Immature Neutrophils Research Articles

Effects of Exercise Therapy on Circadian Rhythm Regulation of Neutrophils

Abstract Background: Physical inactivity is recognized as a risk factor for numerous common illnesses, while exercise has been shown to be beneficial. Neutrophils are the first line of cell-mediated defense, with characterized by circadian rhythms. The liver is metabolically active organ that is strongly influenced by circadian regulation. The effects of exercise-induced circadian changes may modify the neutrophils phenotype and function. Methods: Male mice undergoing a four-week treadmill regimen for 1h at ZT3(3h after lights on). Bone marrow, blood and liver tissue were analyzed at different time points. Circadian genes and neutrophil subpopulations were assessed. Results: The circulating neutrophil numbers were fluctuated according to a circadian pattern with a peak at ZT3 and a nadir at ZT15. Rhythmicity analysis revealed that the circadian amplitude was increased, but the period and phase were unaltered. Mice subjected to exercise had fewer immature and higher mature neutrophils in bone marrow at ZT3. The expression of clock-related genes in liver, including Arntl and Clock, increased at ZT3, while others, like Per1 were decreased. The number of aged neutrophil follows diurnal patterns with a peak at ZT3, and exhibited a greater percentage and number of neutrophils with an aging phenotype in blood at Exercise group. Summary: Exercise modulates circadian-dependent neutrophils quiescence, promotes maturation of myeloid neutrophils and driven circulating neutrophil aging phenotype.

Comprehensive Review on Downconversion/Downshifting Silicate-Based Phosphors for Solar Cell Applications.

Insufficient utilization of the solar spectrum in commonly employed solar cells, stemming from a spectral mismatch between the solar spectrum and the solar cell's band gap, poses a barrier to enhancing solar cell efficiency. To overcome this challenge, downconverting silicate phosphors are employed in solar cells to capture the infrared spectrum of sunlight, thereby augmenting solar cell efficiency. Downconversion/downshifting involves in converting high-energy photons into one or two near-infrared (NIR) photons. Remarkably, silicate-based downconverting phosphors enhance solar cell sensitization, light scattering, antireflectivity, and stability. This review delves into the various energy transfer mechanisms utilized in silicate phosphors. The key aspects covered in this review encompass the development of silicate phosphors that emit NIR light and their synthesis process. The working principle of the solar cell and its parameters are discussed. The impacts of silicate phosphor size, coverage, volume concentration, and arrangement on solar cell performance are also explored. Furthermore, the study addresses several intriguing approaches for developing innovative silicate phosphors to enhance solar cell performance.

An all-inclusive model for predicting invasive bacterial infection in febrile infants age 7-60 days.

Invasive bacterial infections (IBIs) in febrile infants are rare but potentially devastating. We aimed to derive and validate a predictive model for IBI among febrile infants age 7-60 days. Data were abstracted retrospectively from electronic records of 37 emergency departments (EDs) for infants with a measured temperature >=100.4 F who underwent an ED evaluation with blood and urine cultures. Models to predict IBI were developed and validated respectively using a random 80/20 dataset split, including 10-fold cross-validation. We used precision recall curves as the classification metric. Of 4411 eligible infants with a mean age of 37 days, 29% had characteristics that would likely have excluded them from existing risk stratification protocols. There were 196 patients with IBI (4.4%), including 43 (1.0%) with bacterial meningitis. Analytic approaches varied in performance characteristics (precision recall range 0.04-0.29, area under the curve range 0.5-0.84), with the XGBoost model demonstrating the best performance (0.29, 0.84). The five most important variables were serum white blood count, maximum temperature, absolute neutrophil count, absolute band count, and age in days. A machine learning model (XGBoost) demonstrated the best performance in predicting a rare outcome among febrile infants, including those excluded from existing algorithms. Several models for the risk stratification of febrile infants have been developed. There is a need for a preferred comprehensive model free from limitations and algorithm exclusions that accurately predicts IBIs. This is the first study to derive an all-inclusive predictive model for febrile infants aged 7-60 days in a community ED sample with IBI as a primary outcome. This machine learning model demonstrates potential for clinical utility in predicting IBI.

