Percentage Of Natural Killer Cells Research Articles

Accumulation of CD56+ CD16- Natural Killer Cells in Response to Preoperative Chemotherapy for Breast Cancer.

The activation of the antitumor immune responses of T cells and natural killer (NK) cells is important to induce breast tumor shrinkage via preoperative chemotherapy. We evaluated how antitumor immune responses contribute to the effects of such therapy. Forty-three patients with stages I - IV breast cancer who underwent surgery between August 2018 and Jun 2023 after preoperative chemotherapy were enrolled. Peripheral natural killer (pNK) cell activity was assessed by 51Cr-release assay, and the counts and percentages of CD4+, CD8+, and NK cells and their subsets in peripheral blood were measured before and after chemotherapy by two-color flow cytometry. Associations of cell population changes with chemotherapy responses were analyzed. On univariate analysis, relative to grade (G) ≤ 1 effects, G ≥ 2 therapeutic effects were associated significantly with human epidermal growth factor receptor 2 (HER-2)+ breast cancer (P = 0.024) and post-chemotherapy CD56+ CD16- NK cell accumulation (8.4% vs. 5.5%, P = 0.042), and tended to be associated with increased pre-chemotherapy CD56+ CD16- NK cell percentages (5.4% vs. 3.3%, P = 0.054) and pNK cell activity (42.0% vs. 34.5%, P = 0.057). The accumulation and increased percentage of CD56+ CD16- NK cells in patients with G ≥ 2 effects were not associated with changes in pNK cell activity or the disappearance of axillary lymph-node metastases. On multivariate analysis, G ≥ 2 therapeutic effects tended to be associated with higher pre-chemotherapy pNK levels (odds ratio = 0.96; 95% confidence interval: 0.921 - 1.002; P = 0.067). The accumulation of the immunoregulatory CD56+ CD16- NK cell subset in the peripheral blood before and after chemotherapy may lead to the production of cytokines that induce an antitumor immune response. Activation of the immune response mediated by CD56+ CD16- pNK cells after chemotherapy and their high counts before chemotherapy may contribute to the improvement of therapeutic effects against breast cancer.

Addition of CD14 improves discrimination of lymphocytes in the TBNK phenotyping panel.

Peripheral blood lymphocyte phenotyping panels typically include CD45 for discrimination of the lymphocyte population, and fluorophore-conjugated monoclonal antibodies to identify T, B, and Natural Killer (NK) cells. While CD45 combined with side scatter is generally sufficient to clearly distinguish lymphocytes from monocytes in the majority of peripheral blood samples, it is challenging to accurately gate lymphocytes in samples from patients with monocytosis or significant lymphopenia, or from very young infants. Addition of a monocyte marker to lymphocyte phenotyping panels for monocyte exclusion has previously been evaluated for improved discrimination of lymphocytes, albeit largely in healthy donor adult samples. Here we evaluate the effect of the addition of CD14 to a standard lymphocyte phenotyping panel on total lymphocyte, T, B, and NK cell percentages in a predominantly pediatric population of patients under evaluation chiefly for immunodeficiency, immune-depletion, or immune reconstitution. Addition of CD14 to the standard lymphocyte phenotyping improved discrimination of lymphocytes from monocytes, resulted in decreased NK cell percentages, likely because CD16+ and/or CD56+ monocytes were included in the CD56+CD16+ NK cell gate with conventional gating, and although less significant, resulted in an increased percentage of B cells, since relatively larger B cells were likely gated out by more restrictive light scatter gating used with the conventional gating approach. The change in NK and B cell percentages were more pronounced in samples from patients below a year of age, and in patients who were relatively lymphopenic. These data suggest that addition of CD14 to conventional lymphocyte phenotyping panels that utilize CD45 versus side scatter gating results in significant improvement in the accuracy of lymphocyte gating, and accurate quantification of NK and B cells particularly in samples from infants and lymphopenic individuals.

Overactivated MX1 Positive Natural Killer Cells Promote the Progression of Sepsis-Induced Acute Respiratory Distress Syndrome.

Natural killer (NK) cells are key regulators of immune defense in sepsis-induced acute respiratory distress syndrome (ARDS), yet the characteristics of NK cell clusters in ARDS remain poorly understood. A prospective and observational study enrolled septic patients with ARDS or not was conducted to determine the percentage of NK cells via flow cytometry. The transcriptomes of peripheral blood mononuclear cells (PBMCs) from healthy controls, patients with sepsis only, and patients with sepsis-induced ARDS were profiled. Vitro experiments were performed to confirm the mechanism mediating MX1+NK cell infiltration. A total of 115 septic patients were analyzed, among whom 63 patients developed ARDS and 52 patients did not. Decreased NK percentages were found in sepsis with ARDS patients (%, 7.46±4.40 vs 11.65±6.88, P=0.0001) compared with sepsis-only patients. A lower percentage of NK cells showed a significant increase in 28-day mortality. Single-cell sequencing analysis revealed distinct characteristics of NK cells in sepsis-induced ARDS, notably the identification of a unique cluster defined as MX1+NK cells. Flow cytometry analysis showed an elevated percentage of MX1+NK cells specifically in individuals with sepsis-induced ARDS, compared with patients with sepsis only. Pseudo-time analysis showed that MX1+NK cells were characterized by upregulation of type I interferon-induced genes and other pro-inflammatory genes. MX1+NK cells can respond to type I interferons and secrete type I interferons themselves. Ligand-receptor interaction analysis also revealed extensive interaction between MX1+NK cells and T/B cells, leading to an uncontrolled inflammatory response in ARDS. MX1+NK cells can respond to type I interferons and secrete type I interferons themselves, promoting the development of sepsis-induced ARDS. Interfering with the infiltration of MX1+NK cells could be a therapeutic approach for this disease. Due to the limited sample size, a larger sample size was needed for further exploration.

