn camel calves and 32 adult camels. For each sample, total leukocytes were separated and analyzed for their composition and cell adhesion molecules expression by flow cytometry.

Results

In comparison to adult camels, newborn camel calves had higher leukocyte numbers and higher numbers of neutrophils, monocytes, and lymphocytes but lower numbers of eosinophils in their blood. Among the lymphocyte populations in calves, the fractions of B cells and γ^δ T cells were elevated when compared to adults, whereas CD4-positive T cells were reduced. The comparison between camel calves and adult camels revealed significantly lower expression of the cell adhesion molecules CD11a, CD11b, and CD18 on granulocytes, monocytes, and lymphocytes in calves.

Conclusion

Newborn camel calves show a distinct composition and phenotype pattern of blood leukocytes when compared to adult camels. The observed rise in many leukocyte populations in calf blood may be due to reduced migratory activity in calf leukocyte populations.

Structural and functional diversity of neutrophil glycosylation in innate immunity and related disorders

The granulated neutrophils are abundant innate immune cells that utilize bioactive glycoproteins packed in cytosolic granules to fight pathogenic infections, but the neutrophil glycobiology remains poorly understood. Facilitated by technological advances in glycoimmunology, systems glycobiology and glycoanalytics, a considerable body of literature reporting on novel aspects of neutrophil glycosylation has accumulated. Herein, we summarize the building knowledge of the structural and functional diversity displayed by N- and O-linked glycoproteins spatiotemporally expressed and sequentially brought-into-action across the diverse neutrophil life stages during bone marrow maturation, movements to, from and within the blood circulation and microbicidal processes at the inflammatory sites in peripheral tissues. It transpires that neutrophils abundantly decorate their granule glycoproteins including neutrophil elastase, myeloperoxidase and cathepsin G with peculiar glyco-signatures not commonly reported in other areas of human glycobiology such as hyper-truncated chitobiose core- and paucimannosidic-type N-glycans and monoantennary complex-type N-glycans. Sialyl Lewis^x, Lewis^x, poly-N-acetyllactosamine extensions and core 1-/2-type O-glycans are also common neutrophil glyco-signatures. Granule-specific glycosylation is another fascinating yet not fully understood feature of neutrophils. Recent literature suggests that unconventional biosynthetic pathways and functions underpin these prominent neutrophil-associated glyco-phenotypes. The impact of glycosylation on key neutrophil effector functions including extravasation, degranulation, phagocytosis and formation of neutrophil extracellular traps during normal physiological conditions and in innate immune-related diseases is discussed. We also highlight new technologies that are expected to further advance neutrophil glycobiology and briefly discuss the untapped diagnostic and therapeutic potential of neutrophil glycosylation that could open avenues to combat the increasingly prevalent innate immune disorders.

Population Pharmacodynamic Model of Neutrophil Margination and Tolerance to Describe Effect of Sarilumab on Absolute Neutrophil Count in Patients with Rheumatoid Arthritis

Evidence suggests that effects of interleukin‐6 pathway inhibitors sarilumab, tocilizumab, and sirukumab on absolute neutrophil count (ANC) are due to margination of circulating neutrophils into rapidly mobilizable noncirculating pools. We developed a population pharmacodynamic model using compartments for neutrophil margination and ANC‐specific tolerance to describe rapid, transient ANC changes in blood following administration of subcutaneous sarilumab and intravenous/subcutaneous tocilizumab based on data from 322 patients with rheumatoid arthritis in two single‐dose (NCT02097524 and NCT02404558) and one multiple‐dose (NCT01768572) trials. The model incorporated a tolerance compartment to account for ANC nadir and beginning of recovery before maximal drug concentration after subcutaneous dosing, and absence of a nadir plateau when the ANC response is saturated after subcutaneous or intravenous dosing. The model effectively describes the ANC changes and supports neutrophil margination and tolerance as an explanation for the absence of increased infection risk associated with low ANC due to interleukin‐6 pathway inhibitor treatment.