Movement and growth of the spotted gully shark Triakis megalopterus in South African waters

The movement and growth of spotted gully sharks Triakis megalopterus (family Triakidae) along the coast of South Africa were investigated using external dart tagging. Of a total of 7 211 sharks tagged, 657 (9.1%) were recaptured over a 37-year period, from 1984 to 2021. Average distance moved by recaptured sharks was 31 (SD 82) km, with a maximum distance moved of 911 km. The longest time at liberty was 6 332 days (17.3 years). Most recaptures (66.9%) displayed resident, philopatric behaviour, although adults moved significantly more than juveniles. There was strong seasonality in the catches, with more individuals caught during summer months (October–March); however, there was no evidence to suggest that adults undertook seasonal migrations to and from mating or pupping areas. Similarly, the findings suggested that pupping likely takes place throughout their distribution and is not confined to a particular region. Growth of recaptured individuals was slow, with an average growth rate of 50 mm year−1. This was similar to the growth rate determined by vertebral band counts but suggested that individuals could reach a theoretical maximum age of 41 years. Based on the species’ resident behaviour and slow growth rate, we advocate for maintenance of the current fishing regulations and greater protection in no-take marine protected areas with suitable habitat within their distribution. Further research using acoustic telemetry is also recommended.

Multi-Omics Profiling Reveals Phenotypic and Functional Heterogeneity of Neutrophils in COVID-19.

Accumulating evidence has revealed unexpected phenotypic heterogeneity and diverse functions of neutrophils in several diseases. Coronavirus disease (COVID-19) can alter the leukocyte phenotype based on disease severity, including neutrophil activation in severe cases. However, the plasticity of neutrophil phenotypes and their relative impact on COVID-19 pathogenesis has not been well addressed. This study aimed to identify and validate the heterogeneity of neutrophils in COVID-19 and evaluate the functions of each subpopulation. We analyzed public single-cell RNA-seq, bulk RNA-seq, and proteome data from healthy donors and patients with COVID-19 to investigate neutrophil subpopulations and their response to disease pathogenesis. We identified eight neutrophil subtypes: pro-neutrophil, pre-neutrophil, immature neutrophil, and five mature neutrophil subpopulations. The subtypes exhibited distinct features, including diverse activation signatures and multiple enriched pathways. The pro-neutrophil subtype was associated with severe and fatal disease, while the pre-neutrophil subtype was particularly abundant in mild/moderate disease. One of the mature neutrophil subtypes showed consistently large fractions in patients with different disease severity. Bulk RNA-seq dataset analyses using a cellular deconvolution approach validated the relative abundances of neutrophil subtypes and the expansion of pro-neutrophils in severe COVID-19 patients. Cell-cell communication analysis revealed representative ligand-receptor interactions among the identified neutrophil subtypes. Further investigation into transcription factors and differential protein abundance revealed the regulatory network differences between healthy donors and patients with severe COVID-19. Overall, we demonstrated the complex interactions among heterogeneous neutrophil subtypes and other blood cell types during COVID-19 disease. Our work has great value in terms of both clinical and public health as it furthers our understanding of the phenotypic and functional heterogeneity of neutrophils and other cell populations in multiple diseases.

Immature neutrophils in cord blood exert increased expression of genes associated with antimicrobial function.

The immune systems of both the mother and the newborn face significant challenges during birth. Proper immune regulation after birth is essential for the survival of neonates. Numerous studies have demonstrated that the neonatal immune system is relatively immature, particularly in its adaptive arm, placing the primary responsibility for immune surveillance on innate immunity. Given the significant role of neutrophils in protecting the neonate after birth, we conducted a study investigating the properties of neutrophils in newborn cord blood using various methodological approaches. Our findings demonstrate the presence of immature low-density neutrophils in the cord blood, which are likely responsible for the observed elevated expression of genes coding for proteins essential to antimicrobial response, including myeloperoxidase, neutrophils elastase, and defensins. We propose that these cells function normally and support the protection of newborns early after birth. Furthermore, our results suggest that the mode of delivery might significantly influence the programming of neutrophil function. The presented findings emphasize the importance of distinct neutrophil subpopulations in neonatal immunity and their potential impact on early postnatal health.

