Percentage Of Dendritic Cells Research Articles

Changes in immune subsets during chemotherapy as prognosis biomarkers for multiple myeloma patients by longitudinal monitoring.

Multiple myeloma (MM) is a malignancy of plasma cells accompanied by immune dysfunction. This study aimed to provide a comprehensive and dynamic characterization of the peripheral immune environment in MM patients and find its diagnostic and prognostic values for therapy. The peripheral immune profiles of MM inpatients and healthy controls were assessed by flow cytometry. A longitudinal study of immune subsets was observed during cycles of chemotherapy. The diagnostic and prognostic models were established based on immune subsets by the absolute shrinkage and selection operator (LASSO) and multivariate regression. MM patients possessed an impeded immune landscape, including reduced activation of B cells, increased effective T cells and regulatory T cells (Tregs), augmented CD16 expression on monocytes and dendritic cell percentages, decreased CD56dimCD16+ natural killer cells (NKs), and amplified CD56bright and HLA-DR+ natural killer T cells (NKTs). Chemotherapy has different dynamic effects on specific cells, of which 2 cycles is the key turning point. NKT, dendritic cells, naïve Tc and Th cells, HLA-DR+ Tc cells, CD56dim NKTs, CD16++ monocytes, and CD25+ B cells could have the diagnostic value, and a prognostic model including neutrophils, naïve Tc cells, CD56brightCD16dim NKs, and CD16+ dendritic cells was established with acceptable accuracy. Our data showed dynamic and abnormal peripheral immune profiles in MM patients, which had prognostic values and could provide the basis for clinical therapy.

Overexpression of ubiquitin-conjugating enzyme 2T induces radiotherapy resistance in hepatocellular carcinoma by enriching regulatory T cells in the tumor microenvironment

To investigate the effect of overexpression of ubiquitin-conjugating enzyme 2T (UBE2T) on radiosensitivity of hepatocellular carcinoma (HCC). Hepa1-6 cells were transfected with a UBE2T-overexpressing or a control lentiviral vector, and the changes in their radiotherapy sensitivity and concentrations of glucose and lactate in the supernatant were assessed using colony-forming assay and colorimetric assay. The transfected cells were inoculated subcutaneously in nude mice or C57BL/6 mice, and tumor growth following irradiation were recorded. The xenografts were collected for analyzing infiltration of CD4+ T cells and regulatory T cells (Tregs) using flow cytometry and detecting expressions of HK1 and LDHA using Western blotting. The correlations of UBE2T expression with immune cell infiltration, glycolysis and Tregs in HCC were analyzed using CIBERSORT algorithm and TCGA database, and the results were verified in a co-culture system of Hepa1-6 cells and Tregs. UBE2T overexpression caused radiotherapy resistance in both cultured Hepa1-6 cells and xenografts in the tumor-bearing mouse models (especially in C57BL/6 mice). CIBERSORT analysis suggested that a high expression of UBE2T was associated with increased percentages of dendritic cells, T follicular helper cells, M2 macrophages, monocytes, lymphocytes and Tregs in HCC. The UBE2T-overexpressing xenografts showed an increased percentage of Tregs and enhanced expressions of HK1 and LDHA, and irradiation increased infiltration of CD4+ T cells and Tregs in the tumor microenvironment. Hepa1-6 cells overexpressing UBE2T showed a decreased glucose concentration and an increased lactate concentration. GSEA analysis suggested that a high UBE2T expression was positively correlated with increased glycolysis and Tregs infiltration in HCC. In the cell co-culture system, UBE2T overexpression significantly enhanced lactate production, proliferation and immunosuppressive functions of Tregs. A high UBE2T expression results in radiotherapy resistance of HCC possibly by enhancing glycolysis and cause enrichment of Tregs in the tumor microenvironment.

Evidence for effect modification by serum clusterin on dendritic cells in association with dementia

