CD103 Dendritic Cells Research Articles

Intestinal lamina propria stromal cells function as the target of androgens and microbiota metabolites for the prevention of lupus.

Abstract The gut microbiota affects autoimmune diseases including lupus. We found that female and male microbiota in NZBxNZWF1 (BWF1) mice differ. Our goal is to understand the relationship between sex, microbiota and disease. Microbiota depletion in females has no impact on disease and female microbiota does not induce disease in males; male microbiota can protect female mice from disease while castrated male microbiota loses this ability (castration induces disease and alters the microbiota in males). Intestinal lamina propria stromal cells (LPSC) can affect microbiota and immunoregulation [via regulating CD103 dendritic cell (CD103DC) development and consequently, peripheral regulatory T cells (pTregs)]. CD103DC function and pTregs are both decreased in female and castrated male mice. Endogenous androgens directly induce genes, RALDH1and 2(i.e., retinoic acid production), TGFBand GM-CSF, in LPSC that are critical for CD103 development. Transferred male gut microbiota induce expression of the same genes in LPSC in female recipients that we determined was not due to androgens produced by the male microbiota, since no androgen response genes, ANGTLand CHRD, were induced in highly androgen-sensitive LPSC. The male microbiota metabolomic profile differs from either female or castrated male mice, and includes the RXR agonist metabolite(s), phytol/phytanic acid, that directly induce(s) LPSC to express RALDH1and 2, TGFBand GM-CSF. We propose that 1) endogenous androgens regulate CD103DC function and microbiota function through the LPSC in males; (2) male-modified microbiota produces metabolite(s) that may mediate protection in female recipients through the LPSC and subsequent restoration of CD103DC function and pTregs. Funded by a TIL grant from the Alliance for Lupus Research and the NIH (R01AR067188)

The atypical chemokine receptor-2 fine-tunes the immune response in herpes stromal keratitis.

Herpes stromal keratitis (HSK) is a blinding corneal disease caused by herpes simplex virus-1 (HSV-1), a common pathogen infecting most of the world's population. Inflammation in HSK is chemokine-dependent, particularly CXCL10 and less so the CC chemokines. The atypical chemokine receptor-2 (ACKR2) is a decoy receptor predominantly for pro-inflammatory CC chemokines, which regulates the inflammatory response by scavenging inflammatory chemokines thereby modulating leukocyte infiltration. Deletion of ACKR2 exacerbates and delays the resolution of the inflammatory response in most models. ACKR2 also regulates lymphangiogenesis and mammary duct development through the recruitment of tissue-remodeling macrophages. Here, we demonstrate a dose-dependent upregulation of ACKR2 during corneal HSV-1 infection. At an HSV inoculum dose of 5.4 x 105 pfu, but not at higher dose, ACKR2 deficient mice showed prolonged clinical signs of HSK, increased infiltration of leukocytes and persistent corneal neovascularization. Viral clearance and T cell activation were similar in ACKR2-/- and wild type mice, despite a transient diminished expression of CD40 and CD86 in dendritic cells. The data suggest that ACKR2 fine-tunes the inflammatory response and the level of neovascularization in the HSK.