Abstract 3917: A CXCR4 partial agonist TFF2-MSA improves anti-PD-1 immunotherapy in advanced gastric cancer by selectively targeting PMN-MDSC

Abstract Introduction: Advanced gastric cancer poses a challenge for PD-1 immunotherapy due in part to the prevalence of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs). PMN-MDSCs are mostly immature granulocytes but coexist with mature neutrophils, complicating their precise targeting. While PMN-MDSCs highly express CXCR4, recent clinical trials suggest that CXCR4 antagonists may provide limited additive efficacy to PD-1 blockade. This study explored the efficacy of a secreted CXCR4 partial agonist, trefoil factor family 2 (TFF2), in the context of anti-PD-1 refractory gastric cancer. Methods: We fused mouse TFF2 with murine serum albumin to generate a novel TFF2-MSA peptide with extended half-life, and evaluated its therapeutic effects with or without anti-PD-1 antibody. As histidine decarboxylase (HDC) is expressed in immature neutrophils, we used the HDC-GFP transgene to track PMN-MDSC in vivo. The HDC-GFP mice received subcutaneous or orthotopic implantation of murine syngeneic gastric cancer cells and subsequent treatments. Additionally, human blood was assessed for both serum TFF2 and immune profiles. Results: The combination of TFF2-MSA plus anti-PD-1 antibody displayed remarkable synergy, boosting intratumoral cytotoxic CD8 T cells by 50-fold, leading to tumor regression or eradication, 80% reduction of distant metastasis and 2-fold extension of mouse survival. The immunosuppressive HDC-GFP+ PMN-MDSCs expressed the highest level of CXCR4 among immune cells, and TFF2-MSA treatment systematically reduced HDC-GFP+ PMN-MDSCs in the tumor, blood, spleen and their myeloid progenitors in the bone marrow. In contrast, CXCR4 antagonist AMD3100 in combination with anti-PD-1 failed to restrict tumor growth or PMN-MDSCs. Further single-cell RNA-seq and functional assays revealed that combination of TFF2-MSA plus anti-PD-1 induced a skewing of remaining tumor HDC-GFP+PMN-MDSC compositions from highly immature CD300ld+ subsets to less immature subsets expressing interferon-stimulated genes, accompanied by reduced immunosuppression and increased antigen presentation functions. Rather than local reprogramming, this compositional shift stemmed from an IRF1-driven interferon response in splenic HDC-GFP+ PMN-MDSCs. In human, PMN-MDSCs marked by LOX1 significantly expanded in the blood of gastric cancer patients compared to healthy donors. Human LOX1+ PMN-MDSCs showed an inverse correlation with T cell number, activation, proliferation and the serum TFF2 level. Conclusions: TFF2-MSA synergizes with PD-1 blockade by selectively targeting CXCR4high PMN-MDSCs. This study provides a rational for a novel combination therapy of the CXCR4 partial agonist, TFF2-MSA, rather than CXCR4 antagonists, plus PD-1 blockade for treatment of advanced gastric cancer. Citation Format: Jin Qian, Chenkai Ma, Quin T. Waterbury, Christine S. Moon, Xiaofei Zhi, Feijing Wu, Ruhong Tu, Biyun Zheng, Hiroki Kobayashi, Leah B. Zamechek, Ryan H. Moy, Arnold Han, Bruce Daugherty, Seth Lederman, Timothy C. Wang. A CXCR4 partial agonist TFF2-MSA improves anti-PD-1 immunotherapy in advanced gastric cancer by selectively targeting PMN-MDSC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3917.

Abstract 5463: Germline DICER1 loss promotes rhabdomyosarcoma via innate immune system

