Production of dendritic cell vaccines using different methods with equivalent results: Implications for emerging centers

Introduction Dendritic cell (DC) vaccines have demonstrated good efficacy in preventing relapse and in increasing survival of patients affected by a variety of both solid and hematological tumors. Most protocols used to generate these cells involve the automated separation of peripheral blood monocytes from patients. This approach requires specialized equipment, which elevates the cost of this type of therapy, potentially limiting the widespread access to patients. Method: In this study, we compare the yield and quality of dendritic cells generated from monocytes and isolated by an automated method or by manual methods using gradient centrifugation. Results The results demonstrate the equivalence of the 3 methods in relation to the yield and final quality of the product, however with considerable differences between the costs of these procedures. In addition, this study also demonstrates the feasibility of the antigenic pulse with autologous tumor cell lysates, constituting a source of antigens, not only easily obtained and manipulated, but also specific to the patient's tumor. Conclusion These findings may have important implications for emerging centers interested in using this medical approach and potentially increase the access of a greater number of patients to this therapeutic option.

Correlation analysis between peripheral blood dendritic cell subsets and PD-1 in patients with peritoneal adenocarcinoma

Abstract The aim of this study was to explore the association between differential percentages of dendritic cell (DC) subsets in peripheral blood and malignancy (grade and lymph node metastasis) of peritoneal adenocarcinoma patients and the frequencies of dendritic cell subsets in the normal controls. The peripheral blood of 30 patients with peritoneal adenocarcinoma and 12 healthy controls were collected for multicolor flow cytometry analysis. Peritoneal adenocarcinoma patients were grouped according to the malignant degree (grade and lymph node metastasis). Percentages of myeloid DCs (mDCs) and its subsets MDC1 and MDC2 in DCs were lower in peripheral blood of patients with peritoneal adenocarcinoma than in normal controls. The percentages of plasmacytoid dendritic cells (pDCs) and CD16+mDCs in DCs were higher than in normal controls. Compared with poor differentiation grade, patients with well/moderate differentiation grade had an increased percentage of CD16+mDCs. Contrary to CD16+mDCs, the percentage of MDC1 was lower in the well/moderate differentiation grade group. In patients with no lymph node metastasis, pDCs and CD16+mDCs levels were higher compared with patients with lymph node metastasis. mDCs and MDC1 levels had opposite results. pDCs were positively correlated with CD16+mDCs in peripheral blood of peritoneal patients, as was mDCs and MDC1. CD16+mDCs were negatively correlated with MDC1. The percentages of pDCs and CD16+mDCs in DCs were positively correlated with CD3+CD8+T cells, and pDCs also positively correlated with CD8+PD-1+T cells. Our results revealed that DCs subsets correlated with peritoneal adenocarcinoma malignancy. Dendritic cells play an independent role in the immune function of peritoneal adenocarcinoma.

Effects of HMGB1 on phenotypes, phagocytosis and ERK/JNK/P38 MAPK signaling pathway in dendritic cells / 中国药理学通报

Aim To explore the impacts of high mobility group box 1 (HMGB1) on the phenotypes, endocy-tosis and extracellular signal-regulated kinase (ERK)/ Jun N-terminal protein kinase (JNK)/P38 mitogen-ac-tivated protein kinase (MAPK) signaling pathway in indoxyl sulfate (IS) -induced dendritic cells (DCs). Methods After treatment with 30, 300 and 600 (xmol · L

Estudo da ativação e modulação da resposta imune contra a esporotricose experimental, a partir de vesículas extracelulares purificadas de células dendríticas / Study of the activation and modulation of the immune response against experimental sporotrichosis, using extracellular vesicles purified from dendritic cells