AbstractBackgroundAlzheimer’s disease (AD) and AD related dementias (ADRD) are complex heterogeneous diseases with multiple pathogenic mechanisms. Previous experimental studies showed that serum clusterin has a significant role in the maturation of dendritic cells (DCs). Studies showed that myeloid DCs (mDCs) in blood were dysregulated in AD and higher levels of serum clusterin related to higher incidence of dementia. We evaluated the association of DCs in peripheral blood and serum clusterin and their interaction with AD/ADRD.MethodWe used data from 3072 participants in the Health and Retirement Study (HRS) who participated in the 2016 Venous Blood Study (VBS), and had flow cytometry, clusterin and cognition assessed. We used generalized survey logit models to evaluate the association between the DCs, clusterin, and dementia after adjusting for age, sex, race, education, comorbidity, body mass index (BMI) and Cytomegalovirus (CMV) seroprevalence. Utilizing the RNAseq data, we performed differential gene expression (DGE) analysis on DCs, clusterin and dementia to identify overlapping genes in the biological process.ResultWe found that after covariate adjustment, a higher percentage of dendritic cells was associated with lower odds of having dementia (OR = 0.61, 95% CI: [0.44, 0.86]; p = 0.005). We found that higher levels of serum clusterin was associated with higher odds of having dementia. This relationship was somewhat attenuated after covariate adjustment (OR = 1.07, 95% CI [0.99, 1.16], p = 0.09). We found a significant interaction between serum clusterin and DCs in the association with dementia (p = 0.02) with those having low DCs and high clusterin being at increased ADRD risk (OR = 1.25) and those with high DCs and low clusterin being at lower ADRD risk (OR = 0.48) as compared to those who have both low DCs and low clusterin. We identified three genes (TUBB4A, WASHC5 and GSTA4) that were dysregulated in the pathways of DCs and clusterin in association with dementia.ConclusionThis study has shown, for the first time, an interaction between serum clusterin and DCs in peripheral blood that is associated with increased risk of dementia in a large sample of older adults that needs to be validated in future studies.

A biologic-device combination product delivering tumor-derived antigens elicits immunogenic cell death-associated immune responses against glioblastoma

BackgroundIGV-001 is a personalized, autologous cancer cell-based immunotherapy conceived to deliver a tumor-derived antigenic payload in the context of immunostimulatory signals to patients with glioblastoma (GBM). IGV-001 consists of patient-derived...

Introduction of E-Score: A gene expression score to characterize immunogenic versus oncogenic HPV expression in HNSCC.

6057 Background: Human Papillomavirus (HPV) integration in the human genome occurs in a majority of HPV(+) head and neck squamous cell carcinomas (HNSCC), with direct and indirect effects on host gene expression and tumorigenesis. Although previous studies showed that HPV integration in HNSCC is overrepresented in genes often somatically mutated in head and neck, lung, and urogenital cancers, reports are mixed for whether patients with HPV integration have worse clinical outcomes. These disparate results may be due to differences in how integration is defined. Integration can often lead to partial loss of the viral genome (e.g. HPV genes E1, E2, or E5) with retention of the oncogenes E6 and E7, which led to a low E2/E7 expression ratio being used as a biomarker for integration. Conversely, others have used the direct detection of DNA or RNA HPV-human breakpoints to identify tumors harboring integrated HPV. HPV integration and the retention or deletion of HPV genes can dramatically change the expression of HPV genes, and we hypothesize it also affects the host immune response. Hypothesis: Loss of non-oncogenic HPV genes relative to E6 and E7 levels reduces immunogenicity, leading to weakened immune cell infiltration and worse clinical outcomes. Methods: Bulk RNA sequencing data from HPV(+) HNSCC tumors (n = 136) was used to characterize the differences in retention or loss of HPV genes and calculate the E-Score as the sum of the logCPM of HPV genes E1, E2, E4, and E5 relative to E7. Cell type deconvolution was performed using ComBat to correct for batch effects, and CIBERSORTx to quantify cell type proportions within the tumor samples. Kaplan-Meier estimates of recurrence and overall survival (OS) were calculated, and Cox proportional hazards tests with covariates were used to test for association with recurrence and OS. To test the correlation between immune cell type inferred proportions and E-Score, T-Tests were performed between samples with high and low E-scores. Results: Low E-Score was significantly associated with recurrence (p = 0.012) but not with OS (p = 0.39) in the multivariate model accounting for age, tumor stage (AJCC8), smoking status, drinking status, BMI, marital status, and molecular tumor subtype (defined as IMU or KRT). For integration positive samples (n = 66), higher E-Score, suggesting lower rates of HPV gene loss, was correlated with higher percentages of dendritic cells (p = 0.044), macrophages (p = 0.021), and CD8+ T Cells (p = 0.024), but not CD4+ T cells (p = 0.14). This significance did not hold when looking at integration negative samples. Conclusions: These results suggest that HPV+ HNSCC patients with a loss of E1, E2, E4 and E5 tend to have less immune cell infiltration and are more likely to have recurrence. We conclude that E-Score is a potential prognostic biomarker of recurrence in HPV+ HNSCC and potential predictive biomarker for immunotherapy.