Abstract DICER1 syndrome is a cancer predisposition syndrome where affected patients have increased risk of neoplasms including pleuropulmonary blastoma, Sertoli-Leydig cell tumor, and fusion-negative rhabdomyosarcoma (FN-RMS). This syndrome is defined by germline heterozygous loss of function mutations in the gene DICER1, but it remains unclear exactly how these mutations predispose children to develop cancer. One would expect the germline loss of one allele to provide a sensitized background in the tumor cell to acquire a second hit mutation. To gain insight into the role of Dicer1 loss in FN-RMS, we deleted the Dicer1 gene both globally in the germline and conditionally in the tumor cell in our previously established mouse model of FN-RMS. Surprisingly, we observed faster tumor onset and increased penetrance in mice with germline heterozygous Dicer1 loss (Dicer1+/-) but not in mice where Dicer1 loss was restricted to the tumor cells, demonstrating that Dicer1 functions as a non-cell autonomous haploinsufficient tumor suppressor. Single cell RNA sequencing (scRNA-Seq) revealed massive expansion of immature neutrophils in Dicer1+/- tumors, which were enriched for proteases associated with neutrophil extracellular traps (NETs). NETs are webs of chromatin and proteases released when neutrophils undergo NETosis in response to inflammatory stimuli. These NETs are known to cause significant damage to the local extracellular matrix (ECM) and have been implicated in tumor promotion. In addition to the neutrophil enriched immunophenotype, we found that Dicer1+/- tumors show significant ECM remodeling and are enriched for C5a, the potent neutrophil chemoattractant and NET-priming factor. Taken together, these results suggest NETosis is upregulated in Dicer1+/- FN-RMS tumors. Performing iTALK ligand-receptor pair analysis on the scRNA-Seq data revealed a putative interaction between a NET-derived ligand and EGFR and IGF1R on tumor cells, suggesting direct tumor promoting signaling from NET-to-tumor. We validated this novel FN-RMS promotion mechanism in vitro using human FN-RMS cell lines and observed that this NET-derived ligand promoted FN-RMS growth in a dose-dependent manner and could function through both EGFR and IGF1R signaling. Finally, we incorporated a Padi4-/- allele into our tumor model to genetically block NETosis and observed complete rescue of the accelerated tumor onset and increased penetrance observed in Dicer1+/- mice, demonstrating that NETosis promotes the growth of Dicer1+/- FN-RMS tumors. Importantly, these findings may be applicable to many DICER1 syndrome-associated cancers, as neutrophils which get converted to tumor promoters by heterozygous DICER1 loss are present in DICER1 syndrome patients regardless of tumor type. Citation Format: Randolph Larsen, Jason Hanna, Kristin Reed, Hongjian Jin, Wood Kimbrough, Kyna Vuong, Myron Evans, Casey Langdon, Catherine Drummond, Matthew Garcia, David Finkelstein, Patrick Schreiner, Jerold Rehg, Mark Hatley. Germline DICER1 loss promotes rhabdomyosarcoma via innate immune system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5463.

Metabolic regulation of neutrophil functions in homeostasis and diseases.

Neutrophils are the most abundant leukocytes in humans and play a role in the innate immune response by being the first cells attracted to the site of infection. While early studies presented neutrophils as almost exclusively glycolytic cells, recent advances show that these cells use several metabolic pathways other than glycolysis, such as the pentose phosphate pathway, oxidative phosphorylation, fatty acid oxidation, and glutaminolysis, which they modulate to perform their functions. Metabolism shifts from fatty acid oxidation-mediated mitochondrial respiration in immature neutrophils to glycolysis in mature neutrophils. Tissue environments largely influence neutrophil metabolism according to nutrient sources, inflammatory mediators, and oxygen availability. Inhibition of metabolic pathways in neutrophils results in impairment of certain effector functions, such as NETosis, chemotaxis, degranulation, and reactive oxygen species generation. Alteration of these neutrophil functions is implicated in certain human diseases, such as antiphospholipid syndrome, coronavirus disease 2019, and bronchiectasis. Metabolic regulators such as AMPK, HIF-1α, mTOR, and Arf6 are linked to neutrophil metabolism and function and could potentially be targeted for the treatment of diseases associated with neutrophil dysfunction. This review details the effects of alterations in neutrophil metabolism on the effector functions of these cells.

Vitamin A deficiency impairs neutrophil-mediated control of Salmonella via SLC11A1 in mice

In sub-Saharan Africa, multidrug-resistant non-typhoidal Salmonella serovars are a common cause of fatal bloodstream infection. Malnutrition is a predisposing factor, but the underlying mechanisms are unknown. Here we show that vitamin A deficiency, one of the most prevalent micronutrient deficits afflicting African children, increases susceptibility to disseminated non-typhoidal Salmonella disease in mice and impairs terminal neutrophil maturation. Immature neutrophils had reduced expression of Slc11a1, a gene that encodes a metal ion transporter generally thought to restrict pathogen growth in macrophages. Adoptive transfer of SLC11A1-proficient neutrophils, but not SLC11A1-deficient neutrophils, reduced systemic Salmonella burden in Slc11a1−/− mice or mice with vitamin A deficiency. Loss of terminal granulopoiesis regulator CCAAT/enhancer-binding protein ϵ (C/EBPϵ) also decreased neutrophil-mediated control of Salmonella, but not that mediated by peritoneal macrophages. Susceptibility to infection increased in Cebpe−/−Slc11a1+/+ mice compared with wild-type controls, in an Slc11a1-expression-dependent manner. These data suggest that SLC11A1 deficiency impairs Salmonella control in part by blunting neutrophil-mediated defence.