A esporotricose é uma zoonose micótica emergente e subcutânea, que afeta a pele, o sistema linfático e outros órgãos de humanos e animais. Assim como outras doenças infecciosas fúngicas, se torna ainda mais grave quando acomete pacientes imunossuprimidos. Essa infecção possui distribuição global e é endêmica em algumas regiões do Brasil e de outros países tropicais e subtropicais, sendo um problema de saúde pública importante em nosso país. A doença é causada por um complexo de pelo menos quatro espécies patogênicas, incluindo o Sporothrix brasiliensis (S. brasiliensis). A resposta imunológica contra estas espécies ainda não é completamente elucidada, mas estruturas como as vesículas extracelulares (VEs) poderiam transportar componentes importantes que podem contribuir na modulação e no controle desta importante infecção. Assim, o objetivo deste trabalho, é analisar a participação das VEs de células dendríticas (DCs) naive e VEs de DCs previamente primadas com leveduras de S. brasiliensis e primadas com VEs do fungo, na resposta imune contra a esporotricose experimental em modelos murinos. Para isso, as DCs obtidas da medula óssea de camundongos, foram cultivadas com leveduras de S. brasiliensis ou com VEs do fungo e posteriormente, VEs totais das DCs foram purificadas a partir de ultracentrifugação e analisadas quanto a sua participação na modulação da resposta imunológica. Essas VEs foram utilizadas em protocolo profilático em modelos murinos, previamente a infecção subcutânea experimental. Foi observado o diâmetro médio das lesões no decorrer de 35 dias de infecção e a carga fúngica da lesão na pele. Os resultados obtidos mostram que as VEs de DCs naive, e VEs de DCs previamente cultivadas com leveduras do fungo ou com VEs fúngicas, são capazes de modular a carga fúngica. Os grupos que receberam VEs de DCs de forma profilática, de modo geral apresentaram diminuição significativa da carga fúngica em relação ao grupo controle. Na análise comparativa apenas dos grupos que receberam a profilaxia, observa-se que o uso de VEs de DCs naive, resultam em uma carga fúngica maior que o uso de VEs de DCs previamente ativadas, e quando as DCs são ativadas com levedura, essa carga fúngica é a menor. Quando analisamos o perfil de citocinas na pele de camundongos tratados com as VEs previamente a infecção, observamos aumento de IFN-γ, TNF-α, IL-17 e IL-10 principalmente nos animais previamente tratados com VEs de DCs que foram ativadas com leveduras. Em relação às citocinas produzidas, podemos sugerir até o momento, uma resposta imunológica mista, mas que de alguma maneira, ainda não esclarecida, devem contribuir para melhor controle do processo infeccioso in vivo. Em relação a linfoproliferação, observa-se principalmente um aumento de linfócitos T CD4+ quando acrescentamos VEs de DCs que não foram previamente ativadas, mostrando uma ação de uma resposta mais inespecífica. Vale ressaltar que todos os protocolos profiláticos foram capazes de modular e minimizar o crescimento fúngico, quando comparados ao controle, ou seja, as VEs contribuíram com o controle da infecção e agiram a favor do hospedeiro, demonstrando um caráter protetivo

Sporotrichosis is an emerging subcutaneous mycotic zoonosis that affects the skin, lymphatic system, and other organs of humans and animals, and like other infectious fungal diseases, it becomes even more serious when it affects immunosuppressed patients. This infection has a global distribution and is endemic in some regions of Brazil and other tropicals and subtropicals countries, being an important public health problem in our country. The disease is caused by a complex of at least four pathogenic species, including Sporothrix brasiliensis (S. brasiliensis). The immunological response against these species has not yet been completely elucidated, but structures such as extracellular vesicles (EVs) could carry important components that can contribute to the modulation and control of this important infection. Thus, the objective of this work is to analyze the participation of EVs from naïve dendritic cells (DCs) and EVs from DCs previously primed with S. brasiliensis yeast and primed with EVs from the fungus, in the immune response against experimental sporotrichosis in murine models. For this, DCs obtained from the bone marrow of mice were cultivated with S. brasiliensis yeast or EVs from the fungus, and subsequently, total EVs from the DCs were purified through ultracentrifugation and analyzed for their participation in modulating the immune response. These EVs were used in a prophylactic protocol in murine models, before experimental subcutaneous infection. The average diameter of the lesions over 35 days of infection and the fungal load of the lesion on the skin were observed. The results obtained show that EVs from naïve DCs, and EVs from DCs previously cultured with yeast or fungal EVs, are capable of modulating the fungal load. The groups that received EVs from DCs prophylactically generally showed a significant decrease in fungal load compared to the control group. In the comparative analysis of only the groups that received prophylaxis, it was observed that the use of EVs from naïve DCs results in a higher fungal load than the use of EVs from previously activated DCs, and when the DCs are activated with yeast, this load fungal is smaller. When we analyzed the cytokine profile in the skin of mice treated with EVs before infection, we observed an increase in IFN-γ, TNF-α, IL-17, and IL-10, mainly in animals previously treated with EVs from DCs that were activated with yeast. About the cytokines produced, we can so far suggest a mixed immunological response, but in some way, not yet clear, they should contribute to better control of the infectious process in vivo. About lymphoproliferation, an increase in CD4+ T lymphocytes is mainly observed when we add EVs from DCs that were not previously activated, showing a more nonspecific response. It is worth highlighting that all prophylactic protocols were able to modulate and minimize fungal growth, when compared to the control, that is, EVs contributed to the control of the infection and acted in favor of the host, demonstrating a protective character