A comparative study of general and severe mycoplasma pneumoniae pneumonia in children

ObjectivesThe increasing prevalence of severe Mycoplasma pneumoniae pneumonia (SMPP) poses a significant threat to the health of children. This study aimed to characterise and assess the outcomes in children with SMPP.MethodsWe retrospectively analysed children hospitalised for M. pneumoniae pneumonia (MPP) between January and December 2022. Retrospectively, demographic, clinical, underlying diseases, laboratory and radiological findings, and treatment outcomes were collected and analysed. Disease severity was defined as severe or general according to the Guideline for diagnosis and treatment of community-acquired pneumonia in children (2019 version).ResultsOver a 12-month observation period, 417 children with MPP were enrolled, 50.6% (211/417) of whom had SMPP, with the peak incidence observed in winter. Of the 211 children with SMPP, 210 were treated and discharged with improvement, while one child with congenital heart disease died of cardioembolic stroke. A significantly higher proportion of patients with SMPP had underlying diseases, extrapulmonary complications (myocardial and digestive system involvement), and bacterial co-infection. A total of 25 (12%) children with SMPP received mechanical ventilation. The median duration of mechanical ventilation was 3 days. All children were treated with macrolide antibiotic. A significantly higher proportion of patients with SMPP received antibiotic other than macrolides, methylprednisolone sodium succinate, intravenous immunoglobulin and anticoagulation, compared with patients with general MPP (GMPP). Children with SMPP had significantly higher levels of white blood cells, neutrophil percentage, C-reactive protein, procalcitonin, interferon-γ, interleukin (IL)-2, IL-5, IL-6, IL-8, IL-10 and significantly lower percentages of lymphocytes, monocytes, and natural killer cells, compared with GMPP group.ConclusionOur findings suggest that severely ill children have more pronounced inflammatory reaction and extrapulmonary complications. For effective management of children with SMPP, hormonal, prophylactic, anticoagulant therapy, as well as the use of antibiotics other than macrolides for bacterial co-infections, could be incorporated into treatment regimens.

Peripheral NK cells identified as the predictor of response in extensive-stage small cell lung cancer patients treated with first-line immunotherapy plus chemotherapy.

Although immunotherapy improves outcomes in extensive-stage small-cell lung cancer (ES-SCLC), the search for biomarkers predicting treatment success is crucial. Natural killer (NK) cells are potential indicators in various cancers, however, their precise role in ES-SCLC prognosis remains unclear. In this retrospective study, 33 patients with ES-SCLC treated with first-line immuno-chemotherapy were enrolled. The peripheral NK cell percentage and its longitudinal dynamics were analyzed using flow cytometry. Progression-free survival (PFS) and overall survival (OS) were calculated as hazard ratio (HR) and compared statistically. The median PFS was better in the group with normal baseline NK cell levels than the low group (7.0 vs. 4.6months; HR = 0.17; 95% CI 0.07-0.41; P < 0.0001), but there was no association with OS (14.9 vs. 10.3months; HR = 0.55; 95% CI 0.23-1.31; P = 0.171). Furthermore, the NK cell% for 95.0% of patients increased after immunochemotherapy in the clinical response group (P = 0.0047), which led to a better median PFS (6.3 vs. 2.1months; HR = 0.23; 95% CI 0.05-0.98; P < 0.0001) and OS (14.9 vs. 5.9months; HR = 0.20; 95% CI 0.04-1.02; P < 0.0001). Similar trends were observed with NK cell% changes up to disease progression, improving PFS (6.5 vs. 4.3; HR = 0.41; 95% CI 0.12-0.92; P = 0.0049) and OS (17.4 vs. 9.7; HR = 0.42; 95% CI 0.17-1.02; P < 0.0001). In patients with ES-SCLC, the percentage and changes in peripheral NK cells can predict the response to combined immunotherapy and chemotherapy.

Reduced expressions of apoptosis-related proteins TRAIL, Bcl-2, and TNFR1 in NK cells of juvenile-onset systemic lupus erythematosus patients: relations with disease activity, nephritis, and neuropsychiatric involvement.