CD14-CD10-CD45+HLA-DR-SSC+ neutrophils may be granulocytic myeloid-derived suppressor cell-like cells and relate to disease progression in non-Hodgkin's lymphoma patients.

We explored the frequency of CD14-CD10-CD45+HLA-DR-SSC++ neutrophils (CD10- neutrophils) in patients with non-Hodgkin's lymphoma (NHL), and their immunologic characteristics and clinical significance. Patients with NHL who were newly diagnosed (NDP; n = 33), in remission (RMP; n = 28) and relapsed (RLP; n = 29) were included, and 47 volunteers were recruited as healthy controls (HCs). The frequency of CD10- neutrophils in the peripheral blood from HC and patients with NHL was detected. CD10- and CD10+ neutrophils were sorted, and their cytology was analyzed. CD3+ T cells were also isolated and cultured with the autologous CD10- or CD10+ neutrophils, after which the proliferation and death rates of T cells were determined. The levels of arginase-1 (Arg-1) and reactive oxygen species (ROS) in CD10+ or CD10- neutrophils were examined. Few CD10- neutrophils were detected in HCs but were significantly elevated in patients with NHL, especially in NDP and RLP. In addition, CD10- neutrophils in NDP with advanced stage and high risk were markedly higher than those in NDP with limited stage and low risk. In RMP and RLP, the relapse-free survival and overall survival in patients with high CD10- neutrophils were shorter than those with low CD10- neutrophils. CD10- neutrophils from patients with NHL, which mainly consist of immature neutrophils, inhibit T-cell proliferation and facilitate T-cell death. Furthermore, a significant increase was observed in Arg-1 expression, along with an increase to a certain extent in ROS. CD10- neutrophils in patients with NHL have characteristics of myeloid-derived suppressor cells and may be related to disease progression and poor prognosis.

The Relationship between Serum Zonulin and Innate Immunity in Patients with Inflammatory Bowel Disease

The aim of the study was to investigate the relationship between the serum zonulin and the cellular immunity in patients with ulcerative colitis (UC) and Crohn’s disease (CD). The study included 97 patients, 13 (13.4%) patients with CD and 84 (86.6%) patients with UC. The concentration of zonulin in the serum was studied using the ELISA kits. The investigation of the circulated leukocyte subpopulation was carried out through flow cytometry. The functional activity of the circulating neutrophils was studied using the absorption capacity of the monodisperse polystyrene latex particles and indicators of oxygen-dependent metabolism in the nitroblue tetrazolium test. The serum zonulin concentration in CD patients was significantly higher compared with UC patients (p = 0.003). The zonulin concentration directly correlated with the functional activity of the circulating neutrophils. Patients with a zonulin concentration > 472.4 pg/mL had a significantly higher number of band neutrophils (p = 0.0104), CD3+CD8+ cells (p = 0.0212), NK cells (p = 0.0161), and lower–CD19+ cells (p = 0.0034). Among the IBD patients, zonulin was associated with IBD severity. An increase in the serum concentration of zonulin was associated with an increase in the functional activity of circulating neutrophils and an increase in the number of CD3+CD8+ cells, NK cells, and a decrease in the number of CD19+ cells.

Changes in the level of C-reactive protein depending on the severity of localized periodontitis of traumatic etiology