Diacerein mitigates renal ischemia/reperfusion injury via inhibition of renal inflammation, dendritic cells maturation and apoptosis: the role of TLR4/NF-kB/NLRP3/IL-1beta signaling pathway / La diacereína mitiga la lesión por isquemia/reperfusión renal a través de la inhibición de la inflamación renal, la maduración de las células dendríticas y la apoptosis: el papel de la vía de señalización TLR4/NF-kB/NLRP3/IL-1beta

SUMMARY: One of the reasons for acute kidney damage is renal ischemia. Nevertheless, there are limited protective and therapeutic approaches for this problem. Diacerein is an anti-inflammatory drug characterized by numerous biological activities. We aimed to determine the ameliorative impact of diacerein on renal ischemia/reperfusion injury (I/R) condition, exploring the underlying mechanisms. Twenty-four male rats were allotted into four groups (n= 6): sham group; Diacerein (DIA) group; I/R group, in which a non-crushing clamp occluded the left renal pedicle for 45 min, and the right kidney was nephrectomized for 5 min before the reperfusion process; I/R + diacerein group, injected intraperitoneally with 50 mg diacerein/kg i.m 30 minutes prior to I/R operation. Ischemia/ reperfusion was found to affect renal function and induce histopathological alterations. The flow cytometry analysis demonstrated an elevated expression of innate and mature dendritic cells in I/R renal tissues. Moreover, upregulation in the expression of the inflammatory genes (TLR4, Myd88, and NLRP3), and overexpression of the pro-inflammatory cytokines (IL-1β), apoptotic (caspase-3) and pyroptotic (caspase-1) markers were observed in I/R-experienced animals. The aforementioned deteriorations were mitigated by pre-I/R diacerein treatment. Diacerein alleviated I/R-induced inflammation and apoptosis. Thus, it could be a promising protective agent against I/R.

La isquemia renal es una de los motivos del daño renal agudo. Sin embargo, los enfoques protectores y terapéuticos para este problema son limitados. La diacereína es un fármaco antiinflamatorio caracterizado por numerosas actividades biológicas. Nuestro objetivo fue determinar el impacto de mejora de la diacereína en la condición de lesión por isquemia/ reperfusión renal (I/R), explorando los mecanismos subyacentes. Veinticuatro ratas macho se distribuyeron en cuatro grupos (n= 6): grupo simulado; grupo de diacereína (DIA); grupo I/R, en el que una pinza no aplastante ocluyó el pedículo renal izquierdo durante 45 min, y el riñón derecho fue nefrectomizado durante 5 min antes del proceso de reperfusión; Grupo I/R + diacereína, inyectado por vía intraperitoneal con 50 mg de diacereína/kg i.m. 30 min antes de la operación I/R. Se encontró que la isquemia/ reperfusión afecta la función renal e induce alteraciones histopatológicas. El análisis de citometría de flujo demostró una expresión elevada de células dendríticas innatas y maduras en tejidos renales I/R. Además, se observó una regulación positiva en la expresión de los genes inflamatorios (TLR4, Myd88 y NLRP3) y una sobreexpresión de las citoquinas proinflamatorias (IL-1β), marcadores apoptóticos (caspasa-3) y piroptóticos (caspasa-1) en animales con experiencia en I/R. Los deterioros antes mencionados fueron mitigados por el tratamiento previo a la diacereína I/R. La diacereína alivió la inflamación y la apoptosis inducidas por I/R. Por lo tanto, podría ser un agente protector prometedor contra I/R.