Lupus pathogenesis is mainly ascribed to increased production and/or impaired clearance of dead cell debris. Although self-reactive T and B lymphocytes are critically linked to lupus development, neutrophils, monocytes, and natural killer (NK) cells have also been implicated. This study assessed apoptosis-related protein expressions in NK cells of patients with juvenile-onset systemic lupus erythematosus (jSLE) and relations to disease activity parameters, nephritis, and neuropsychiatric involvement. Thirty-six patients with jSLE, 13 juvenile dermatomyositis (JDM) inflammatory controls, and nine healthy controls had Fas, FasL, TRAIL, TNFR1, Bcl-2, Bax, Bim, and caspase-3 expressions in NK cells (CD3-CD16+CD56+) simultaneously determined by flow cytometry. Disease activity parameters included Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score, erythrocyte sedimentation rate, C-reactive protein level, anti-double strain DNA antibody level, complement fractions C3 and C4 levels. Patients with jSLE had a profile of significantly reduced expression of TRAIL, Bcl-2, and TNFR1 proteins in NK cells when compared to healthy controls. Similar profile was observed in patients with jSLE with active disease, positive anti-dsDNA, nephritis, and without neuropsychiatric involvement. Patients with jSLE with positive anti-dsDNA also had reduced expression of Bax in NK cells when compared healthy controls and to those with negative anti-dsDNA. Yet, patients with jSLE with negative anti-dsDNA had reduced mean fluorescence intensity (MFI) of Bim in NK cells compared to healthy controls. Patients with jSLE with nephritis also had reduced MFI of Fas in NK cells when compared to those without nephritis. In addition, in patients with jSLE, the proportion of FasL-expressing NK cells directly correlated with the SLEDAI-2K score (rs = 0.6, p = 0.002) and inversely correlated with the C3 levels (rs = -0.5, p = 0.007). Moreover, patients with jSLE had increased NK cell percentage and caspase-3 protein expression in NK cells when compared to JDM controls. This study extends to NK cells an altered profile of TRAIL, Bcl-2, TNFR1, Fas, FasL, Bax, Bim, and caspase-3 proteins in patients with jSLE, particularly in those with active disease, positive anti-dsDNA, nephritis, and without neuropsychiatric involvement. This change in apoptosis-related protein expressions may contribute to the defective functions of NK cells and, consequently, to lupus development. The full clarification of the role of NK cells in jSLE pathogenesis may pave the way for new therapies like those of NK cell-based.

Immune cells at the feto-maternal interface: Comprehensive characterization and insights into term labor

Immune cells at the feto-maternal interface play an important role in pregnancy; starting at implantation, maintenance of pregnancy, and parturition. The role of decidual immune cells in induction of labor still needs to be understood. Published reports on this topic show heterogeneity in methods of cell isolation, assay, analysis and cellular characterization making it difficult to collate available information in order to understand the contribution of immune cells at term leading to parturition. In the present study, available literature was reviewed to study the differences in immune cells between the decidua basalis and decidua parietalis, as well as between immune cells in term and preterm labor. Additionally, immune cells at the decidua parietalis were isolated from term not in labor (TNL) or term in labor (TL) samples and characterized via flow cytometry using a comprehensive, high-dimensional antibody panel. This allowed a full view of immune cell differences without combining multiple studies, which must include variation in isolation and analysis methods, for more conclusive data. The ratio of cells found in decidua parietalis in this study generally matched those reported in the literature, although we report a lower percentage of natural killer (NK) cells at term. We report that CD4 expression on CD8- NK cells decreased in term labor compared to not in labor samples, suggesting that natural killer cells may be migrating to other sites during labor. Also, we report a decrease in CD38 expression on CD8+ CD57+ T cells in labor, indicative of cytotoxic T cell senescence. Our study provides a comprehensive status of immune cells at the decidua-chorion interface at term.

Ozanimod-mediated remission in experimental autoimmune encephalomyelitis is associated with enhanced activity of CNS CD27low/- NK cell subset.

Ozanimod (RPC1063) is an immunomodulator that has been recently approved by the FDA (2020) for the treatment of relapsing-remitting multiple sclerosis (RRMS). It is a selective agonist of the sphingosine-1-phophate receptors 1 and 5, expressed on naïve and central memory T and B cells, as well as natural killer (NK) cells, and is involved in lymphocyte trafficking. Oral administration of ozanimod was reported to result in rapid and reversible reduction in circulating lymphocytes in multiple sclerosis (MS) patients, however, only minimal effect on NK cells was observed. In this study, we sought to investigate the effect of ozanimod on NK cells and assess whether they play any role in ozanimod-induced remission in experimental autoimmune encephalomyelitis (EAE), the animal model of MS. Active EAE induction was done in C57BL/6 female mice, followed by daily oral treatment with ozanimod (0.6mg/kg) starting at disease onset (score 1). Flow cytometry of blood and CNS was performed 24 hours after the last oral dose of ozanimod treatment in diseased mice. Histological analysis of lumbar spinal cord was performed for evaluating the level of inflammation and demyelination. Depletion of peripheral NK cells was done using anti-NK1.1 mouse antibody (mAb) at day 5 post-EAE induction. Ozanimod was effective in reducing the clinical severity of EAE and reducing the percentage of autoreactive CD4+ and CD8+ T cells along with significant inhibition of lymphocyte infiltration into the spinal cord, accompanied by reversed demyelination. Furthermore, ozanimod treatment resulted in a significant increase in the frequency of total NK cells in the blood and CNS along with upregulation of the activating receptor NKG2D on CD27low/- NK cell subset in the CNS. The effectiveness of ozanimod treatment in inhibiting the progression of the disease was reduced when NK cells were depleted using anti-NK1.1 mAb. The current study demonstrated that ozanimod treatment significantly improved clinical symptoms in EAE mice. Ozanimod and anti-NK1.1 mAb appear to function in opposition to one another. Collectively, our data suggest that ozanimod-mediated remission is associated with an increased percentage of total NK cells and CD27low/- NK cells expressing the activating receptor, NKG2D in the CNS.