Oxaliplatin Induces Immunogenic Cell Death in Human and Murine Laryngeal Cancer

Background Cisplatin resistance is observed in patients with laryngeal cancer. The present study was designed to explore the efficacy of oxaliplatin on laryngeal cancer and elucidate the underlying mechanisms. Methods Cell viability was determined by using MTT assays. Cell apoptosis was determined by using annexin V and propidium iodide (PI) staining. Flow cytometry and immunofluorescence were applied to determine the levels of calreticulin (CALR) and DiD (1,1-dioctadecyl-3,3,3,3-tetramethylindodicarbocyanine). Flow cytometry was applied to analyze the levels of CD83, CD86, IFN-γ-producing CD8+ T cells, and CD4+CD25+FoxP3+ Tregs. The levels of adenosine triphosphate (ATP) were determined by using a chemiluminescent ATP kit and cytokines were determined by using specific enzyme-linked immunosorbent assays (ELISAs). The levels of HMGB1 were determined by using Western blot and ELISA, respectively. The xenograft animal model was constructed to evaluate the antitumor effects of oxaliplatin. Results Oxaliplatin inhibited cell growth, promoted cell apoptosis, and induced the levels of CALR, ATP, and high mobility group box protein 1 (HMGB1) in Hep-2 cells. Oxaliplatin-treated Hep-2 cells increased the intensity of DiD and the levels of CD83 and CD86 in dendritic cells (DCs), as well as induced the supernatant IL-6 and TNF-α. Oxaliplatin-treated primary laryngeal cancer cell-pulsed DCs increased the IFN-γ-producing CD8+ T cells and suppressed CD4+CD25+FoxP3+ Tregs. In vivo data showed that oxaliplatin suppressed tumor growth and increased the populations of CD86+CD80+ and CD8+CD45+ cells in the tumor tissues. Conclusion Treatment with oxaliplatin inhibited laryngeal cancer cells by inducing immunogenic cell death.

Androgens can modulate immunoregulation directly through gut cells and indirectly through alteration of microbiota composition/function in a lupus mouse model.

Abstract Hormones and gut microbiota affect lupus. In female NZBxNZW1(BWF1) mice, androgen treatment abrogates lupus; castration/treatment with androgen receptor blocker (flutamide) induces disease in BWF1 male mice. Gut microbiota alterations have been reported in lupus. Our goal is to understand the androgen/gut microbiota relationship, and its affect on lupus. We found male castration decreases peripheral, not thymic, derived Tregs; this correlates with decreased gut CD103 dendritic cells (CD103DC) function (induce Treg conversion) and RALDH2 [required for retinoic acid (RA) production) expression. CD103DC have very low androgen receptor (AR) expression, thus unlikely to be affected by androgens. We found that lamina propria stromal cells (LPSC), a major source of RA (via RALDH1/2 expression) required for normal gut CD103DC development, express very high AR levels. Castration/flutamide treatment in male mice decreased RALDH1/2 expression in LPSC, suggesting androgens may affect CD103DC function through LPSC. Castration/flutamide treatment also altered gut microbiota composition. Interestingly, intact male microbiota transfer to castrated male mice restored RALDH2 expression and CD103DC function, suggesting male microbiota factors may also alter CD103DC function. Metabolomic analysis of castrated male feces showed reduced phytanic acid (PA) levels. Administration of PA in vitro/in vivo restored castrated CD103DC function. These data strongly suggest that androgens alter (1) immunoregulatory function through gut cells and (2) gut microbiota composition/function that in turn modulate immunoregulatory function, and reveal how androgens may influence lupus and provide the basis for effective therapy development. Funded by a TIL grant from the Alliance for Lupus Research and the NIH (R01AR067188)

Crude polysaccharides from Cistanche deserticola Y.C. Ma as an immunoregulator and an adjuvant for foot-and-mouth disease vaccine

Cistanche deserticola Y. C. Ma (CD) are ideal herbal remedies for health problems. In this study, modulator activities of CPCD on activating dendritic cells (DCs) and the adjuvant potential for foot-and-mouth disease vaccine (FMDV) was evaluated. CPCD without cytotoxicity induced DC activation via upregulating the phenotypic markers and antigen uptake. TLR-2 or TLR-4 antibodies suppressed levels of CPCD-mediated CD40 and CD86 as well as IL-6 and IL-1β in DCs. CPCD induced the phosphorylation of MAPKs related molecules and NF-κB. When co-injected intramuscularly with FMDV in mice, CPCD increased FMDV-specific antibody, lymphocyte proliferation, effector T-cells. Specifically, CPCD elicited Th1 response, as indicated by the higher expressions of CD4+ IFN-γ, CD8+ IFN-γ and CTL response. CPCD enhanced the expressions of MHC-II, CD80, CD86 and CD40 in DCs and lowered Tregs frequency. Therefore, CPCD could effectively stimulate stronger humoral and cellular responses by modulating DC activation through TLR-2/TLR-4 related MAPKs and NF-κB pathways.