Effects of 0.05% cyclosporine eye drops(Ⅱ)on corneal nerves of patients with moderate to severe dry eye / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the efficacy of domestic cyclosporine A(CsA)in dry eye and its effect on sub-basal nerves(SBN)by observing quantitative and morphological changes in corneal SBN of patients with moderate to severe dry eye before and after the treatment with 0.05% CsA eye drops(Ⅱ).METHODS: In this prospective study, a total of 20 patients(20 eyes)with moderate to severe dry eye who admitted to the ophthalmology department of the Affiliated Eye Hospital of Nanchang University from December 2020 to January 2022 were selected. They were treated with domestic CsA and followed up for 3mo. Clinical evaluation was carried out at baseline and at 3mo after treatment. The changes in clinical symptoms, signs and morphology and quantity of SBN were observed.RESULTS: The ocular surface disease index(OSDI)score, the tear break-up time(TBUT), Schirmer Ⅰ, corneal fluorescein staining(CFS)score were significantly improved at 3mo after treatment. Confocal microscopy data analysis showed that SBN density increased from 13.49±5.43 mm/mm2 to 14.93±5.34 mm/mm2(P<0.001), nerve curvature scores decreased from 2.86±0.92 to 2.31±0.75(P<0.001), number of beaded structure decreased from 1.45±0.67/100μm to 1.07±0.45/100μm(P<0.001), and the number of dendritic cell(DC)decreased from 5.83±3.28 per frame to 3.67±2.24 per frame at 3mo after treatment(P<0.001). The number of DC was positively correlated with the number of branch nerves, the grade of nerve curvature and the number of nerve bead.(rs=0.27, P=0.045; rs=0.407, P<0.01; rs=0.486, P<0.01).CONCLUSIONS: Nerve injury was positively correlated with corneal inflammation caused by dry eye, and 0.05%CsA eye drops(II)could effectively inhibit inflammation and improve the morphology and quantity of corneal SBN. Observation of corneal SBN via in vivo confocal microscopy can be used as an effective method to evaluate the therapeutic effect of dry eye patients.

Bone-derived MSCs encapsulated in alginate hydrogel prevent collagen-induced arthritis in mice through the activation of adenosine A2A/2B receptors in tolerogenic dendritic cells

Tolerogenic dendritic cells (tolDCs) facilitate the suppression of autoimmune responses by differentiating regulatory T cells (Treg). The dysfunction of immunotolerance results in the development of autoimmune diseases, such as rheumatoid arthritis (RA). As multipotent progenitor cells, mesenchymal stem cells (MSCs), can regulate dendritic cells (DCs) to restore their immunosuppressive function and prevent disease development. However, the underlying mechanisms of MSCs in regulating DCs still need to be better defined. Simultaneously, the delivery system for MSCs also influences their function. Herein, MSCs are encapsulated in alginate hydrogel to improve cell survival and retention in situ, maximizing efficacy in vivo. The three-dimensional co-culture of encapsulated MSCs with DCs demonstrates that MSCs can inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines. In the collagen-induced arthritis (CIA) mice model, alginate hydrogel encapsulated MSCs induce a significantly higher expression of CD39+CD73+ on MSCs. These enzymes hydrolyze ATP to adenosine and activate A2A/2B receptors on immature DCs, further promoting the phenotypic transformation of DCs to tolDCs and regulating naïve T cells to Tregs. Therefore, encapsulated MSCs obviously alleviate the inflammatory response and prevent CIA progression. This finding clarifies the mechanism of MSCs-DCs crosstalk in eliciting the immunosuppression effect and provides insights into hydrogel-promoted stem cell therapy for autoimmune diseases.

Research progress in plasmacytoid dendritic cells in systemic sclerosis / 中华微生物学和免疫学杂志

Plasmacytoid dendritic cells (pDCs) are a unique subset of dendritic cells that can rapidly produce large amounts of type Ⅰ interferon after activation. They are critical in antiviral immunity and involved in the initiation and development of many autoimmune diseases. Systemic sclerosis (SSc) is an autoimmune disease characterized by immune dysregulation, vasculopathy and progressive fibrosis of the skin and internal organs. Recent studies have found that pDCs are involved in the pathogenesis of SSc. Inhibiting the function of pDCs can effectively prevent inflammation and fibrosis in SSc, highlighting the role of pDCs in the pathogenesis of SSc. Therefore, an in-depth understanding of pDCs and their role in the pathogenesis of SSc is important for the development of pDCs and their mediators as therapeutic targets for SSc.

Role of tripartite motif-containing 23 in the differentiation and maturation of dendritic cells / 中华微生物学和免疫学杂志