Modulating T cell inflammation in a mouse model of Alzheimer’s disease

AbstractBackgroundRecent single cell transcriptomic studies using peripheral blood and post‐mortem brain samples from Alzheimer’s disease (AD) patients have suggested a significant role for T cells in modulating AD‐related neuroinflammation. Previous findings from our group and others show that T cells in AD patients and aged individuals are clonally expanded and upregulate genes related to inflammation, cytotoxicity, and senescence. We have found that TSC22D3, a putative anti‐inflammatory transcription factor, is upregulated in brain‐infiltrating CD8+ T cells and found in gene co‐expression modules in peripheral blood from AD patients.MethodWe are pursuing the mechanism of TSC22D3 function and its effect on T cell biology and AD neuropathology. We have generated mice that lack TSC22D3 in CD8 T cells on the 5XFAD background, a mouse model of AD. We used flow cytometry to measure populations of various immune cell subtypes, and sort T cell subtypes for downstream sequencing. We are also using immunocytochemistry to quantify markers of amyloid and tau pathology, microglial interaction with amyloid plaque, and neuronal and synaptic loss in the hippocampus. Finally, we are examining the induction of immune reactions to amyloid and tau protein in TSC22D3 conditional knockout mice without AD transgenes.ResultIn human tissue, TSC22D3 is highly expressed in brain‐infiltrating CD8+ T cells along with genes associated with a senescent, late‐differentiation phenotype. Flow cytometry analysis showed that late‐stage AD mouse splenocytes bore significantly higher percentages of dendritic cells and various cytokines in CD4+ T cells than non‐AD or younger AD mice. Most of these differences were independent of TSC22D3 conditional knockout status. Ongoing bulk sequencing may reveal TSC22D3‐dependent changes in T cell gene expression, with effects on key markers of AD progression in the hippocampus.ConclusionTSC22D3 is known to directly suppress NFkB and other pro‐inflammatory mediators. Its co‐expression with more pro‐inflammatory and cytotoxic genes in brain‐infiltrating CD8+ T cells may represent a compensatory mechanism in the face of neuroinflammation related to aging and AD. We expect that knockout of TSC22D3 in CD8+ T cells will increase expression of pro‐inflammatory genes in T cell subsets, and will manifest in advanced AD pathology in older adult mice.

Voluntary Wheel Running Reduces Hepatic Dendritic And Cytotoxic T Cells In Western Diet-fed C57Bl/6 J Mice

The activation of innate immunity and recruitment of infiltrating macrophages are critical components of non-alcoholic steatohepatitis (NASH). In mice, voluntary wheel running (VWR) has improved hepatic steatosis and markers of inflammation; however, few studies have evaluated the effects of VWR on hepatic macrophages and hepatic immune cells linked to the development of NASH. PURPOSE: To determine the preventative effects of voluntary wheel running on hepatic macrophages and hepatic immune cells in mice fed a Western diet for 18 weeks. METHODS: Male, 8-week old, C57Bl/6 J mice (n = 56; 14/group) were randomly assigned to either a normal diet (ND) or Western diet (WD; 45% lard, 17% fructose, 0.75% cholesterol), followed by again randomly dividing each dietary group into either a sedentary (SED) or VWR group. Following 18-weeks, the relative percentage of hepatic macrophages (F4/80intCD11b+Ly6C- Kupffer cell, F4/80intCD11b+Ly6C+ infiltrating macrophage, and F4/80+CD11b+CD11c+ dendritic cell) and hepatic immune cells (CD45+CD19+ B-cell, CD45+CD4+ T-cell, and CD45+CD8+ cytotoxic T-cell) were isolated and cell populations were identified by flow cytometry. Differences between the four groups (ND + SED, ND + VWR, WD + SED, and WD + VWR) were identified by one-way ANOVA. RESULTS: No significant differences in either macrophage or immune cell populations were observed between ND + SED and ND + VWR. When compared to ND + SED, WD + SED had significantly (p < 0.05) higher percentage of cytotoxic T-cells (3.4 ± 0.5% vs. 8.2 ± 1.9%), dendritic cells (2.1 ± 0.4% vs. 8.6 ± 2.0%), and infiltrating macrophages (0.6 ± 0.5% vs. 1.6 ± 1.9%). In contrast, WD + VWR had lower percentages of cytotoxic T-cells (3.9 ± 0.5%) and dendritic cells (5.4 ± 1.1%) such that the percentage of cells were not significantly different than ND + SED and ND + VWR. Infiltrating macrophages remained relatively unchanged (1.4 ± 0.2%) in WD + VWR. Despite the positive changes in WD + VWR, the percentage of cytotoxic T-cells (p = 0.056) and dendritic cells (p = 0.387) were not significantly different than WD + SED mice. CONCLUSIONS: In mice fed a Western diet for 18 weeks, voluntary wheel running reduced the relative percentage of dendritic cells and cytotoxic T cells in the liver. Supported by SIUE Seed Grants for Transitional and Exploratory Projects.