Effect of dendritic cells on immune function regulated by programmed cell death-1/programmed cell death-ligand 1 in sepsis

To study the effect of programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) regulating dendritic cells (DC) on the immune status of sepsis, and analyze the effect of PD-1/PD-L1 on prognosis. Twenty-five patients with sepsis in the intensive care unit (ICU) of the Affiliated Hospital of Zunyi Medical University from October 2018 to September 2019 were collected and followed up for 28 days. According to the 28-day survival of patients, patients were divided into survival group and death group. Among them, 10 cases were in the survival group and 15 cases were in the death group. Simultaneously, 20 healthy subjects in our hospital during the same period served as the healthy control group. Peripheral blood of patients with sepsis was taken within 24 hours after diagnosis, and the healthy control group was taken at the time of enrollment. Flow cytometry was used to detect the proportion of CD4+T and CD8+T cells, the ratio of T cell subsets (CD4/CD8), the expression of PD-1 on CD4+T and CD8+T cells, and the expression of PD-L1 and CD86 in DC. Enzyme linked immunosorbent assay (ELISA) was used to detect the levels of interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α) in serum. Spearman correlation analysis was used to analyze the correlation between CD11c+PD-L1 and CD4+PD-1, CD8+PD-1, TNF-α, DC, CD11c+CD86, T cell subpopulation ratio, CD4+T cells, CD8+T cells, and IL-10. Binary Logistic regression was used to analyze the risk factors affecting the death of patients with sepsis, and receiver operator characteristic curve (ROC curve) was drawn to evaluate the predictive value of independent risk factors on the prognosis of patients. The scores of acute physiology and chronic health evaluation II (APACHE II) and sequential organ failure assessment (SOFA) in the death group were higher than that in the survival group (APACHE II score: 27.0±7.3 vs. 17.0±3.9, SOFA score: 15.1±4.1 vs. 10.7±2.7, both P < 0.05). The ratio of T cell subsets in the survival group and the death group was less than 1, the death group was lower than that in the survival group (CD4/CD8: 0.54±0.15 vs. 0.79±0.09, P < 0.05), and the ratio of T cell subsets in the healthy control group was greater than 1. Compared with healthy control group, the levels of CD4+T cells, CD8+T cells, CD11c+DC, CD11c+CD86, IL-10 and TNF-α in survival group and death group were significantly decreased, the level of CD4+PD-1,CD8+PD-1, CD11c+PD-L1 were significantly increased,and the changes in the above indicators in the death group were significant compared with the survival group [CD4+T cells: 0.14±0.07 vs. 0.22±0.08, CD8+T cells: 0.24±0.07 vs. 0.28±0.10, CD11c+DC: 0.84±0.14 vs. 0.93±0.03, CD11c+CD86: (58.83±20.77)% vs. (78.24±9.39)%, IL-10 (ng/L): 34.22±13.98 vs. 18.49±5.55, TNF-α (ng/L): 95.30±29.33 vs. 67.00±20.16, CD4+PD-1: (39.58±10.08)% vs. (27.03±6.35)%, CD8+PD-1: (38.77±11.91)% vs. (29.15±8.37)%, CD11c+PD-L1: (21.13±11.54)% vs. (12.11±8.34)%, all P < 0.05]. Spearman correlation analysis showed that CD11c+PD-L1 was positively correlated with CD4+PD-1, CD8+PD-1, and IL-10 (r values were 0.748, 0.713, 0.898, all P < 0.05), while was negatively correlated with DC, CD11c+CD86, T cell subpopulation ratio, CD4+T cells, CD8+T cells, and TNF-α (r values were -0.587, -0.906, -0.840, -0.706, -0.513, -0.820, all P < 0.05). Multivariate binary Logistic regression analysis showed that CD4+T PD-1 was an independent risk factor for the prognosis of sepsis patients [odds ratio (OR) = 1.463, 95% confidence interval (95%CI) = 1.032-2.074, P = 0.033]. ROC curve analysis showed that CD4+T PD-1 had certain predictive value for the prognosis of patients with sepsis [area under ROC curve (AUC) = 0.857, 95%CI was 0.709-1.000, P < 0.01). When the best predictive value was 34.48%, the sensitivity, specificity, and accuracy were 66.7%, 90.0%, and 85.7% respectively. Up-regulation of PD-1/PD-L1 in peripheral blood could inhibit the activation and proliferation of DC, affect the activation of T cells, and induce immunosuppressive state. PD-1/PD-L1 can reflect the immune status of patients with sepsis. The expression of PD-1 on CD4+T cells may have important significance for the evaluation of prognosis.