Objective:To investigate the effect of tripartite motif-containing 23 (Trim23) on the differentiation and maturation of dendritic cells and the possible mechanism.Methods:Mouse bone marrow-derived dendritic cells (BMDCs) were prepared from bone marrow cells of C57BL/6 mice with the presence of Flt3L. Real-time quantitative PCR and Western blot were used to detect the expression of Trim23 in BMDCs after LPS stimulation. An overexpression vector for full-length Trim23 (Trim23 OE) was constructed and transfected into BMDCs, and the pcDNA3.1 empty vector was used as control. Flow cytometry was used to detect the expression of CD80, CD86, CD40 and MHCⅡ on the surface of vector-transfected BMDCs after LPS stimulation and ELISA was used to detect the secretion of IL-12p40, TNF-α, IL-6 and IL-10 by these cells. CD8 + and CD4 + T cells were isolated from spleen and lymph nodes of OT-Ⅰ and OT-Ⅱ mice by magnetic beads and co-cultured with LPS-treated BMDCs in the presence of ovalbumin (OVA). Flow cytometry was used to detect the proliferation and differentiation of CD8 + and CD4 + T cells. Western blot was performed to analyze the phosphorylation of p38, ERK1/2 and AKT in BMDCs. Two overexpression vectors for Trim23 mutants lacking RING or ARF domain (Trim23 ΔRING and Trim23 ΔARF) were constructed and transfected into BMDCs. Then flow cytometry and ELISA were used to detect the expression of surface molecules and cytokines. Results:The expression of Trim23 in BMDCs was significantly down-regulated after LPS stimulation. The expression of MHCⅡ, CD86 and CD80 and the secretion of TNF-α and IL-6 decreased significantly in BMDCs overexpressing Trim23. Furthermore, overexpression of Trim23 inhibited the ability of BMDCs to induce the proliferation and differentiation of CD4 + T cells and the proliferation of CD8 + T cells. Western blot showed that the phosphorylation of p38 and ERK1/2 decreased significantly in Trim23-overexpressing BMDCs. Compared with wildtype Trim23, overexpression of Trim23 ΔRING had no significant influence on the expression of surface molecules (MHCⅡ and CD86) and the secretion of cytokines (TNF-α and IL-6) in BMDCs stimulated by LPS. Conclusions:Trim23 overexpression inhibited the maturation and immune activation of BMDCs via MAPK signal pathway and its RING domain. This study provided reference for targeting Trim23 to improve the immune response of dendritic cell-based tumor vaccines.

Tolerogenic dendritic cells involve in reconstructing T cell balance in neuroimmune conditions / 中华神经科杂志

Dendritic cells are the most powerful antigen-presenting cells in the human body, which are involved in the occurrence and development of multiple sclerosis, neuromyelitis optica, myasthenia gravis and other neuroimmune conditions. Recently, tolerogenic dendritic cells (tolDCs) are gradually becoming the research focus and therapeutic target of neuroimmune conditions. They can reconstruct the balance of T cells by inducing effector T cell anergy/deletion, and producing antigen-specific regulatory T cells, ultimately achieving the goal of maintaining immune tolerance. In this review, the mechanisms that tolDCs reconstruct T cell balance in neuroimmune conditions are analyzed and the research progress related to tolDC therapy is summarized.

Effects of co-culture of dendritic cells loaded with MAGE-A3 antigen and cytokine-induced killer cells on tumor stem cells and malignant progression of endometrial cancer / 中国临床药理学与治疗学

AIM: To explore the effects of dendritic cells (DC) and cytokine-induced killer cells (CIK) carrying melanoma-associated antigen gene A3 (MAGE-A3) on endometrial cancer tumor stem cells and malignant progression. METHODS: Human peripheral blood was collected to separate mono-nuclear cells, and DC and CIK cells were induced by cytokines, respectively. DCs were incubated with MAGE-A3 and then co-cultured with CIK, and the phenotypes of DC-CIK and MAGE-A3-DC-CIK were detected by flow cytometry; The CD133

Effects of lentinan on dendritic cell metabolism / 中国药理学通报

Aim To study the effects of lentinan(LNT)on the metabolism of dendritic cells(DCs)by metabonomics, and uncover the potential mechanism of its regulation of DC function. Methods DC2.4 cells were co-incubated with LNT for 24 h, and the activity of the cells was detected by thiazolyl blue tetrazolium bromide(MTT)assay. The contents of interleukin-6(IL-6), tumor necrosis factorα(TNF-α)and interleukin-12(IL-12)in supernatant were detected by enzyme-linked immunosorbent assay(ELISA). The metabolic general changes of DC2.4 cells were detected by Ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-QTOF/MS), and the differential metabolites were analyzed by multi-distance covariates and bioinformatics, partial least squares-discriminant analysis(PLS-DA). Finally, metabolic pathway analysis was performed by MetaboAnalyst 5.0. Results LNT did not significantly inhibit the activity of DC2.4 cells at the dose of 25100 mg·L-1. LNT(100 mg·L-1)could significantly stimulate the secretion of IL-6, TNF-α and IL-12 in DC2.4 cells. 20 differential metabolites were identified in DC2.4 cells after being stimulated by LNT(100 mg·L-1), which involved 25 metabolic pathways including urea cycle, arginine and proline metabolism. Conclusion The regulation of LNT on DC function involves a variety of amino acid metabolism.