Analysis and validation of potential ICD-related biomarkers in development of myopia using machine learning.

We aimed to identify and verify potential biomarkers in the development of myopia associated with immunogenic cell death (ICD). We download high myopia (HM) dataset GSE136701 from Gene Expression Omnibus. Differentially expressed genes in HM were identified to overlapped with ICD-related genes. Least absolute shrinkage and selection operator were used to select the Hub genes. Furthermore, the correlation between the hub genes and immune infiltration, immune response activities, and hub genes Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis was investigated using Spearman's rank correlation. Prediction of the miRNAs upstream of the Hub genes was based on the TargetScan database. We used guinea pig lens-induced myopia model's scleral tissues performed quantitative real-time polymerase chain reaction. We identified overlapped with ICD-related genes (LY96, IL1A, IL33, and AGER) and two genes (LY96 and AGER) as hub genes. Single sample gene set enrichment analysis and Spearman's rank correlation revealed that hub gene expression levels in HM were significantly correlated with the infiltration percentages of CD56dim natural killer cells, macrophages, immature B cells, and the immune response activities of APC co-stimulation and Kyoto Encyclopedia of Genes and Genomes pathways, such as terpenoid backbone biosynthesis, aminoacyl-trna biosynthesis, Huntington's disease, oxidative phosphorylation; there were a few additional signaling pathways compared to normal samples. Additionally, several miRNA were predicted as upstream regulators of LY96 and AGER. LY96 was identified as a significantly differentially expressed biomarker in myopia guinea pig's scleral tissues, as verified by qPCR. LY96 was identified and verified as a ICD-related potential myopia biomarker. Molecular mechanisms or pathways involved in myopia development by LY96 requires further research.

Association of lymphocyte subsets and cytokines with bone metabolism: a retrospective, cross-sectional study

BackgroundPrevious research has shown that lymphocytes and cytokines can mediate bone metabolism. This study explored the clinical association and predictive ability of lymphocytes and cytokines levels for bone metabolism.MethodsA total of 162 patients were enrolled in this study. The levels of N-terminal propeptide of type I procollagen (P1NP), β-collagen degradation product (β-CTX), total T lymphocytes, immature T lymphocytes, suppressor/cytotoxic T lymphocytes, helper/inducer T lymphocytes, B lymphocytes, natural killer (NK) cells, Interferon-gamma (IFN-γ), tumour necrosis factor-alpha (TNF-α), IFN-α, interleukin-1 beta (IL-1β), IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, and IL12p70 were evaluated. The relationship between these lymphocyte subsets and cytokines with bone metabolic status was examined and their predictive ability for bone metabolic status was assessed.ResultsThe principal component analysis (PCA) and correlation analysis results varied on differences in lymphocyte subsets and cytokines in various bone metabolism states. Differential analysis revealed significant differences in the absolute counts of B lymphocytes (P < 0.05), level of IL-12p70 (P < 0.05), and IL-8 (P < 0.001) at different P1NP levels. Significant differences were observed in the absolute counts of total T lymphocytes (P < 0.05), B lymphocytes (P < 0.05), the level of IL-6 (P < 0.05), the percentage of B lymphocytes (P < 0.01), and NK cells (P < 0.05) at different β-CTX levels. Furthermore, the receiver operating characteristic (ROC) curve showed that the absolute count of B lymphocytes and levels of IL-12p70 and IL-8 could be used to evaluate bone formation states, while the absolute counts of T and B lymphocytes, level of IL-6, and percentages of NK cells and B lymphocytes could be used to evaluate bone resorption states.ConclusionThe bone metabolism status changed based on the lymphocyte subsets and cytokine levels. Differentially expressed lymphocytes and cytokines could be used to distinguish bone metabolism status.

Evaluation of klotho expression on peripheral blood lymphocytes among hemodialysis patients and its possible contribution to their immuno-compromised status

Infection is the second most common cause of mortality among end-stage kidney disease (ESKD) patients. Uremic toxins are the main cause of impaired immune response among ESKD patients. Klotho gene, the anti-aging gene, encodes the transmembrane alpha klotho (αKL) protein which acts as an obligate coreceptor for fibroblast growth factor 23 (FGF23). Klotho protein may play a role in immune cell functions, particularly in anti-inflammatory response; however, its role is still incompletely understood. In the present study, we aimed to measure αKL protein expression on peripheral blood lymphocytes (PBLs) among hemodialysis (HD) patients, and we assumed that decreased αKL expression on PBLs may contribute to the impaired immunity among HD patients. This case-control study included 20 ESKD patients on regular hemodialysis for more than 3 months. Their ages ranged from 24 to 69 years. Patients with primary immunodeficiencies, those on systemic immunosuppressive drugs, those with ongoing infections or who had recently recovered from infections, and those with malignancies on active treatment were excluded. A control group of 20 normal subjects of comparable age and gender were also included. We compared αKL protein expression on PBLs by flow cytometry between both groups. Significant reductions in percentages of αKL protein expression on B lymphocytes (CD19), T lymphocytes (CD3), and natural killer cells (CD56) were observed among HD patients compared to controls. We also noticed a significant reduction in the percentages of natural killer cells among HD patients. The present study suggests that decreased αKL expression on PBLs may contribute to the immunocompromised status among HD patients, highlighting the importance of understanding the exact function of αKL protein on immune cells. This may offer a future diagnostic and therapeutic tool to improve the immune response among HD patients.