A mechanism of cooling hot tumors: Lactate attenuates inflammation in dendritic cells

SummaryTurning non-inflamed (cold) tumors into inflamed (hot) tumors is important for maximizing the effect of immune checkpoint inhibitors (ICIs) against malignancies. We showed that lactate, a product of the Warburg effect, inhibited the efficacy of ICIs and suppressed IL-12 p40 expression in dendritic cells (DCs) through reducing NF-κB p65, p50, and c-Rel DNA-binding activity to the IL-12 p40 promoter. Additionally, lactate promoted the expression of early growth response protein 1 (EGR1), whose expression was increased in human invasive melanoma compared with non-invasive melanoma. We also found that EGR1 interacts with serum response factor (SRF) and represses the expression of CD80 in DCs. These findings suggest that lactate and its induced EGR1 are key factors that turn hot tumors into cold tumors and may represent targets in cancer treatment with ICIs.

Differences in the Immune Response of the Nonmetastatic Axillary Lymph Nodes between Triple-Negative and Luminal A Breast Cancer Surrogate Subtypes

Breast cancer (BC) comprises four immunohistochemical surrogate subtypes of which triple-negative breast cancer (TNBC) has the highest risk of mortality. Axillary lymph nodes (ALNs) are the regions where BC cells first establish before distant metastasis, and the presence of tumor cells in the ALN causes an immune tolerance profile that contrasts with that of the nonmetastatic ALN (ALN-). However, few studies have compared the immune components of the ALNs- in BC subtypes. The present study aimed to determine whether differences between immune populations in the primary tumor and ALNs- were associated with the luminal A or TNBC subtype. We evaluated a retrospective cohort of 144 patients using paraffin-embedded biopsies. The TNBC samples tended to have a higher histologic grade and proliferation index and had higher levels of immune markers compared with luminal A in primary tumors and ALNs-. Two methods for validating the multivariate analysis found that histologic grade, intratumoral S100 dendritic cells, and CD8 T lymphocytes and CD57 natural killer cells in the ALNs- were factors associated with TNBC, whereas CD83 dendritic cells in the ALNs- were associated with the luminal A subtype. In conclusion, we found that intratumoral regions and ALNs- of TNBC contained higher concentrations of markers related to immune tolerance than luminal A. This finding partially explains the worse prognosis of patients with TNBC.

Dendritic cell-CD4+ T cell interaction: The differential role of IL-4/IL-13 in serum IgE levels in house dust mite allergic patients.

Allergic asthma is a chronic airway inflammatory disorder triggered by inhalant allergens. Interleukin (IL)-4 and IL-13 play a main role in the generation of T helper cell type 2 (Th2) immune response, induction of immunoglobulin E (IgE) synthesis and persistence of airway inflammation. The aim of the present study was to investigate the influence of Dermatophagoides pteronyssinus allergen Der p 1, the major allergen of house dust mite, on the synthesis of IL-4 and IL-13 by monocyte-derived dendritic cells (DCs) and naive CD4+ T cells cocultured with DCs, as well as their role in the production of serum IgE, in house dust mite (HDM) allergic patients. Peripheral blood mononuclear cells (PBMCs) were isolated from venous blood of patients allergic to HDM and healthy donors and incubated with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4 to generate immature DCs. The obtained cells were stimulated for 24 h with Der p 1 to induce DC maturation, washed, and afterwards cocultured for 24 h with autologous naive CD4+ T cells. Culture supernatants were harvested for IL-4, IL-13 and IFN-γ level measurements. DCs stimulation with Der p 1 induced higher synthesis of IL-4 and IL-13 in HDM allergic patients, compared to healthy donors. The allergic group showed significant correlation between IL-13 production by Der p 1-pulsed DCs, and total serum IgE and IL-4 production of the same cells and Der p-specific IgE. To conclude, IL-4 and IL-13 are critically related to the regulation of serum IgE production in patients with allergic asthma. The relevance of these two cytokines in the pathophysiology of Th2 asthma endotype makes them an appropriate target in its management.