JAK inhibition ameliorated experimental autoimmune encephalomyelitis by blocking GM-CSF-driven inflammatory signature of monocytes

Monocytes are key effectors in autoimmunity-related diseases in the central nervous system (CNS) due to the critical roles of these cells in the production of proinflammatory cytokines, differentiation of T-helper (Th) cells, and antigen presentation. The JAK-STAT signaling is crucial for initiating monocytes induced immune responses by relaying cytokines signaling. However, the role of this pathway in modulating the communication between monocytes and Th cells in the pathogenesis of multiple sclerosis (MS) is unclear. Here, we show that the JAK1/2/3 and STAT1/3/5/6 subtypes involved in the demyelination mediated by the differentiation of pathological Th1 and Th17 and the CNS-infiltrating inflammatory monocytes in experimental autoimmune encephalomyelitis (EAE), a model for MS. JAK inhibition prevented the CNS-infiltrating CCR2-dependent Ly6Chi monocytes and monocyte-derived dendritic cells in EAE mice. In parallel, the proportion of GM-CSF+CD4+ T cells and GM-CSF secretion were decreased in pathological Th17 cells by JAK inhibition, which in turns converted CNS-invading monocytes into antigen-presenting cells to mediate tissue damage. Together, our data highlight the therapeutic potential of JAK inhibition in treating EAE by blocking the GM-CSF-driven inflammatory signature of monocytes.

Immune enhancement of 30% ethanol elution fraction of Artemisia absinthium ethanol extract with macroporous resin / 国际生物医学工程杂志

Objective:To investigate the effects of 30% ethanol elution fraction of Artemisia absinthium extract with macroporous resin (AAEM-30%) on the dendritic cell (DC) and immunity of mice. Methods:AAEM-30% was obtained from the alcoholic extracts of A. absinthium by AB-8 macroporous resin, and its polysaccharide, flavonoid, and terpenoid contents were determined. The expressions of AAEM-30% on DC surface molecular cluster of differentiation (CD) 40, CD80 and CD86 were detected in vitro by flow cytometry, and the expressions of DC cytokines IL-6 and tumor necrosis factor-α (TNF-α) were detected by enzyme linked immunosorbent assay (ELISA). The effect of AAEM-30% on the immune function of ICR mice was measured in vivo with different doses (50 and 100 mg/kg) and different administration methods (subcutaneous injection, intraperitoneal injection, and gavage). Results:The contents of polysaccharides, flavonoids, and terpenoids in AAEM-30% were 24.30%, 22.50% and 28.19%, respectively. AAEM-30% significantly enhanced the expression of CD40, and CD86 and the secretion of IL-6 and TNF-α (all P<0.001). Compared with the control group, no statistically significant differences were found in the body mass of mice compared with the three administration methods (all P>0.05). The thymus index in the 50 and 100 mg/kg AAEM-30% intraperitoneal injection groups and the spleen index in the 50 mg/kg AAEM-30% gavage group were increased (all P<0.05). CD19 + cells increased in the 100 mg/kg AAEM-30% intraperitoneal injection group ( P<0.01) and in the 50 mg/kg AAEM-30% gavage group ( P<0.05). The CD11b + and CD11c + counts increased in the 100 mg/kg AAEM-30% gavage group ( P<0.05). The number of CD4 + and CD8 + T lymphocytes was increased by both gavage and intraperitoneal administration (all P<0.05). Conclusions:AAEM-30% can promote the maturation of DC and enhanced the immunity of mice without obvious side effects.

Progress in Biomechanics and Mechanobiology of Dendritic Cells / 医用生物力学

Dendritic cells (DCs) are now known as the most powerful antigen-presenting cells in vivo, with efficient antigen uptaking, and processing capabilities. They can present antigens to naïve T cells in secondary lymphoid tissues, thereby induce immune response or tolerance, and play a key role in initiating and amplifying innate and adaptive immunity. DCs experience complex chemical and mechanical microenvironment changes and show different mechanophenotypes and immunophenotypes in the process of exerting their physiological functions. Deeply understanding the chemical and mechanical factors that regulate the mechanophenotypes and immunophenotypes of DCs is a prerequisite for using DCs to treat immune related diseases. In this review, the progress in the biomechanics and mechanobiology research of DCs was mainly introduced, and their potential applications and future development directions in the treatment of immune related diseases were explored.