The effects of aging, sex, and tumor burden on the peripheral blood immune cell profile and absolute counts.

Background: To better assess the peripheral immune status and aid in the early diagnosis and prognosis of tumors, we compared the proportion and absolute counting of peripheral immune cell subsets in healthy individuals and tumor patients of varying ages, taking into account the impact of sex and tumor metastasis. Methods: We used peripheral blood mononuclear cell (PBMC) samples from 520 patients with various tumor types and 109 healthy volunteers. The absolute numbers of lymphocytes and monocytes were identified by an automated blood analyzer, and multi-parameter flow cytometry was used to examine the subsets of natural killer (NK) cells (CD3-CD16+CD56+), T cells (CD3+CD4+/CD8+), and mononuclear cells (CD14+) in PBMC. Results: The percentage of T cells (CD3+) in peripheral blood mononuclear cells (PBMC) was 55.83% VS 45.54% (P<0.0001) between healthy volunteers and tumor patients, showing a significant downward trend. Meanwhile, the percentages of monocytes (CD14+) and NK cells (CD3-CD16+CD56+) showed a significant upward trend. Single factor or multifactor analysis yielded identical findings on the proportion of PBMC between healthy individuals and patients with different malignancies, considering the three confounding variables of age, sex, and tumor metastasis. Conclusion: The proportion and absolute counting of acquired immune T cells, innate immune NK cells, and monocytes in PBMCs all exhibit substantial changes between cancer patients and healthy individuals, and the differences are influenced by age, sex, and tumor progression.

Splenic B Cell Lymphoma Innate Immune Cells: Detection of Red Versus White Pulp Lymphoma Differences in NK Cell Populations By High-Parameter Flow Cytometry

Introduction Splenic B-cell lymphomas, (SLs, total incidence ~1:100,000/year) comprise four distinct indolent B-cell non-Hodgkin lymphomas. Three predominantly involve the red pulp of the spleen (classical hairy cell leukemia (HCL), hairy cell leukemia variant (HCLv) and splenic diffuse red pulp small B-cell lymphoma (SDRPL)) and the fourth predominantly involves the white pulp (splenic marginal zone lymphoma (SMZL)). HCL is usually diagnosed by detection of an activation mutation in BRAF and responds well to treatment. We focused our study on the remaining three diseases, which have overlapping clinical presentations with only subtle differences in their morphology and phenotypes, but have considerable differences in prognosis, response to treatment and outcome. The white pulp lymphoma SMZL generally has good treatment responses and longer survival, whereas the red pulp SLs, HCLv and SDRPL are less responsive to treatments with shorter survival. Cells of the tumor microenvironment (TME) may have distinct characteristics between these three diseases. We hypothesized that TME innate immune cells from red pulp SLs (HCLv, and SDRPL) would be similar to each other and distinct from the white pulp SL, SMZL.In this study, we report that natural killer (NK) cells, which are important innate immune cells critical for immune surveillance, vary in proportions among red and white pulp SLs. Methods We studied splenectomy specimens from patients with SMZL (n=8), HCLv (n=8), SDRPL (n=7), and controls (healthy, post-trauma, n=8). Cryo-preserved bulk splenic suspension cell isolates from fresh (&amp;lt;4 hour) surgical specimens and intact formalin-fixed paraffin embedded (FFPE) tissue sections were used. Human specimen collection and usage was conducted with written informed consent after approval of the Institutional Research Subjects Review Board. FFPE tissue sections were studied by immunohistochemical (IHC) staining and splenic suspension cells were analyzed by high-parameter fluorescence flow cytometry using a Cytek Aurora spectral flow cytometer with a 25-color myeloid and a 28-color NK/B-cell panel. Results IHC characterization showed an extensive network of innate immune cells as reflected by CD163 + macrophages. Using high-parameter flow cytometry, we focused on innate immune cells in the non-B- non-T-cell (CD3 -CD19 -) population. The average proportions of this population were: NK cells 25-36%, monocyte/macrophages 20-34%, dendritic cells 5-11%, and granulocytes 2%. Among the patient groups, the median percentage of NK cells was greater for controls (34%) and SMZL (35%) as compared to red pulp lymphomas (HCLv (28%), SDRPL (24%)). Next, we examined NK subtypes: 1) cytotoxic NK cells (CD56 +CD16 +), 2) cytokine-secreting weakly cytotoxic NK cells (CD56 +CD16 -), and 3) undefined NK cells (CD56 -CD16 +) as a median percentage of total NK cells. The major subtype for control and SMZL was CD56 +CD16 - with values of 58 and 44%, respectively. This subtype comprises only 38%-40% of red pulp SLs. Proportionally the CD56 +CD16 + subtype was the largest for red pulp SLs at 52-57% as compared to 30% for control and 38% for SMZL. The remaining CD56 -CD16 + NK cell subtype was generally higher among red pulp SLs (HCLv (9%), SDRPL (12%)) as compared to control (6%) and SMZL (4%) patients. The increase in cytotoxic CD56 +CD16 + subtype among red pulp SLs was confirmed by measuring the percentage of granzymeB +perforin + cells among mature cytotoxic NK cells (CD56 +CD16 +/ CD57 +NKG2a -). SLs had higher proportions of this NK phenotype (78-86% compared to control 69%) and red pulp SLs had the most granzymeB +perforin + proportions with 82 and 86% for HCLv and SDRPL, respectively. Discussion In summary, spleens from patients with SMZL had similar percentages of total NK cells to controls, with lower percentages in red pulp SLs. All SLs had a higher percentage of cytotoxic NK cells than control, with the red pulp SLs having the most. These data suggest that monoclonal antibody treatments targeting SL antigen, such as anti-CD20, may be effective by activating cytotoxic NK cell to target lymphoma cells by antibody-dependent cellular cytotoxicity. Thus, uncovering the characteristics of the TME may aid the development of non-invasive diagnostic procedures and/or precision therapies.