Anti-tumor and Phenotypic Regulation Effect of Matrine on Dendritic Cells through Regulating TLRs Pathway.

To investigate the effects of matrine on antigen presentation of dendritic cells (DCs), and to explore the pharmacological mechanism of matrine on anti-tumor effect. Different concentrations (0, 1, 2, 4, 8 and 16 µ g/mL) of matrine were co-cultured with DCs, the harvested DCs were co-cultured with antigens of Lewis lung cancer (LLC) cells, and then DCs and T cells were co-cultured to produce DCs-activated killer (DAK) cells, which have significant tumor-killing activity. The expression of cytokines, mRNA and protein of toll-like receptors (TLRs) in DCs were detected by enzyme linked immunosobent assay, polymerase chain reaction and Western blot, respectively. And the killing effect of DAK were measured by MTT assay. Matrine significantly increased the mRNA expression of TLR7, TLR8, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF-6) and I κ B kinase (IKK), as well as the protein expression of TLR7 and TLR8, and up-regulated the levels of interleukin-12 (IL-12), IL-6 and tumor necrosis factor-α (TNF-α), meanwhile, it also increased the expressions of MHC-II, CD54, CD80 and CD86 in DCs. DCs-activated effector T cells had significant tumor-killing activity. When the concentration of matrine was more than 4 µg/mL, all indices had significant difference (P<0.01 or P<0.05). Matrine plays an anti-tumor role by regulating TLRs signal transduction pathway, promoting the secretion of inflammatory cytokines and enhancing immune function.

Enhanced immunogenicity of leukemia-derived exosomes via transfection with lentiviral vectors encoding costimulatory molecules

Background: Tumor cell-derived exosomes (TEXs) have been widely used to induce antitumor immune responses in animal models and clinical trials. Similarly, leukemia cell-derived exosomes (LEXs) can induce antileukemia immune responses in animal models. However, the antileukemia immunity induced by LEXs is less effective, which may be due to an inadequate costimulatory capacity.Methods: In this study, we transduced L1210 leukemia cells with a lentiviral vector encoding two B7 costimulatory molecules (CD80, CD86) and obtained LEXs that highly expressed CD80 and CD86. The antileukemia immune response derived from these LEXs was examined in vitro and in vivo in animal models.Results: We found that B7 gene-modified LEXs, including LEX-CD80, LEX-CD86, and LEX-8086, could significantly boost the expression of CD80 and CD86 in dendritic cells (DCs) and promote the secretion of functional cytokines such as TNF-α and IL-12. Moreover, these B7 gene-modified LEXs, particularly LEX-CD8086, could effectively induce CD4+ T cell proliferation, Th1 cytokine secretion, and an antigen-specific anti-leukemia cytotoxic T lymphocyte (CTL) response. Additional animal studies indicated that immunization with B7 gene-modified LEXs, in particular LEX-CD8086, could significantly retard tumor growth compared to the control LEXnull group.Conclusions: This study sheds light on the feasibility of obtaining LEXs that overexpress costimulatory molecules via genetically modified leukemia cells, thereby enhancing their anti-leukemia immunity and providing a potential therapeutic strategy that contributes to leukemia immunotherapy.