An mRNA vaccine elicits STING-dependent antitumor immune responses

Lipid-formulated RNA vaccines have been widely used for disease prevention and treatment, yet their mechanism of action and individual components contributing to such actions remain to be delineated. Here, we show that a therapeutic cancer vaccine composed of a protamine/mRNA core and a lipid shell is highly potent in promoting cytotoxic CD8+ T cell responses and mediating anti-tumor immunity. Mechanistically, both the mRNA core and lipid shell are needed to fully stimulate the expression of type I interferons and inflammatory cytokines in dendritic cells. Stimulation of interferon-β expression is exclusively dependent on STING, and antitumor activity from the mRNA vaccine is significantly compromised in mice with a defective Sting gene. Thus, the mRNA vaccine elicits STING-dependent antitumor immunity.

Effect of propolis on Th2 and Th17 cells: interplay with EtxB- and LPS-treated dendritic cells

Dendritic cells (DCs) are antigen-presenting cells that drive the differentiation of T CD4+ cells into different profiles according to the nature of the antigen or immunomodulator. Propolis is a resinous product made by bees that has numerous pharmacological properties, including an immunomodulatory action. To assess whether propolis can modulate the activation of CD4+ T cells by stimulating DCs with heat-labile enterotoxin B subunit (EtxB) or lipopolysaccharide (LPS), we aimed to elucidate the mechanisms affected by propolis in the differential activation of T lymphocytes. Cell viability, lymphocyte proliferation, gene expression (GATA-3 and RORc), and cytokine production (interleukin (IL)-4 and IL-17A) were analyzed. Propolis, EtxB, and LPS induced a higher lymphoproliferation compared with the control. Propolis induced GATA-3 expression and, in combination with EtxB, maintained the baseline levels. Propolis alone or in combination with LPS inhibited RORc expression. EtxB alone and in combination with propolis increased IL-4 production. Propolis in combination with LPS prevented LPS-induced IL-17A production. These results opened perspectives for the study of biological events that may be favored by propolis by promoting Th2 activation or helping in the treatment of inflammatory conditions mediated by Th17 cells.

Novas perspectivas em imunoterapia: a importância das células dendríticas na imunoterapia alérgeno-específica / New perspectives in immunotherapy: the importance of dendritic cells in allergen-specific immunotherapy

A imunoterapia alérgeno-específica é o único tratamento capaz de alterar o curso natural da doença alérgica. Ensaios clínicos mostram que a imunoterapia é segura e eficaz para muitos pacientes. No entanto, ainda enfrenta problemas relacionados à eficácia, segurança, longa duração do tratamento e baixa adesão dos pacientes. Neste contexto, tem havido intensa pesquisa no desenvolvimento de adjuvantes com objetivo de aumentar a segurança, otimizar os esquemas de tratamento e melhorar a adesão dos pacientes. Alérgenos foram modificados (glicoconjugados) com carboidratos derivados de Saccharomyces cerevisae para aumentar sua captação e apresentação através dos receptores de carboidratos presentes nas células dendríticas, beneficiando-se da capacidade de atuarem na indução de tolerância para iniciar respostas imunes. À luz de novas evidências, essas células constituem alvo terapêutico chave para se obter uma resposta adequada à imunoterapia alérgeno-específica, com potencial de contribuição na inovação do campo da Imunoterapia.

Allergen-specific immunotherapy is the only treatment capable of altering the natural course of allergic disease. Clinical trials have shown that immunotherapy is safe and effective for many patients. However, it still faces problems related to efficacy, safety, long treatment duration and poor patient compliance. In this context, there has been intense research into the development of adjuvant treatments that increase safety, optimize treatment regimens, and improve patient compliance. Allergens were modified (glycoconjugated) with carbohydrates derived from Saccharomyces cerevisae to increase their uptake and presentation through carbohydrate receptors in dendritic cells, benefiting from their ability to induce tolerance and initiate immune response. In light of the new evidence, these cells are a key therapeutic target for adequate response to allergenspecific immunotherapy and can drive innovation in the field of immunotherapy.

Mecanismo de células dendríticas derivadas de sangre periférica humana en la regulación de la autofagia en células de carcinoma / Mechanism of human peripheral blood-derived dendritic cells in the regulation of autophagy in carcinoma cells