Detection of Specific Immune Cell Subpopulation Changes Associated with Systemic Immune Inflammation-Index Level in Germ Cell Tumors.

The tumor microenvironment (TME) and the host inflammatory response are closely interconnected. The interplay between systemic inflammation and the local immune response may influence tumor development and progression in various types of cancer. The systemic immune–inflammation index (SII) represents a prognostic marker for germ cell tumors (GCTs). The aim of the present study was to detect specific immune cell subpopulation changes which were associated with the SII level in chemotherapy-naïve GCT patients. In total, 51 GCT patients, prior to cisplatin-based chemotherapy, were included in the present study. Immunophenotyping of peripheral blood leukocyte subpopulations was performed using flow cytometry. The SII level was correlated with the percentage of various leukocyte subpopulations. The obtained results demonstrated that SII levels above the cut-off value of SII ≥ 1003 were associated with higher neutrophil percentages. An inverse correlation was found between the SII and the peripheral lymphocyte percentage that logically reflects the calculations of the SII index. Furthermore, the presented data also showed that in the lymphocyte subpopulation, the association with the SII was driven by T-cell subpopulations. In innate immunity–cell subpopulations, we observed a correlation between SII level and neutrophils as well as associations with eosinophil, basophil, natural killer cell and dendritic cell percentages. We suppose that the described interactions represent a manifestation of cancer-induced immune suppression. The results of the present study contribute to the elucidation of the interrelationship between tumor cells and the innate/adaptive immune system of the host.

Identification of Similarities Between Skin Lesions in Patients With Antisynthetase Syndrome and Skin Lesions in Patients With Dermatomyositis by Highly Multiplexed Imaging Mass Cytometry.

Antisynthetase syndrome (ASyS) and dermatomyositis (DM) are autoimmune disorders that overlap clinically. Given the presence of DM-like skin lesions in ASyS patients, there is debate about whether ASyS is a distinct disease or a subclassification of DM. Recent studies identified differences in type I interferon (IFN) expression between ASyS and DM muscle and finger eruptions. This study was undertaken to elucidate similarities and differences in the pathogenesis of cutaneous disease in ASyS and DM at the single-cell level. Five ASyS patients and 7 DM patients were recruited from a prospectively collected database of well-characterized DM patients. ASyS patients were clinically confirmed as having ASyS according to the Connors et al criteria and the Solomon et al criteria and the presence of aminoacyl-transfer RNA synthetase antibodies. Immunophenotyping was conducted using immunofluorescence (IF) and imaging mass cytometry (IMC). IF staining for MxA and IFNβ expression revealed up-regulation of type I IFN in ASyS and DM samples compared to healthy control samples (P < 0.05). IMC showed similar numbers of macrophages, T cells, B cells, and dendritic cells in ASyS and DM samples, with no differences in counts (P > 0.05), but an increase in myeloid dendritic cell percentage in DM samples (P < 0.05). Key type I IFN, cytokine, and JAK/STAT pathways were similarly expressed in both ASyS and DM (P > 0.05). At the single-cell level, macrophages positive for phosphorylated stimulator of IFN genes in ASyS samples expressed increased levels of tumor necrosis factor, interluekin-17 (IL-17), and IFNβ (P < 0.001). IMC is a powerful tool that identifies a role for the type I IFN system in DM-like skin lesions in ASyS and DM with some differences at the cellular level, but overall significant overlap, supporting similar therapeutic decision making.

Interaction of Human Dendritic Cells with Graphene Oxide Nanoparticles In Vitro.

We studied the effect of graphene oxide nanoparticles on the differentiation of human dendritic cells and uptake of nanoparticles by these cells in vitro. The objects of the study were mononuclear cells from healthy donors induced into the phenotype of dendritic cells by cytokines (IL-6 and GM-CSF). We used graphene oxide nanoparticles of different sizes functionalized with linear or branched PEG (P-GO or bP-GO) in concentrations of 5 and 25 μg/ml. It was found that graphene oxide nanoparticles did not affect the viability and percentage of dendritic cells in the culture. However, P-GO nanoparticles (25 μg/ml) suppressed the expression of CD83 on the surface of dendritic cells in cultures, thereby suppressing cell differentiation. Dendritic cells internalized P-GO nanoparticles, particles in high concentration were more actively engulfed, but the size of the particles and the type of PEG did not affect the intensity of this process. In general, P-GO nanoparticles in a concentration of 25 μg/ml can regulate differentiation of dendritic cells by suppressing their maturation.