BACKGROUND: The significant prevalence and course of inflammatory periodontal diseases are associated not only with the presence of known bacterial agents, but also with changes in the body’s immune system that occur as a result of aging.
 AIM: To establish the relationship between the level of C-reactive protein in the blood and the course of localized periodontitis of traumatic etiology.
 MATERIAL AND METHODS: During 2016–2019 169 patients with localized periodontitis of traumatic etiology (average age 56.44±0.14 years) of mild (102 people) and moderate (67 patients) severity at the Department of General Practice Dentistry of the North-Western State Medical University named after I.I. Mechnikov were examined. An in-depth dental examination, determination of periodontal indices, assessment of laboratory parameters (determination of high-sensitivity C-reactive protein, assessment and calculation of the entropy of the blood leukocyte formula), complex treatment using splinting with orthopedic structures in the main group (69 patients) and without it in the comparison group (57 people) were carried out. Statistical processing of data was conducted using the Shapiro–Wilk, Pearson, Kolmogorov–Smirnov tests, Fisher’s exact test and χ2 test, and calculation of relative risk.
 RESULTS: Oral hygiene was good (hygiene index 0.54±0.18) and satisfactory (hygiene index 0.79±0.21) with mild and moderate severity, respectively. The local Mulleman–Cowell index was increased by 2.7 times (1.43±0.50) with mild severity and almost 4 times (2.31±0.33) with moderate severity of localized periodontitis of traumatic etiology compared with general index (0.52±0.12; 0.64±0.18). In localized periodontitis of traumatic etiology of mode¬rate severity, an increase in the number of monocytes (8.7±2.12×109/l) and band neutrophils (5.4±1.47×109/l), an increase in the relative entropy of the leukocyte blood count (72.3±21.12%) compared with mild severity (62.8±14.9%; p=0.00089) were identified. With C-reactive protein concentrations ranging from 3 to 10 mg/l, the risk of developing localized periodontitis of moderate traumatic etiology increased by 1.74 times compared with C-reactive protein levels of less than 3 mg/l (p=0.0022).
 CONCLUSION: In localized periodontitis of moderate traumatic etiology, an increase in the number of band neutrophils and monocytes, as well as the relative entropy of the leukocyte blood count was detected. Preclinical increases in the concentration of C-reactive protein contribute to an increase in the severity of the disease.

Disruption of the Functional Activity of Neutrophil Granulocytes as a Risk Factor for the Development of Lung Damage in Pregnant Women with COVID-19.

Currently, the assessment of immune status in patients with COVID-19 is limited to determining the count of polymorphonuclear leukocytes and the phagocytic function of neutrophils, which is insufficient to understand the regulatory role of innate immunity cells in the development of pneumonia. However, no such studies have been conducted in pregnant women with COVID-19. The aim of this study was to investigate the functional state of neutrophil granulocytes in order to identify predictors of pneumonia severity risk in pregnant women with COVID-19. A clinical characterization of pregnant women with COVID-19 in addition to minimal and average lung changes was provided. The composition and ratio of morphological forms of leukocyte cells were studied. Cytochemical studies of neutrophil granulocytes were carried out and calculations of the mean cytological index (MCI) for succinate dehydrogenase, myeloperoxidase, and cationic proteins were performed. The number of NETs in blood smears was counted. Independent predictors of pneumonia severity in pregnant women with COVID-19 were calculated using regression analysis. The quality of the model was assessed using ROC analysis. In pregnant women with COVID-19 and an average volume of lung changes, the number of polymorphonuclear leukocytes (p = 0.03) and band neutrophils (p = 0.002) in the blood was significantly higher than in pregnant women with minimal lung changes. The MCI indicators of succinate dehydrogenase, cationic proteins, and myeloperoxidase in pregnant women with COVID-19 were reduced in relation to the control group (p < 0.0001). In blood smears of pregnant women with COVID-19 and an average volume of lung changes, the number of NETs increased (p = 0.002). Regression analysis showed that succinate dehydrogenase and NETs are independent predictors of pneumonia severity in pregnant women with COVID-19. Our study confirms the prognostic significance of low levels of neutrophilic succinate dehydrogenase and high levels of NETs in the blood of pregnant women with COVID-19. The combination of these two biomarkers is a significant reflection of the severity of pneumonia development in pregnant women with COVID-19. However, further research is needed to identify the mechanisms underlying this association.

Association of leukergy (in vitro leukocyte aggregation) with systemic inflammation in dogs and cats (2017-2022).