Androgens may mediate protection through an effect on immunoregulation in lupus-prone mice

Abstract Lupus is much more prevalent in females. Depleting androgens via castration increases disease and mortality in male NZBxNZWF1 (BWF1) mice, suggesting androgens are protective. We have found that treatment of male BWF1 mice with CD103-neutralizing antibody induces disease and increases mortality suggesting CD103+ cells are important for disease protection in males. Mesenteric lymph node (MLN) CD103+ dendritic cells (CD103DC) from castrated male mice exhibit decreased ability to induce conversion of CD4+Foxp3+ cells (Tregs) in vitro and decreased expression of RALDH2, an enzyme involved in retinoic acid synthesis (hallmark of CD103DC function) vs control mice. Also, castrated BWF1 male mice have significantly decreased circulating and peripheral LN Tregs vs control mice, suggesting androgens may affect Tregs via an effect on CD103DC. We have found CD103DC express androgen receptor (AR) mRNA levels that are lower than splenic macrophages (positive controls), but higher than splenic myeloid DC (negative controls) suggesting that androgens could have a direct effect on CD103DC. To determine whether signaling through the AR is required for androgen-mediated protection and CD103DC function, male BWF1 mice were treated with flutamide (AR inhibitor). Male mice treated with flutamide exhibited increased disease incidence and severity, and decreased CD103DC function including a decreased ability to induce conversion of Tregs in vitro and decreased expression of RALDH2 mRNA. Taken together, these data suggest that androgens may influence immunoregulation via a direct effect on CD103DC function and may, at least in part, mediate protection from lupus through this mechanism.

Development of allergic airway immunity depends on MARCH1-mediated ubiquitination of MHCII and CD86 in dendritic cells

Abstract Dendritic cells (DCs) play an essential role in the development of type 2 allergic immunity by presenting allergens to cognate naïve T cells inducing production of IL-4 thus priming type 2 T helper (Th2) cells. However, the molecular mechanisms underlying this function are poorly understood. We found that mice deficient in the expression of MARCH1 ubiquitin ligase in DCs were completely resistant to developing Th2 cell inflammation and eosinophilia upon airway exposure to house dust mite allergens. These mice exhibited normal expansion of allergen-specific CD4+ T cells and normal production of IFN-γ from the T cells but demonstrated a significant defect in the production of IL-4, suggesting a specific role of MARCH1 in DC priming of Th2 cells. Remarkably, mice lacking the ubiquitin acceptor amino acids of the MARCH1 substrates, MHCII and CD86, phenocopied MARCH1-deficient mice, indicating that MARCH1 promotes Th2 cell priming by mediating ubiquitination of MHCII and CD86. Ubiquitination of MHCII was important for CD11b+ DCs to transport respiratory allergens to the mediastinal lymph node whereas ubiquitination of CD86 as well as MHCII was involved in transcriptional reprograming of these DCs. In conclusion, dendritic cells depend on ubiquitination of MHCII and CD86 to condition themselves to effectively migrate to the draining lymph node and induce production of IL-4 from allergen-specific naïve CD4+ T cells.

CD40 up-regulation on dendritic cells correlates with Th17/Treg imbalance in chronic periodontitis in young population

We aimed to discover the influence of age on the development of chronic periodontitis and illustrate the molecular mechanism in this process. Blood samples were collected from 63 chronic periodontitis patients and 30 healthy controls. Th17 cell/Foxp3+ regulatory T cell (Treg) ratio and expression of costimulatory molecules in dendritic cells (DCs) were analyzed by flow cytometry. The serum levels of soluble CD40 ligand (CD40L) and IL-17 were examined by ELISA. In young chronic periodontitis patients, the Th17/Treg ratio was significantly higher than that in old patients. CD40 on DCs and serum levels of CD40L and IL-17 were all higher in young chronic periodontitis patients. Mature DCs with high CD40 expression level elevated the Th17/Treg ratio in vitro. During the pathogenesis of chronic periodontitis, young patients had higher Th17/Treg ratio than old patients and this phenomenon was in line with the differential expression levels of CD40 in DCs.

Regulatory T cells promote corneal endothelial cell survival following transplantation via interleukin-10.