Abstract PO067: The immune cell infiltration and landscape predicts clinical outcomes in gynecologic cancers

Abstract Introduction: Immunotherapy has changed the standard of treatment for many cancers. However, only a small number of gynecologic cancer patients benefit from immunotherapy. The intratumoral immune landscapes are suggested as a predictor of the response to immunotherapies. However, there are no studies that provide a comprehensive immune characterization for gynecologic cancers. Aims: To characterize cellular compositions of the immune infiltrates and investigate if the immune landscape is a predictor for patient prognosis in gynecologic cancers. Methods: Clinical data for ovarian cancer, cervical cancer, and uterine cancer were downloaded via TCGA. RNA data are download from http://gdac.broadinstitute.org. Immune cell infiltration was analyzed using QuanTIseq and EPIC. Immune subtype clusters of patients were identified by Graph-based consensus clustering. Statistical analysis was conducted by GraphPad Prism. Results: Ovarian cancer had the highest percentage of total immune cells (approximately 21%, including CD4 T-Cells, Monocytes, CD8 T-Cells, Dendritic Cells, Macrophages, Neutrophils, NK Cells, B-Cells). Cervical cancer and uterine corpus endometrial carcinoma have lower percentages of immune cells with 17% and 16%, respectively. Furthermore, ovarian cancer had a significantly higher Monocyte and M2-liked Macrophage percentage, but lower percentage for CD8 T cells and Neutrophils compared to cervical cancer and uterine cancer. Cervical cancer had the highest percentage for M1-liked Macrophages and lowest CD4 T cells. Uterine cancer had the highest percentage of dendritic cells. In cervical cancer, higher cell infiltration of CD8 T-Cells and M2-liked Macrophages was associated with a better prognosis. In uterine cancer, patients with higher number of dendritic cells and CD8 T-Cells had significantly better clinical outcomes. However, higher CD4 T-cell infiltration was associated with poor prognosis in uterine cancer. Interestingly, patient’s survival was not affected by the infiltration of any individual immune cells which we analyzed in ovarian cancer. We identified and validated four immune subtypes associated with distinct immune cell infiltration in gynecologic cancers. Cervical and uterine cancer patients from an immune-desert subtype that had the least amount of lymphocyte infiltration and a high level of Monocyte had the worst prognosis. By contrast, Cervical and uterine cancer patients from an immune-warm subtype that had higher infiltration of CD8 T-cell, NK Cell, and dendritic cells had the best prognosis. However, the survival rate of ovarian cancer patients is similar among four different subtypes. Conclusion: Our study provides a conceptual framework to understand the tumor immune microenvironment of different gynecologic cancers. This work also suggests that the immune microenvironment should be considered for the design of combination treatment strategies and guiding the optimal selection of patients for immunotherapy. Citation Format: Wai Chung Chen, Tuo Hu, Chunbo He. The immune cell infiltration and landscape predicts clinical outcomes in gynecologic cancers [abstract]. In: Abstracts: AACR Virtual Special Conference: Tumor Immunology and Immunotherapy; 2020 Oct 19-20. Philadelphia (PA): AACR; Cancer Immunol Res 2021;9(2 Suppl):Abstract nr PO067.

Inhibition of MDM2 Promotes Antitumor Responses in p53 Wild-Type Cancer Cells through Their Interaction with the Immune and Stromal Microenvironment.