Determination of Reference Values of Hematopoetic CELLS in Normal BONE Marrow By 10 Colors FLOW Cytometry in Brazilian Population

Purpose: To determine relative and absolute reference values of normality in individuals with no hematologic disease bone marrow, as well as normal patterns of maturation for the different hematopoietic lineages. Methods: Bone marrow samples were collected from 46 healthy patients (16 women and 30 men) undergoing orthopedic surgery and were aged between 18 and 87 years (median 36 years). The analysis of 8 tubes performed in an equipment with 10 colors configuration enabled to evaluate and quantify (% and mm³) B lymphocytes (immature and mature), T lymphocytes (helper, cytotoxic, double negative, double positive), natural killer cells, granulocytes (myeloblasts, promyelocytes, myelocytes, metamyelocytes, rods and neutrophils), monocytes (monoblasts, promonocytes, mature monocytes, classical, intermediate and non-classical), erythroblasts (immature and mature), plasma cells, basophils, mast cells, myeloid dendritic cells and plasmacytoid dendritic cells. The results were evaluated according to sex (female and male), age group (&amp;lt;40, 40 to 60, &amp;gt;60 years), and described as median percentage and absolute values. Results: In evaluating the results according to age group, we identified that older individuals presented an increase in plasma cells that expressed CD56 (p=0.031 in absolute values). In addition, they also had increase relation of CD4/CD8 ratio (p=0.002), mast cells (p=0.004 in percentages), non-classical monocytes (p=0.016 in percentages), as well as a decrease in cytotoxic T lymphocytes (p=0.031 in absolute values), double negative T lymphocytes (p=0.018 in absolute values), and natural killer cells that express CD56 (p =0.002 in absolute values and p=0.012 in percentages). Moreover, these individuals also presented higher natural killer cells that expressed CD56 and CD16 (p=0.024 in absolute values), myeloblasts (p=0.048 in absolute values), metamyelocytes/Rods (p=0.038 in absolute values), neutrophils (p=0.006 in absolute values), monoblasts (p=0.030 in absolute values), mature monocytes (p=0.024 in absolute values), classical monocytes (p=0.017), plasmacytoid dendritic cells (p=0.027 in absolute values), and mature erythroblasts (p=0.004 in absolute values). In the evaluation of the results according to sex, we identified that the population of mature B lymphocytes (p=0.013) and B lymphocytes that expressed CD5 (p=0.014) was higher in women, while the percentage of natural killer cells was relatively higher than in men (p=0.007), particularly in the population of cells that expressed CD56 and CD16 (p=0.013). Conclusion: This study established reference values (absolute and relative) of B lymphocytes (immature and mature), T lymphocytes (helper, cytotoxic, double negative, double positive), natural killer cells, granulocytes (myeloblasts, promyelocytes, myelocytes, metamyelocytes, rods and neutrophils), monocytes (monoblasts, promonocytes, mature monocytes, classical, intermediate and non-classical), erythroblasts (immature and mature), plasma cells, basophils, mast cells, myeloid dendritic cells and plasmacytoid dendritic cells according sex and age group in bone marrow samples from individuals with no hematologic disease Maturational stages of B lymphocytes, granulocytes, monocytes and erythroblasts was shown to be stable regardless of sex and age.