Modifiable Cardiovascular Risk, Hematopoiesis, and Innate Immunity

Unhealthy diet, lack of exercise, psychosocial stress, and insufficient sleep are increasingly prevalent modifiable risk factors for cardiovascular disease. Accumulating evidence indicates that these risk factors may fuel chronic inflammatory processes that are active in atherosclerosis and lead to myocardial infarction and stroke. In concert with hyperlipidemia, maladaptive immune system activities can contribute to disease progression and increase the probability of adverse events. In this review, we discuss recent insight into how the above modifiable risk factors influence innate immunity. Specifically, we focus on pathways that raise systemic myeloid cell numbers and modulate immune cell phenotypes, reviewing hematopoiesis, leukocyte trafficking, and innate immune cell accumulation in cardiovascular organs. Often, relevant mechanisms that begin with lifestyle choices and lead to cardiovascular events span multiple organ systems, including the central nervous, endocrine, metabolic, hematopoietic, immune and, finally, the cardiovascular system. We argue that deciphering such pathways provides not only support for preventive interventions but also opportunities to develop biomimetic immunomodulatory therapeutics that mitigate cardiovascular inflammation.

The haematopoietic stem cell niche: a new player in cardiovascular disease?

Haematopoiesis, the process of blood production, can be altered during the initiation or progression of many diseases. Cardiovascular disease (CVD) has been shown to be heavily influenced by changes to the haematopoietic system, including the types and abundance of immune cells produced. It is now well established that innate immune cells are increased in people with CVD, and the mechanisms contributing to this can be vastly different depending on the risk factors or comorbidities present. Many of these changes begin at the level of the haematopoietic stem and progenitor cells (HSPCs) that reside in the bone marrow (BM). In general, the HSPCs and downstream myeloid progenitors are expanded via increased proliferation in the setting of atherosclerotic CVD. However, HSPCs can also be encouraged to leave the BM and colonise extramedullary sites (i.e. the spleen). Within the BM, HSPCs reside in specialized microenvironments, often referred to as a niche. To date in depth studies assessing the damage or dysregulation that occurs in the BM niche in varying CVDs are scarce. In this review, we provide a general overview of the complex components and interactions within the BM niche and how they influence the function of HSPCs. Additionally, we discuss the main findings regarding changes in the HSPC niche that influence the progression of CVD. We hypothesize that understanding the influence of the BM niche in CVD will aid in delineating new pathways for therapeutic interventions.

Where Is Dopamine and how do Immune Cells See it?: Dopamine-Mediated Immune Cell Function in Health and Disease

Dopamine is well recognized as a neurotransmitter in the brain, and regulates critical functions in a variety of peripheral systems. Growing research has also shown that dopamine acts as an important regulator of immune function. Many immune cells express dopamine receptors and other dopamine related proteins, enabling them to actively respond to dopamine and suggesting that dopaminergic immunoregulation is an important part of proper immune function. A detailed understanding of the physiological concentrations of dopamine in specific regions of the human body, particularly in peripheral systems, is critical to the development of hypotheses and experiments examining the effects of physiologically relevant dopamine concentrations on immune cells. Unfortunately, the dopamine concentrations to which these immune cells would be exposed in different anatomical regions are not clear. To address this issue, this comprehensive review details the current information regarding concentrations of dopamine found in both the central nervous system and in many regions of the periphery. In addition, we discuss the immune cells present in each region, and how these could interact with dopamine in each compartment described. Finally, the review briefly addresses how changes in these dopamine concentrations could influence immune cell dysfunction in several disease states including Parkinson's disease, multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease, as well as the collection of pathologies, cognitive and motor symptoms associated with HIV infection in the central nervous system, known as NeuroHIV. These data will improve our understanding of the interactions between the dopaminergic and immune systems during both homeostatic function and in disease, clarify the effects of existing dopaminergic drugs and promote the creation of new therapeutic strategies based on manipulating immune function through dopaminergic signaling. Graphical Abstract.

Heterogeneity of neutrophils

Structured models of ontogenic, phenotypic and functional diversity have been instrumental for a renewed understanding of the biology of immune cells, such as macrophages and lymphoid cells. However, there are no established models that can be used to define the diversity of neutrophils, the most abundant myeloid cells. This lack of an established model is largely due to the uniquely short lives of neutrophils, a consequence of their inability to divide once terminally differentiated, which has been perceived as a roadblock to functional diversity. This perception is rapidly evolving as multiple phenotypic and functional variants of neutrophils have been found, both in homeostatic and disease conditions. In this Opinion article, we present an overview of neutrophil heterogeneity and discuss possible mechanisms of diversification, including genomic regulation. We suggest that neutrophil heterogeneity is an important feature of immune pathophysiology, such that co-option of the mechanisms of diversification by cancer or other disorders contributes to disease progression.

Relation between carotid vulnerable plaques and peripheral leukocyte: a case-control study of comparison utilizing multi-parametric contrast-enhanced ultrasound

Background

This study evaluates carotid vulnerable plaques using contrast-enhanced ultrasound (CEUS) and explores the relationship between vulnerable plaques and leukocytes.