p53 is a transcription factor that plays a central role in guarding the genomic stability of cells through cell-cycle arrest or induction of apoptosis. However, the effects of p53 in antitumor immunity are poorly understood. To investigate the role of p53 in controlling tumor-immune cell cross-talk, we studied murine syngeneic models treated with HDM201, a potent and selective second-generation MDM2 inhibitor. In response to HDM201 treatment, the percentage of dendritic cells increased, including the CD103+ antigen cross-presenting subset. Furthermore, HDM201 increased the percentage of Tbet+Eomes+ CD8+ T cells and the CD8+/Treg ratio within the tumor. These immunophenotypic changes were eliminated with the knockout of p53 in tumor cells. Enhanced expression of CD80 on tumor cells was observed in vitro and in vivo, which coincided with T-cell-mediated tumor cell killing. Combining HDM201 with PD-1 or PD-L1 blockade increased the number of complete tumor regressions. Responding mice developed durable, antigen-specific memory T cells and rejected subsequent tumor implantation. Importantly, antitumor activity of HDM201 in combination with PD-1/PD-L1 blockade was abrogated in p53-mutated and knockout syngeneic tumor models, indicating the effect of HDM201 on the tumor is required for triggering antitumor immunity. Taken together, these results demonstrate that MDM2 inhibition triggers adaptive immunity, which is further enhanced by blockade of PD-1/PD-L1 pathway, thereby providing a rationale for combining MDM2 inhibitors and checkpoint blocking antibodies in patients with wild-type p53 tumors. SIGNIFICANCE: This study provides a mechanistic rationale for combining checkpoint blockade immunotherapy with MDM2 inhibitors in patients with wild-type p53 tumors.

The unique characteristic in peripheral immune cells in patients with advanced hepatocellular carcinoma

Recent progress in cancer immunology provides more insight in immune evasion of cancer cells. Cancer cells may achieve immune evasion through several ways including ineffective antigen presentation, T cell checkpoint utilization, immunosuppressive cytokines secretion and immunosuppressive cells recruitment. However, few literatures mentioned about the change of peripheral blood immune cells in advanced hepatocellular carcinoma (HCC) patients. To answer this question, we initiated a pilot study through detailed flow cytometry. We enrolled patients with advanced HCC patients who had informed consent to the collection of their peripheral blood. We also recruited healthy individuals for the control group. Using flow cytometry, we analyzed lymphocyte subclasses and the PD-1 or PD-L1 positivity of immune cells in peripheral blood from HCC patients and healthy individuals. Twenty-four HCC patients were enrolled and twenty healthy individuals were enrolled. Most of the HCC patients were HBV carrier (58.3%), and the mean age was 61 years old. Among 55 immune cell parameters we examined in peripheral blood, 16 were significantly different between advanced HCC patients and healthy individuals by univariate analysis. Multivariate analysis was then conducted by fitting logistic regression model and showed that CD69-CD25- Naïve CD4αβT cell percentage and dendritic cell percentage can reasonably predict the advanced HCC status from peripheral blood. By our regression model, the adjusted generalized R2=0.918 and the estimated area under the Receiver Operating Characteristic (ROC) curve was 0.99. CD69-CD25- Naïve CD4αβT cell percentage and dendritic cell percentage in peripheral blood are highly correlated with the advanced HCC status. The change may result from immune evasion initiated by hepatocellular carcinoma cells and further investigation is warranted. Validation study is ongoing and this mechanism may be utilized to treat advanced HCC patient in the future.

Degenerative joint changes following intra-articular fracture are more severe in mice with T cell deficiency.

The inflammatory response to joint injury, specifically intra-articular fracture, has been implicated in posttraumatic arthritis development. However, the role of T cells in regulating the development of posttraumatic arthritis is unclear. We hypothesized that the absence of T cells would lead to less severe posttraumatic arthritis following intra-articular fracture. T cell-deficient, athymic nude, and wild-type C57BL/6NJ mice were assessed at 8 weeks following closed articular fracture. Joints were assessed using histologic scores of arthritis, synovitis, and bone morphology via micro computed tomography. Cells were profiled in whole blood via flow cytometry, and plasma and synovial fluid derived cytokines were quantified by multiplex analysis. Compared to C57BL/6NJ mice, nude mice had significantly greater histologic evidence of arthritis and synovitis. Whole blood immune cell profiling revealed a lower percentage of dendritic cells but increased natural killer (NK) cells in nude mice. Concurrently, nude mice had significantly higher levels of NK cells in synovial tissue. Concentrations of plasma interleukin 1β (IL-1β) and tumor necrosis factor α, and synovial fluid IL-12, IL-17, and IL-6 in both knees were greater in nude mice. Outcomes of this study suggest that T cells may play a protective regulatory role against the development of posttraumatic arthritis. Clinical significance: Lack of functional T cells exacerbated the development of posttraumatic arthritis following intra-articular fracture suggesting that critical regulators of the immune responses, contained within the T cell population, are required for protection. Future research identifying the specific T cell subsets responsible for modulating disease immunopathogenesis will lead to new therapeutic targets to mitigate posttraumatic arthritis.

Association Between Circulating Plasmacytoid Dendritic Cell Percentage and Blood Lead Levels in Children.