A High Percentage of DNAM-1+ and Low Percentage of Tactile+ NK Cells at Diagnosis Correlate with Complete Response and Survival in AML: A Sub-Analysis of the Ven-a-Qui Pethema Trial

Background: Natural killer (NK) immune status in Acute Myeloid Leukemia (AML) could influence therapeutic results and natural history of the disease. Objectives: In the phase I/II VEN-A-QUI (Clinical trials NCT04687761) clinical trial for unfit newly diagnosed AML patients (venetoclax+Quizartinib+azacytidine or low-dose cytarabine), it was planned a prospective study of NK populations and their influence in the main clinical outcomes. NK cells were analyzed at the diagnosis in a central laboratory. Material and methods: We analyzed NK cell subpopulations based in the expression of DNAM-1, TIGIT, TACTILE, CD8, PD-1, TIM-3, LAG-3, NKp44, NKp46, NKp30, CD16, CD85j,KIR2D, NKG2C, NKG2A, CD57, CD6, CD244, NKp80, Perforin, Granulolysin and Granzyme B. We compare composite Complete Remission (CRc) results of the Venetoclax/Quizatinib with Aza or Cytarabine vs. not achieving CRc using t Student. MaxStat statistics was used to test the significant limit of those populations with a significant difference (R-statistics version 4.2.2). Survival analysis comparing significant differences between patients in CRc was performed using LogRank test and Kaplan Maier. Cox survival analysis was performed to evaluate if the presence of this populations could be an independent factor against the European Leukemia Net classification of 2017 and p53. Data of molecular characteristics were obtained with an NGS panel of 40 genes. RESULTS: The trial included 76 ineligible patients for intensive chemotherapy (37 and 39 were in Aza and LDAC arms respectively). cCR was obtained in 39 patients (51.3%). ELN2017 risk was favorable in 8, intermediate in 15, and Adverse in 53. In 70 patients NK cell populations were analyzed (4 patients with very low percentage of NK cells, 2 with no sample at diagnosis were excluded from the study). There were significant differences between patients who achieve CRc and those who did not, according to DNAM-1 (74.4% vs 61.9, p=0.0018) and TACTILE (62% vs. 72%, p=0.02) expression on NK cells. The rest of antigens analyzed on NK cells were not significant. We found a cutoff of 62% of DNAM-1+ and less than 81% of TACTILE to differentiate populations in terms of survival using long-rank test. The number of DNAM-1 positive was 47 (60%) and TACTILE- was 55 (78%). The median OS of DNAM-1+ was better than DNAM-1− (18.4 vs 4.7 months, p=0.0001), and between TACTILE− vs TACTILE+ (17,36 vs. 4.6 months, p=0.005). Using an Cox model comparing karyotype, p53 and DNAM-1+ and TACTILE-, only DNAM-1+ was associated with better outcome (HR:0.33 (0.17-0.66) and TACTILE+ with worse (HR: 2.44 (1.20-4.99) in multivariate analysis. Conclusions: DNAM-1(CD226) positive and TACTILE (CD96) negative NK cell populations are associated to CR and better OS. These findings need to be confirmed in larger studies. Interestingly, DNAM-1 is an activating receptor and TACTILE is an inhibitory receptor for NK cells that share the same CD155 ligand but display opposite function.

Sicilian Semi- and Supercentenarians: Age-related NK Cell Immunophenotype and Longevity Trait Definition.

The immune system of semi- and supercentenarians (i.e., the oldest centenarians) is believed to have peculiar characteristics that enable them to reach extreme longevity in a relatively healthy state. Therefore, in previous papers, we investigated, through flow cytometry, variations in the percentages of the main subsets of Tαβ and Tγδ cells in a Sicilian cohort of 28 women and 26 men (age range 19-110 years), including 11 long-living individuals (>90 years old) and 8 oldest centenarians. These investigations suggested that some observed immunophenotypic changes may contribute to the extreme longevity of the oldest centenarians. In the present study, to further characterize the immunophenotype of the oldest centenarians, we examined the percentages of Natural Killer (NK) cells identified as CD3-CD56 + CD16+ in the previously described Sicilian cohort. We found a highly significant increase in NK cell percentages with age. When stratified by gender, this significant increase with age was maintained in both sexes, with higher significance observed in males. Our findings on NK cells, together with the previously obtained results, discussed in the context of the literature, suggest that these changes are not unfavourable for centenarians, including the oldest ones, supporting the hypothesis that immune aging should be considered as a differential adaptation rather than a general immune alteration. These adapted immune mechanisms allow the oldest centenarians to successfully adapt to a history of insults and achieve remarkable longevity.

Hepatitis B Virus Envelope Antigen and Hepatitis B Virus Surface Antigen Both Contribute to the Innate Immune Response During Persistent Hepatitis B Virus Infection.

This study aimed to investigate the changes of toll-like receptor 4 (TLR4), proinflammatory cytokine expression, hepatitis B virus surface antigen (HBsAg), and hepatitis B virus envelope antigen (HBeAg) expression as well as innate immune cell percentages in a mouse model of persistent hepatitis B virus (HBV) infection to better understand the innate immune response. Mouse models of persistent HBV infection, HBsAg expression, and HBeAg expression were developed using high-pressure tail-vein injection of recombinant adeno-associated viruses. Enzyme-linked immunosorbent assays (ELISAs) were used to determine the serum proinflammatory cytokine levels. Immunohistochemistry and western blot assays were used to detect TLR4 expression. Flow cytometric analysis was used to assess the percentage of innate immune cells in the whole blood. Persistent HBV infection, HBsAg expression, and HBeAg expression each significantly decreased the expression of TLR4. Persistent HBV infection significantly increased the percentages of T cells and monocytes, whereas it decreased the percentage of natural killer (NK) cells. Persistent HBeAg expression also decreased the percentage of NK cells, whereas persistent HBsAg expression increased the percentage of NK cells. Both persistent HBsAg and HBeAg expression increased the percentage of monocytes. However, both persistent HBsAg and HBeAg expression decreased the percentage of T cells. HBV as well as HBsAg and HBeAg showed similar effects on the expression of TLR4 and proinflammatory cytokines as well as the percentage of monocytes. Persistent HBV infection increased the percentage of T cells and decreased the percentage of NK cells, whereas only persistent HBeAg expression contributed to a decreased percentage of NK cells.