Leukergy is the phenomenon of aggregation of leukocytes on a peripheral blood film, and in humans, it is used as an indicator of systemic inflammation and infection. To assess the association of leukergy on blood film examination with biochemical and clinical evidence of systemic inflammation, infection, neoplasia, or specific organ system disease. A case-control study using retrospective analysis (2017-2022) identified all canine and feline patients that had been presented to an academic referral center with a finding of leukergy on peripheral blood film and an equal number of species-matched controls. A total of 127 cases (canine n = 44, feline n = 83) were identified, as well as 127 controls. Feline samples were 7.6× more likely to exhibit leukergy (0.019%) than canine (0.0025%). A positive association was noted between leukergy and higher globulin concentrations in dogs (marginal difference 0.5 mg/dL, P = .016) and cats (marginal difference 0.67 mg/dL, P = <.001). Cats with leukergy had higher WBC counts and were less likely to be diagnosed with cardiac or urinary tract disease than controls. Dogs with leukergy had lower WBC counts and were more likely to be febrile but were less likely to have urinary tract disease than controls. No association was found with neutrophil toxic change or band forms, systemic antimicrobial therapy, or signalment. We conclude that there is a positive association between increased globulin concentrations and leukergy and inconsistent associations between leukergy and other markers of inflammation or infection. Leukergy is rare overall but markedly more common in cats than dogs.

Haematological Profile and Surgical Management of Lumpy Jaw Condition (Actinomycosis) in Crossbred Cattle

A case series study was conducted from December 2022 to August 2023 in cattle referred to the Veterinary Dispensary Peddaputta village of Kadapa district. Total 6 cross bred cattle were diagnosed and most of them referred with swelling at the mandibular region showing leakage of pus and it was diagnosed as bovine Actinomycosis or lumpy jaw condition. Haematology revealed significant erythrocytopenia, higher PCV, lower haemoglobin concentration, significant leucocytosis with neutrophilia, presence of a greater number of immature neutrophils and decreased lymphocyte count. With the surgical intervention granulomatous tissue and pus was removed, and antibiotics like long acting Terramycin injection two doses within 48 hours, along with oral administration of Potassium Iodide and external dressing of wound with 2% povidone iodine. The animal recovered successfully within 12 days of post treatment.

Deterministic reprogramming of neutrophils within tumors.

Neutrophils are increasingly recognized as key players in the tumor immune response and are associated with poor clinical outcomes. Despite recent advances characterizing the diversity of neutrophil states in cancer, common trajectories and mechanisms governing the ontogeny and relationship between these neutrophil states remain undefined. Here, we demonstrate that immature and mature neutrophils that enter tumors undergo irreversible epigenetic, transcriptional, and proteomic modifications to converge into a distinct, terminally differentiated dcTRAIL-R1+ state. Reprogrammed dcTRAIL-R1+ neutrophils predominantly localize to a glycolytic and hypoxic niche at the tumor core and exert pro-angiogenic function that favors tumor growth. We found similar trajectories in neutrophils across multiple tumor types and in humans, suggesting that targeting this program may provide a means of enhancing certain cancer immunotherapies.

Single-Cell RNA Sequencing Reveals Alterations in Patient Immune Cells with Pulmonary Long COVID-19 Complications.

Since the emergence of the COVID-19 pandemic, the effects of SARS-CoV-2 have been extensively researched. While much is already known about the acute phase of the infection, increasing attention has turned to the prolonged symptoms experienced by a subset of individuals, commonly referred to as long COVID-19 patients. This study aims to delve deeper into the immune landscape of patients with prolonged symptoms by implementing single-cell mRNA analysis. A 71-year-old COVID-19 patient presenting with persistent viral pneumonia was recruited, and peripheral blood samples were taken at 3 and 2 years post-acute infection onset. Patients and control peripheral blood mononuclear cells (PBMCs) were isolated and single-cell sequenced. Immune cell population identification was carried out using the ScType script. Three months post-COVID-19 patients' PBMCs contained a significantly larger immature neutrophil population compared to 2-year and control samples. However, the neutrophil balance shifted towards a more mature profile after 18 months. In addition, a notable increase in the CD8+ NKT-like cells could be observed in the 3-month patient sample as compared to the later one and control. The subsequent change in these cell populations over time may be an indicator of an ongoing failure to clear the SARS-CoV-2 infection and, thus, lead to chronic COVID-19 complications.

Flow cytometric-based detection of CD80 is a useful diagnostic marker of acute myeloid leukemia in dogs.