Lead (Pb) exposure is known to cause T helper 1 (Th1) to T helper 2 (Th2) shift in the immune response. The mechanism responsible for these effects is unclear. Plasmacytoid dendritic cells (pDCs) are known as the principal secretor of type 1 interferons (IFNs), which have a stimulatory effect on Th1 differentiation. However, no previous study has explored the effect of Pb on pDCs. Thus, the present study was conducted to explore the correlation between circulating pDC count, serum IFNα (pan) levels, and blood lead levels (BLLs) in children environmentally exposed to Pb. A total of 82 school-going children were recruited from government and private schools in Jodhpur. BLL, pDC percentages, and serum IFNα (pan) levels were estimated by atomic absorption spectrometry, flow cytometry, and ELISA, respectively, in 82 samples. The participants were divided as per BLL quartiles into 4 groups: (A) BLL < 3 μg/dL (n = 21), (B) BLL = 3-4.08 μg/dL (n = 20), (C) BLL = 4.08-6.17 μg/dL (n = 20), and (D) BLL > 6.17 μg/dL (n = 21). Only in category D, pDC percentages showed a significant positive correlation with BLL (Spearman's R = 0.5). Therefore, this preliminary data suggests that BLL might modulate pDC levels in a dose-dependent manner.

Lignin nanoparticles as a promising vaccine adjuvant and delivery system for ovalbumin

Vaccination is the most effective strategy of preventing and treating infectious diseases and the most significant issue in the development of potent vaccines is the sufficient immunogenicity and safety of vaccines. The main goal of the present study is to develop a potent and safe vaccine adjuvant that can also stabilize antigen formulations during preparation and storage. In this study, the model antigen ovalbumin (OVA) was encapsulated in polymeric nanoparticles based on lignin (OVA-LNPs). The nanoparticles had a particle size of 216 nm and a low polydispersity index. The nanoparticles were negatively charged (−26.7 mV) with high encapsulation efficiency 81.6% of OVA antigen. In vitro studies of the nanoparticles were tested against dendritic cells (DCs), specialized antigen-presenting cells (APCs). The results showed no cytotoxic effect from LNPs and a significantly higher percentage of dendritic cells have taken up the antigen when encapsulated inside LNPs in contrast to free OVA. The nanoparticle was administered intradermally to BALB/c mice and the resulting time-dependent systemic immune responses towards OVA were assessed by measuring the OVA-specific IgG titers using an enzyme-linked immunosorbent assay (ELISA). In vivo immunization with OVA-LNPs induced a stronger IgG antibody response than that induced by free OVA or alum adjuvanted OVA. Enhanced immunization by OVA-LNPs was attributed to the observed efficient uptake of the antigen by dendritic cells. These findings demonstrate that LNPs are promising to be used as vaccine adjuvant and delivery system for the induction of long-term immune responses.

MiR-128 Regulates Tumor Cell CD47 Expression and Promotes Anti-tumor Immunity in Pancreatic Cancer.

Pancreatic adenocarcinoma (PDAC) is a highly fatal disease worldwide. MicroRNAs (miRNAs) could regulate the protein-coding RNAs related to tumor growth, invasion, and immune evasion. Therefore, the investigation of novel miRNAs may be helpful in the development of more effective therapies for PDAC. In this study, we investigated the role and mechanism of action of miR-128 in PDAC. By using bioinformatics methods, we found that decreased expression of miR-128 was associated with poor overall survival of PDAC. miR-128 was inversely correlated with cluster of differentiation 47 (CD47), which was positively related to zinc finger E-box-binding homeobox 1 (ZEB1) in PDAC. Through in vivo experiments, we found that miR-128 could suppress the growth and metastasis of PDAC. Analysis of the immune microenvironment demonstrated that overexpression of miR-128 on tumor cells could increase the percentages of dendritic cells (DCs), CD8+ T lymphocytes, and natural killer T cells (NKT) in the tumor and spleen, consequently enhancing anti-tumor immunity. In vitro assays showed that miR-128 could inhibit cell proliferation, clonogenicity, migration, and invasion in Panc02 cells and could also enhance the phagocytosis of macrophages and the activity of DCs. Western blot and qRT-PCR confirmed that miR-128 could regulate ZEB1 and further inhibit CD47 in pancreatic cancer cells. Therefore, we identified a novel regulatory anti-tumor mechanism by miR-128 in PDAC, which may serve as a novel therapy for PDAC.