The clinical value of anal swabs for microbial detection in allogeneic haematopoietic stem cell transplantation

The intestinal microbiota plays critical roles in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Rapid and effective microbial detection methods have important guiding value for the selection of intervention strategies for allo-HSCT recipients. We evaluated the application of the anal swab test before transplantation in allo-HSCT recipients. A total of 120 patients who underwent anal swab testing before allo-HSCT were retrospectively analyzed and divided into 3 groups: sterile (aseptic growth-negative), G+ (gram-positive bacterial colonization), and G- (gram-negative bacterial colonization). On 16S rRNA sequencing, gram-negative bacteria predominated in the G- group before and after transplantation. Compared with the sterile group, the percentage of natural killer cells was higher and the percentage of T cells was lower after transplantation in the G- group at 1 month after transplantation. The percentage of CD4+ and CD4+CD8+ T cells was lower and the percentage of regulatory T cells was higher in the G- group. The plasma levels of proinflammatory cytokines (TNF-α, IFN-γ, IL-6, and IL-17A) at 2 weeks post-transplantation were lower in the G- group than in the sterile group, as was the cumulative incidence of grade III-IV acute graft-versus-host disease (GVHD). Gram-negative bacterial colonization before allo-HSCT was associated with low rates of bloodstream infections within 100 days post-transplantation and cytomegalovirus reactivation at 100 days to 2 years post-transplantation. Moreover, patients in the G- group had a higher rate of 2-year GVHD-free, relapse-free survival compared with patients in the sterile group. The detection results using anal swabs were consistent with the gram-negative or gram-positive bacteria abundance of 16S rRNA sequencing results and associated with immune homeostasis and clinical outcomes after allo-HSCT. Anal swab testing may have potential advantages as a simple and effective method for microbial detection in allo-HSCT.

Evaluation of immunotoxicity of sodium metavanadate following drinking water exposure in female B6C3F1/N mice in a 28-day study.

Sodium metavanadate (NaVO3 ) is a pentavalent vanadium compound used in the metal industry and dietary supplements; human exposure occurs through inhalation of fumes and dust and ingestion of NaVO3 -containing products. The objective of this study was to assess the potential immunotoxicity of NaVO3 . Female B6C3F1/N mice were exposed to 0-500 ppm NaVO3 in drinking water for 28 days and evaluated for effects on immune cell populations and innate, cellular-mediated, and humoral-mediated immunity. There was a decreasing trend in body weight (BW) and BW gain in NaVO3 exposed mice, with a decrease (p ≤ 0.05) in BW gain at ≥250 ppm, relative to control. Conversely, increasing trends in spleen weights and an increase (p ≤ 0.05) in the spleen:BW ratio at ≥250 ppm NaVO3 were observed. NaVO3 exposure altered antibody production against sheep red blood cells (SRBC). Antibody forming cells (AFC)/106 spleen cells exhibited a decreasing trend, with a decrease (p ≤ 0.05) at 500 ppm NaVO3 , concurrent with an increase in percent B cells. NaVO3 had no effect on the serum anti-SRBC IgM antibody titers or anti-keyhole limpet hemocyanin antibody production. Exposure to NaVO3 decreased the percentage of natural killer cells at all dose levels (p ≤ 0.05), with no effect on the lytic activity. NaVO3 altered T-cell populations at 500 ppm but had no effect on T-cell proliferative responses or the lytic activity of cytotoxic T cells. Collectively, these data indicate that NaVO3 exposure can adversely affect the immune system by inducing alterations in humoral-mediated immunity, specifically the AFC response, with no effect on cell-mediated or innate immunity.

High levels of NK Cells in graft are associated with reduced febrile neutropenia after haploidentical peripheral blood stem cell transplantation.

To investigate the impact of natural killer (NK) cells in the graft on the outcome following haploidentical peripheral blood stem cell transplantation (haplo-PBSCT). We retrospectively collected data from patients who had undergone haplo-PBSCT at our centre from January 2019 to November 2021. The percentage of NK cells in stem cell grafts was detected by flow cytometry. Based on the median (range) count of NK cells (1.8 [0.4-6.0] × 108/kg), patients were separated into high and low NK cell count groups. Data from 96 patients were analysed. Patients were evenly distributed (48 in each group) into high and low NK cell count groups. There was no significant difference in neutrophil and platelet recovery between the two groups. However, the rates of febrile neutropenia, bacterial infection, and invasive fungal disease (IFD) were significantly reduced in the high compared with the low NK cell count group. There was no significant difference in rates of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections between groups. There was no significant difference between groups in grades II and above acute graft versus host disease (GVHD), progression-free survival (PFS), or overall survival (OS). A high number of NK cells in the graft may reduce febrile neutropenia, IFD and bacterial infection following haplo-PBSCT but it has no significant effect on aGVHD, PFS, or OS.