CD80, a co-stimulatory molecule required for optimal T cell activation, is expressed on antigen-presenting cells, including monocytes and dendritic cells, in dogs and humans. We hypothesized that CD80 would be expressed on tumor cells in dogs from acute myeloid leukemia (AML) but not dogs with lymphoid neoplasms. We first evaluated the cellular staining pattern of a hamster anti-murine CD80 antibody (clone 16-10A1, ThermoFisher Scientific Cat# 17-0801-82, RRID: AB_469417) in blood and bone marrow aspirates from healthy dogs. Using flow cytometric analysis and examination of modified Wright's-stained cytologic smears of unsorted and flow cytometric or immunomagnetic bead-sorted leukocytes, we show that the antibody binds to mature and immature neutrophils and monocytes, but not lymphocytes or eosinophils, in blood and bone marrow. We then added the antibody to routine flow cytometric panels for immunophenotyping hematopoietic neoplasms in dogs. We found that the antibody labeled tumor cells in 72% of 39 dogs with AML and 36% of 11 dogs with acute leukemia expressing lymphoid and myeloid markers ("mixed lineage") but none of the dogs with B (n = 37) or T (n = 35) lymphoid neoplasms. A higher proportion of tumor cells in dogs with AML were labeled with the anti-CD80 antibody vs antibodies against other myeloid-associated antigens, including CD4 (36%, p = 0.003), CD11b (44%), CD11c (46%), CD14 (38%, p = 0.006) and CD18 (59%, clone YFC118). In contrast, antibodies against CD11b and CD11c bound to tumor cells in 8-32% of the lymphoid neoplasms. We show that CD80, as detected by antibody clone 16-10A1, is a sensitive and specific marker for AML and would be useful to include in flow cytometric immunophenotyping panels in dogs.

Hematological analysis as a method of monitoring physiological status of medium carnivorous mammals in the Russian Far East

Clinical blood analysis is considered not only a method of assessing the health status of individuals, but also their fitness and welfare, although the interpretation of the obtained data is complicated by the combined influence of various factors. For most wild carnivore species, there is insufficient information about the effect of environmental factors on hematological parameters. Mammals in the Far East are exposed to hard seasonal climate changes, and therefore have physiological adaptations that enable them to survive the cold season. The aim of this study was to estimate the hematological parameters of three widespread species of medium carnivorous mammals in this region, namely Meles leucurus amurensis, Prionailurus bengalensis euptilura, and Nyctereutes procyonoides ussuriensis, taking into account such factors as sex, age and season in the Ussuriisky State Nature Reserve (Russia), as well as to identify the most informative blood indicators of the animal physiological status. In spring and autumn of 2014–2023, blood samples were collected from 103 individuals of the studied carnivores. The animals were captured, immobilised, blood-sampled and released in the wild at the capture site. The number of leucocytes was counted in the field, and their ratio was detected on the blood smears in the lab. The absence of sex differences and the presence of age differences in the studied species were revealed, which corresponds to the already known data on the parameters of mammalian blood. In spring, Nyctereutes procyonoides ussuriensis had higher leucocyte count (14.77 ± 1.76 mln/ml and 12.33 ± 1.08 mln/ml (hereinafter, in spring vs. autumn, respectively)), the ratio of neutrophils to lymphocytes (4.87 ± 0.47 and 3.02 ± 0.28), and the percentage of segmented neutrophils (73.12 ± 1.77% and 62.95 ± 2.29%), and the lower percentage of lymphocytes (20.35 ± 1.45% and 25.64 ± 1.49%) compared to autumn. Similar blood patterns were observed in two other species. This may be the result of a decrease in body mass and poor condition of animals, i.e. physiological stress after a long winter period and a lack of food resources. In addition, Nyctereutes procyonoides ussuriensis had higher percentages of eosinophils, basophils, and band neutrophils (7.85 ± 1.61%, 3.69 ± 1.26%, 2.15 ± 0.34%, respectively) than Meles leucurus amurensis (2.55 ± 1.09%, 0.45 ± 0.17%, 0.55 ± 0.18%, respectively) and Prionailurus bengalensis euptilura (1.48 ± 0.59%, 0.30 ± 0.16%, 1.74 ± 0.47%, respectively). These differences are probably determined by the biological characteristics of Nyctereutes procyonoides ussuriensis, since this species is an ideal host and carrier of various diseases, and it also has specific morphological features of blood cells. Thus, our results demonstrate the importance of systematic blood tests and the necessity of considering both species-specific characteristics and environmental factors for assessing animal health.