Methods

Sixty-two symptomatic and 54 asymptomatic patients underwent CEUS. The images were analyzed using time-intensity and fitting curves, and peak (P_TIC), mean (M_TIC), peak (P_FC), sharpness (S_FC), and area under the curve (AUC_FC) were obtained. The relations between CEUS parameters and leukocytes were analyzed.

Results

In the symptomatic group, total leukocytes and neutrophils were higher, while lymphocyte was decreased; P_TIC, M_TIC, P_FC, S_FC, and AUC_FC were significantly higher; M_TIC and AUC_FC were negatively correlated with lymphocytes, and M_TIC was positively correlated with neutrophils. Classification and regression tree analysis showed that M_TIC at a cutoff of 20.8 and AUC_FC at a cutoff of 8.8 resulted in a predictive of acute cerebral infarction, accuracy of 84.3%, sensitivity of 87.1%, and specificity of 81.5%.

Conclusions

The variation in the perivascular leucocyte is significantly related to intraplaque inflammatory activities, CEUS is a feasible monitor of intraplaque neovascularization, so CEUS combined with perivascular leucocyte could be helpful as a warning for vulnerable plaques.

The liver as a nursery for leukocytes

Leukocytes are a large population of cells spread within most tissues in the body. These cells may be either sessile (called as resident cells) or circulating leukocytes, which travel long journeys inside the vessels during their lifespan. Although production and maturation of these leukocytes in adults primarily occur in the bone marrow, it is well known that this process-called hematopoiesis-started in the embryonic life in different sites, including the yolk sac, placenta, and the liver. In this review, we will discuss how the liver acts as a pivotal site for leukocyte maturation during the embryo phase, and also how the most frequent liver-resident immune cell populations-namely Kupffer cells, dendritic cells, and lymphocytes-play a vital role in both tolerance and inflammatory responses to antigens from food, microbiota, and pathogens.

Neutrophils as regulators of the hematopoietic niche

The niche that supports hematopoietic stem and progenitor cells (HSPCs) in the bone marrow is a highly dynamic structure. It maintains core properties of HSPCs in the steady state, and modulates their proliferation and differentiation in response to changing physiological demands or pathological insults. The dynamic and environment-sensing properties of the niche are shared by the innate immune system. Thus, it is not surprising that innate immune cells, including macrophages and neutrophils, are now recognized as important regulators of the hematopoietic niche and, ultimately, of the stem cells from which they derive. This review synthesizes emerging concepts on niche regulation by immune cells, with a particular emphasis on neutrophils. We argue that the unique developmental, circadian, and migratory properties of neutrophils underlie their critical contributions as regulators of the hematopoietic niche.

A Subset of Type I Conventional Dendritic Cells Controls Cutaneous Bacterial Infections through VEGFα-Mediated Recruitment of Neutrophils

Skin conventional dendritic cells (cDCs) exist as two distinct subsets, cDC1s and cDC2s, which maintain the balance of immunity to pathogens and tolerance to self and microbiota. Here, we examined the roles of dermal cDC1s and cDC2s during bacterial infection, notably Propionibacterium acnes (P. acnes). cDC1s, but not cDC2s, regulated the magnitude of the immune response to P. acnes in the murine dermis by controlling neutrophil recruitment to the inflamed site and survival and function therein. Single-cell mRNA sequencing revealed that this regulation relied on secretion of the cytokine vascular endothelial growth factor α (VEGF-α) by a minor subset of activated EpCAM+CD59+Ly-6D+ cDC1s. Neutrophil recruitment by dermal cDC1s was also observed during S. aureus, bacillus Calmette-Guérin (BCG), or E. coli infection, as well as in a model of bacterial insult in human skin. Thus, skin cDC1s are essential regulators of the innate response in cutaneous immunity and have roles beyond classical antigen presentation.