The functional competence of corneal endothelial cells (CEnCs) is critical for survival of corneal allografts, but these cells are often targets of the immune response mediated by graft-attacking effector T cells. Although regulatory T cells (Tregs) have been studied for their role in regulating the host's alloimmune response towards the graft, the cytoprotective function of these cells on CEnCs has not been investigated. The aim of this study was to determine whether Tregs suppress effector T cell-mediated and inflammatory cytokine-induced CEnC death, and to elucidate the mechanism by which this cytoprotection occurs. Using 2 well-established models of corneal transplantation (low-risk and high-risk models), we show that Tregs derived from low-risk graft recipients have a superior capacity in protecting CEnCs against effector T cell-mediated and interferon-γ and tumor necrosis factor-α-induced cell death compared to Tregs derived from high-risk hosts. We further demonstrate that the cytoprotective function of Tregs derived from low-risk hosts occurs independently of direct cell-cell contact and is mediated by the immunoregulatory cytokine IL-10. Our study is the first to report that Tregs provide cytoprotection for CEnCs through secretion of IL-10, indicating potentially novel therapeutic targets for enhancing CEnC survival following corneal transplantation.

Silencing of CD86 in dendritic cells by small interfering RNA regulates cytokine production in T cells from patients with allergic rhinitis invitro.

The aim of the present study was to investigate the expression and role of the co‑stimulatory molecule T‑lymphocyte activation antigen CD86 (CD86) in dendritic cells (DCs) from the peripheral blood of patients with allergic rhinitis (AR) compared with those from healthy individuals. It was observed that mature DCs from the peripheral blood of patients with AR expressed high levels of the co‑stimulatory molecule CD86, but not CD80, compared with healthy control subjects. CD86 expression levels in DCs decreased significantly following transfection with siRNA in a lentiviral vector. Furthermore, the level of transforming growth factor‑β1 produced by T cells co‑cultured with DCs was significantly increased in the siRNA group, while interleukin (IL)‑4 and IL‑5 production was significantly decreased. The findings of the present study indicated that CD86 may play a pivotal role in the regulatory T cell/type2 helper T cell imbalance in allergic inflammation.

Inflammation Promotes Progression of Pancreatic Cancer Through WNT/β-Catenin Pathway-Dependent Manner.

Identify the molecular mechanism of inflammatory stimuli induced pancreatic cancer progression. RNA-seq, microarray assay and bioinformatics analyses were used to identify differentially expressed genes. Immunohistochemical staining was performed to evaluate CD68, CD163, β-catenin, CD103, CCL3 markers. Quantitative real-time polymerase chain reaction (qRT-PCR), luciferase reporter assay, apoptosis assay, wound healing assay and immunofluorescence were performed to study the relationship of inflammatory stimuli and WNT/β-catenin pathway. Differentially expressed genes of macrophage-conditioned medium-treated pancreatic cancer cells were related with WNT/β-catenin pathway. Inflammatory stimuli could activate WNT/β-catenin signaling pathway. In 106 pancreatic cancer patients, nuclear β-catenin expression of CD68-high group was much higher than CD68-low group (P < 0.05), as same as CD163 (P < 0.05). Inflammatory stimuli downregulated the expression of CCL3 via WNT/β-catenin pathway and inhibited the chemotaxis of CD103 dendritic cells. Six pancreatic cancer prognosis associating genes were upregulated by inflammatory stimuli via WNT/β-catenin pathway. Transforming growth factor-β promoted malignant biological behavior of pancreatic cancer cells through WNT/β-catenin pathway-dependent mechanism. Our present study provided a novel mechanism involved in the inflammation-driven cancer progression through tumor immune escape and downstream gene regulation of WNT/β-catenin pathway-dependent manner.