Altered Frequency of NK Cells and Treg Cells by Astragalus Polysaccharide Combined with Budesonide in Asthma Model Mice

Objective. We investigated the efficacy of astragalus polysaccharide (APS) combined with budesonide and the effect on expressions of peripheral NK cells and Treg cells and the molecular mechanism in mice with bronchial asthma. Methods. In this study, we established a mouse model of asthma. Four groups of BaLB/C mice were developed; control group had no asthma induction, and the other three groups of mice were sensitized by OVA (Ovalbumin), OVA + budesonide, and OVA + APS + budesonide. Flow cytometry was used to determine the proportion of NK cells and Treg cells. Levels of cytokines IL-4 and IL-10 were detected using RT-PCR and ELISA. Results. Asthma mice treated with APS + budesonide showed alleviated airway resistance compared to model mice (P&lt;0.05). The percentage of dendritic cells (DCs) was reduced (P&lt;0.05), while anti-inflammatory NK cells and Treg cells significantly increased after APS + budesonide treatment (P&lt;0.05). Further, APS + budesonide treatment resulted in improvements in IL-4 and IL-10 mRNA and protein levels (P&lt;0.05). Conclusion. APS combined with budesonide medication may regulate expressions of DCs cells and related cytokines, reliving clinical symptom of bronchial asthma.

Effects of Regulatory T Cell Depletion on NK Cell Responses against Listeria monocytogenes in Feline Immunodeficiency Virus Infected Cats.

Regulatory T cells (Treg) are key players in the maintenance of peripheral tolerance, preventing autoimmune diseases and restraining chronic inflammatory diseases. Evidence suggests Treg cells and NK cells have important roles in feline immunodeficiency virus (FIV) pathogenesis; however, in vivo studies investigating the interplay between these two cell populations are lacking. We previously described innate immune defects in FIV-infected cats characterized by cytokine deficits and impaired natural killer cell (NK) and NK T cell (NKT) functions. In this study, we investigated whether in vivo Treg depletion by treatment with an anti-feline CD25 monoclonal antibody would improve the innate immune response against subcutaneous challenge with Listeria monocytogenes (Lm). Treg depletion resulted in an increased overall number of cells in Lm-draining lymph nodes and increased proliferation of NK and NKT cells in FIV-infected cats. Treg depletion did not normalize expression of perforin or granzyme A by NK and NKT cells, nor did Treg depletion result in improved clearance of Lm. Thus, despite the quantitative improvements in the NK and NKT cell responses to Lm, there was no functional improvement in the early control of Lm. CD1a+ dendritic cell percentages in the lymph nodes of FIV-infected cats were lower than in specific-pathogen-free control cats and failed to upregulate CD80 even when Treg were depleted. Taken together, Treg depletion failed to improve the innate immune response of FIV-infected cats against Lm and this may be due to dendritic cell dysfunction.

Cellular Composition of Rat Thymus with Combined Effects of Carcinogen and Stress

The aim of the research was study the effects of experimental breast cancer and stress on the thymus of laboratory animals Material and methods . Thymus 40 white nonlinear female rats of the same age were investigated using luminescent-histochemical, general histological and immunohistochemical methods . The animals were divided into 3 groups. In the 1st group were intact animals. Rats of the 2nd group were injected with N-methyl-N-nitrosourea, causing breast cancer. Animals of the 3rd group experienced a combined effect of carcinogen and water-immobilization stress. Results. It was established that the administration of N-methyl-N-nitrosourea to female rats causes an increase in the size of the medullar and cortex of the thymus lobes. In cells of the premedullary and subcapsular zones, an increase in the level of serotonin and catecholamines is observed, and in cells of the premedullary zone, in the thymocytes of the cortex and medulla - a decrease in the level of histamine. The ratio (serotonin + histamine) / catecholamines decreases and the percentage of degranulated mast cells increases. Also, the number of mature T-lymphocytes and macrophages is increasing against the background of a decrease in the number of S-100+ cells. Combined effect of factors revealed a decrease in the size of the lobes of the organ, the replacement of the parenchyma with adipose and connective tissue, an increase in the content of serotonin and catecholamines, a significant decrease in histamine levels, with a decrease in the ratio (serotonin + histamine) / catecholamines in the same cells, an increase in mature forms of T-lymphocytes and macrophages, as well as a decrease in the percentage of dendritic cells. Conclusion. The combined effect causes a more pronounced disorganization of the morphofunctional state of the thymus and leads to the 4th phase of the accidental involution of the thymus with the development of atrophy and sclerosis of the organ.