Toxicity Evaluation of Anacardium occidentale, the Potential Aphrodisiac Herb

Anacardium occidentale L. leaf demonstrates sexual enhancement effect. Therefore, it can be used as the potential supplement and functional ingredient. However, the ethanolic leaf extract of this plant is a modified form of traditional application and the toxicity evaluation is required. To assess cytotoxicity of the extract, RAW 264.7 cells were treated with A. occidentale leaf extract in the concentration range between 0.625 and 10 mg/mL. Our results showed that the extract showed more than 90% cell viability at the concentration of 2.5 mg/mL after 24-hour exposure. To assure the consumption safety, the acute and subchronic toxicity must be studied. Acute toxicity showed that the extract is safe even at the highest dose of 2 g/kg in both sexes of Wistar rats. No changes in behavior, physiology, gross pathology, and histology were observed. To determine the subchronic toxicity of extract, both sexes of Wistar rats were orally given the extract at doses of 20, 100, and 500 mg/kg once daily for 90 days. No changes in body weight, food, and water intake, motor coordination, behavior, and mental alertness were observed. The significant reduction of white blood cell, platelet, and cholesterol together with increase in MCHC was observed in male rats. The reductions of white blood cell and platelet together with the elevations of hemoglobin and hematocrit were also observed in female rats. However, all changes were in normal range. The current results revealed that an ethanolic extract of A. occidentale leaf was well tolerated via oral consumption up to dose of 500 mg/kg BW for 90 days and did not produce any toxicity. Our in vitro cytotoxicity test also confirmed this safety.

The Gp1ba-Cre transgenic mouse: a new model to delineate platelet and leukocyte functions

Conditional knockout (KO) mouse models are invaluable for elucidating the physiological roles of platelets. The Platelet factor 4-Cre recombinase (Pf4-Cre) transgenic mouse is the current model of choice for generating megakaryocyte/platelet-specific KO mice. Platelets and leukocytes work closely together in a wide range of disease settings, yet the specific contribution of platelets to these processes remains unclear. This is partially a result of the Pf4-Cre transgene being expressed in a variety of leukocyte populations. To overcome this issue, we developed a Gp1ba-Cre transgenic mouse strain in which Cre expression is driven by the endogenous Gp1ba locus. By crossing Gp1ba-Cre and Pf4-Cre mice to the mT/mG dual-fluorescence reporter mouse and performing a head-to-head comparison, we demonstrate more stringent megakaryocyte lineage-specific expression of the Gp1ba-Cre transgene. Broader tissue expression was observed with the Pf4-Cre transgene, leading to recombination in many hematopoietic lineages, including monocytes, macrophages, granulocytes, and dendritic and B and T cells. Direct comparison of phenotypes of Csk, Shp1, or CD148 conditional KO mice generated using either the Gp1ba-Cre or Pf4-Cre strains revealed similar platelet phenotypes. However, additional inflammatory and immunological anomalies were observed in Pf4-Cre-generated KO mice as a result of nonspecific deletion in other hematopoietic lineages. By excluding leukocyte contributions to phenotypes, the Gp1ba-Cre mouse will advance our understanding of the role of platelets in inflammation and other pathophysiological processes in which platelet-leukocyte interactions are involved.

Effects of mobile phone exposure on biochemical parameters of cord blood: A preliminary study

The purpose of this study is to investigate foetal impact of radiofrequencies (RFs) emitted from mobile phones in postnatal cord blood. The study carried on 149 pregnant women divided into four groups such as nonusers of mobile phone (n: 37; control group), 2-15 min/d (n: 39; group 1), 15-60 min/d (n: 37; group 2) and participants using mobile phone for more than 60 min/d (n: 36; group 3). Cord blood of the infants was taken in all groups for biochemical analyses immediately after birth. The results of the study showed that the biggest foetal impact was observed in the third study group which was pregnant exposed RFRs (RF radiation) more than 1 h/d (1 hour per day). AST (aspartat aminotransferaz), ALT (alanine aminotransferase), LDH (lactate dehydrogenase), CK (creatine kinase), CK-MB (creatine kinase-miyocardial band), CRP (c-reactive protein), PCT (procalcitonin), TnT (troponin T), uric acid and lactate levels of third group were found higher than the other groups (p < 0.001). However, Mean platelet volume values of third group were found lower than the other groups (p < 0.001). Finally, this is the first human study which was performed on pregnant and infants because there is no previous work in this area. However, the results of this study revealed that long-term RFR exposure of pregnant may result in some biochemical changes in the infants. Therefore, our suggestion to pregnant is to avoid from RFR exposure emitted from mobile phones at least during pregnancy.