In situ repurposing of dendritic cells with CRISPR/Cas9-based nanomedicine to induce transplant tolerance

Organ transplantation is the only effective method to treat end-stage organ failure. However, it is continuously plagued by immune rejection, which is mostly caused by T cell-mediated reactions. Dendritic cells (DCs) are professional antigen-presenting cells, and blocking the costimulatory signaling molecule CD40 in DCs inhibits T cell activation and induces transplant tolerance. In this study, to relieve graft rejection, Cas9 mRNA (mCas9) and a guide RNA targeting the costimulatory molecule CD40 (gCD40) were prepared and encapsulated into poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PEG-b-PLGA)-based cationic lipid-assisted nanoparticles (CLAN), denoted CLANmCas9/gCD40. CLAN effectively delivered mCas9/gCD40 into DCs and disrupted CD40 in DCs at the genomic level both in vitro and in vivo. After intravenous injection into an acute mouse skin transplant model, CLANmCas9/gCD40-mediated CD40 disruption significantly inhibited T cell activation, which reduced graft damage and prolonged graft survival. This work provides a promising strategy for reprogramming DCs with nanoparticles carrying the CRISPR/Cas9 system to abate transplant rejection.

Atractylodin Suppresses Dendritic Cell Maturation and Ameliorates Collagen-Induced Arthritis in a Mouse Model.

The aim of this study was to evaluate the immunomodulatory effects of atractylodin, a polyethylene alkyne, on the maturation of bone marrow-derived dendritic cells (BM-DC) as well as its antirheumatic effect on collagen-induced arthritis (CIA) in DBA/1 mice. Our results indicate that atractylodin effectively suppressed the secretion of pro-inflammatory cytokines, expression of costimulatory molecules, and p38 MAPK, ERK, and NF-κBp65 signaling pathways in LPS-incubated dendritic cells (DCs). Additionally, the proliferation and cytokine secretion (IFN-γ and IL-17A) of CD8+ and CD4+ T cells were reduced. In a murine CIA model, intraperitoneal injection of atractylodin significantly alleviated the severity of the disease progression, as indicated by reduced paw swelling, clinical arthritis scores, and pathological changes of joint tissues. In addition, the overall proliferation of T cells stimulated by type II collagen and the abundance of Th1 and Th17 in the spleens were also significantly decreased with atractylodin treatments. Furthermore, atractylodin significantly downregulated the expression levels of CD40, CD80, and CD86 of DCs in the spleens. In conclusion, this study shows for the first time that atractylodin has potential to manipulate the maturation of BM-DCs and should be further explored as a therapeutic agent in the treatment of rheumatoid arthritis (RA).

Phenotypic and functional characterisation of expanded antigen-specific regulatory T cells (Ag-sp Treg), towards clinical translation

Abstract Treg infusion for graft-versus-host-disease treatment has been increasingly investigated. Yet, Treg of unknown specificity may suppress graft-versus-leukemia. To ascertain the factors affecting Ag-sp Treg potency and specificity of suppression, we assessed Ag-sp Treg phenotype and function within different expansion conditions and suppression assay (SA) milieus. Ex vivo Treg were co-cultured with monocyte-derived dendritic cells (DC) presenting allogeneic Ag directly (allo-DC) or indirectly (self-DC loaded with allo-lysate). Suppression of effector proliferation and cytokine secretion was assessed in SA with the same DC as in expansion (original) or 3rd party DC (3P) from various donors. Ag-sp Treg significantly suppressed Tcon and CD8+ T cell responses to original DC. Directly expanded cells suppressed responses to Ag presented direct and indirectly; however, indirectly expanded cells were less suppressive of responses to allo-DC. More potent Treg were less specific in their suppression of Tcon. Still, responses to 3P donors with MHC matches to original DC donor were significantly more suppressed than responses to unmatched 3P donors. Potency of suppression was also negatively correlated to expression of CD86 and CD83 in DC. Finally, FlowSOM analysis showed minimal overlap between Ag-sp Treg and activated Tcon phenotypes, suggesting Ag-sp Treg were pure. K-means clustering of Ag-sp Treg expression of CD137, CD154, CTLA-4, PD-1, CTLA-4 and HLA-DR identified clusters that may be correlated to Treg function. We propose the specificity of Ag-sp Treg function in the inflammatory milieu is a result of Treg phenotype, type of responders, DC co-stimulation and degree of MHC match between expansion DC and DC present in the milieu.