Epigenetics and Immunometabolism in Diabetes and Aging

SIGNIFICANCE

A strong relationship between hyperglycemia, impaired insulin pathway, and cardiovascular disease in type 2 diabetes (T2D) is linked to oxidative stress and inflammation. Immunometabolic pathways link these pathogenic processes and pose important potential therapeutic targets. Recent Advances: The link between immunity and metabolism is bidirectional and includes the role of inflammation in the pathogenesis of metabolic disorders such as T2D, obesity, metabolic syndrome, and hypertension and the role of metabolic factors in regulation of immune cell functions. Low-grade inflammation, oxidative stress, balance between superoxide and nitric oxide, and the infiltration of macrophages, T cells, and B cells in insulin-sensitive tissues lead to metabolic impairment and accelerated aging.

CRITICAL ISSUES

Inflammatory infiltrate and altered immune cell phenotype precede development of metabolic disorders. Inflammatory changes are tightly linked to alterations in metabolic status and energy expenditure and are controlled by epigenetic mechanisms.

FUTURE DIRECTIONS

A better comprehension of these mechanistic insights is of utmost importance to identify novel molecular targets. In this study, we describe a complex scenario of epigenetic changes and immunometabolism linking to diabetes and aging-associated vascular disease. Antioxid. Redox Signal. 29, 257-274.

The role of infiltrating immune cells in dysfunctional adipose tissue

Adipose tissue (AT) dysfunction, characterized by loss of its homeostatic functions, is a hallmark of non-communicable diseases. It is characterized by chronic low-grade inflammation and is observed in obesity, metabolic disorders such as insulin resistance and diabetes. While classically it has been identified by increased cytokine or chemokine expression, such as increased MCP-1, RANTES, IL-6, interferon (IFN) gamma or TNFα, mechanistically, immune cell infiltration is a prominent feature of the dysfunctional AT. These immune cells include M1 and M2 macrophages, effector and memory T cells, IL-10 producing FoxP3+ T regulatory cells, natural killer and NKT cells and granulocytes. Immune composition varies, depending on the stage and the type of pathology. Infiltrating immune cells not only produce cytokines but also metalloproteinases, reactive oxygen species, and chemokines that participate in tissue remodelling, cell signalling, and regulation of immunity. The presence of inflammatory cells in AT affects adjacent tissues and organs. In blood vessels, perivascular AT inflammation leads to vascular remodelling, superoxide production, endothelial dysfunction with loss of nitric oxide (NO) bioavailability, contributing to vascular disease, atherosclerosis, and plaque instability. Dysfunctional AT also releases adipokines such as leptin, resistin, and visfatin that promote metabolic dysfunction, alter systemic homeostasis, sympathetic outflow, glucose handling, and insulin sensitivity. Anti-inflammatory and protective adiponectin is reduced. AT may also serve as an important reservoir and possible site of activation in autoimmune-mediated and inflammatory diseases. Thus, reciprocal regulation between immune cell infiltration and AT dysfunction is a promising future therapeutic target.

Endothelial cell-cell adhesion and signaling

Endothelial cells line blood vessels and provide a dynamic interface between the blood and tissues. They remodel to allow leukocytes, fluid and small molecules to enter tissues during inflammation and infections. Here we compare the signaling networks that contribute to endothelial permeability and leukocyte transendothelial migration, focusing particularly on signals mediated by small GTPases that regulate cell adhesion and the actin cytoskeleton. Rho and Rap GTPase signaling is important for both processes, but they differ in that signals are activated locally under leukocytes, whereas endothelial permeability is a wider event that affects the whole cell. Some molecules play a unique role in one of the two processes, and could therefore be targeted to selectively alter either endothelial permeability or leukocyte transendothelial migration.

Phagocytosis imprints heterogeneity in tissue-resident macrophages

Macrophages are important for tissue function, and adapt phenotypically to each tissue by factors produced locally. A-Gonzalez et al. now show that phagocytosis of unwanted cells additionally contributes to imprinting macrophage heterogeneity, thus promoting tissue homeostasis.

Tissue-resident macrophages display varying phenotypic and functional properties that are largely specified by their local environment. One of these functions, phagocytosis, mediates the natural disposal of billions of cells, but its mechanisms and consequences within living tissues are poorly defined. Using a parabiosis-based strategy, we identified and isolated macrophages from multiple tissues as they phagocytosed blood-borne cellular material. Phagocytosis was circadianally regulated and mediated by distinct repertoires of receptors, opsonins, and transcription factors in macrophages from each tissue. Although the tissue of residence defined the core signature of macrophages, phagocytosis imprinted a distinct antiinflammatory profile. Phagocytic macrophages expressed CD206, displayed blunted expression of Il1b, and supported tissue homeostasis. Thus, phagocytosis is a source of macrophage heterogeneity that acts together with tissue-derived factors to preserve homeostasis.