Resumen Introducción: Las células dendríticas (CD) están involucradas en el reconocimiento, respuesta y modulación inmunológicos relacionados con la aparición del cáncer. Objetivo: Explorar el mecanismo de las CD en la inhibición de la autofagia de las células del hepatoma. Métodos: Células mononucleares de sangre periférica humana se aislaron mediante centrifugación en gradiente de densidad de Ficoll y se indujeron en CD, las cuales fueron cocultivadas con células HepG2 por ensayo de migración Transwell. La actividad de las células HepG2 se determinó mediante ensayo CCK8. La expresión del índice de autofagia LC3 se midió con análisis de transferencia Western y la expresión y secreción de citocinas mediante qRT-PCR y ELISA. Resultados: En el sistema de cocultivo, las CD redujeron la viabilidad de HepG2; la expresión de IL-2, IL-12, IL-10 e IFN-γ en CD también se inhibió significativamente, si bien IL-2 e IFN-γ aún se expresaron 0.6 y 0.53 más que en el grupo de control. Conclusión: Las CD pueden regular la autofagia de las células del carcinoma hepatocelular. El mecanismo puede estar relacionado con la síntesis y liberación de citocinas como IL-2, IL-12 e IFN-γ por parte de las CD.

Abstract Introduction: Dendritic cells (DC) are involved in immune recognition, response and immunomodulation mechanisms related to the onset of cancer. Objective: To explore DCs mechanism in the inhibition of autophagy in hepatoma cells. Methods: Human peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation and induced into DCs, which were co-cultured with HepG2 cells by Transwell migration assay. HepG2 cell activity was determined using the CCK8 assay. LC3 autophagy index expression was measured with Western blot analysis, and the expression and secretion of cytokines, with qRT-PCR and ELISA. Results: In the co-culture system, DCs were able to reduce HepG2 cells viability; IL-2, IL-12, IL-10 and IFN-γ expression in DCs was also significantly inhibited, although IL-2 and IFN-γ were still expressed 0.6 and 0.53 more than in the control group. Conclusion: DCs can regulate autophagy in hepatocellular carcinoma cells. The mechanism may be related to the synthesis and release of cytokines such as IL-2, IL-12 and IFN-γ by DCs.

Inhibitory effect of RMT1-10-induced tolerogenic dendritic cells in vitro on high-risk corneal allograft rejection in mice and its mechanism / 中华实验眼科杂志

Objective:To investigate the inhibitory effect of RMT1-10-induced tolerogenic dendritic cells (Tol-DCs) in vitro on high-risk corneal allograft rejection in mice and its mechanism. Methods:One hundred SPF male BALB/c mice and fifty SPF male C57BL/6 mice were selected.Bone marrow-derived immature dendritic cells (imDCs) obtained from C57BL/6 mice were divided into imDCs group, mature dentritic cells (mDCs) group, RMT1-10 group, and IgG isotype control group.The imDCs in the four groups were cultured with no intervention, lipopolysaccharide, RMT1-10 and lipopolysaccharide, or IgG isotype antibody and lipopolysaccharide for 7 days according to grouping.The expression levels of different phenotypes of DCs including CD11c, CD80, CD86, major histocompatibility complex (MHC)-Ⅱ, T cell immunoglobulin and mucin domain containing molecule (Tim)-4 and CD103 in the four groups were detected by flow cytometry.The concentrations of interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) in the DCs supernatants were determined by enzyme-linked immunosorbent assay.A mixed lymphocyte culture system was established, and the stimulation index (SI) of CD4 + T cell proliferation stimulated with DCs was detected by cell counting kit 8 method.Corneal neovascularization was induced by corneal stromal suture in BALB/c mice, and the 80 mice with neovascularization in 4 quadrants growing into the middle and peripheral cornea were used as recipients.The recipient mice were randomized into imDCs group, mDCs group, RMT1-10 group, and IgG isotype control group using the random number table method, with 20 mice in each group.An injection of corresponding DCs (1×10 6 cells/100 μl) was administered to the recipient mice via the tail vein according to grouping.At 7 days following the injection, C57BL/6 mice were used as donors and penetrating keratoplasty was performed.Within one month after the operation, signs of corneal grafts rejection, including opacity, edema and neovascularization, were observed by slit lamp biomicroscopy and scored every day.At 21 days after the operation, 5 recipients selected from each group were subcutaneously injected with naive C57BL/6 splenocytes (1×10 6 cells/100 μl) behind the ear.The delayed type hypersensitivity (DTH) was evaluated by ear swelling at 24 hours after the subcutaneous injection.The use and care of experimental animals complied with the Regulations on the Management of Experimental Animals promulgated by the State Science and Technology Commission.This study protocol was approved by an Ethics Committee of the Affiliated Hospital of Chengde Medical University (No.CYFYLL2020055). Results:Compared with mDCs group, the expressions of CD80, CD86 and MHC-Ⅱ, and the percentage of Tim-4-positive cells in CD11c-positive cells were significantly decreased in RMT1-10 group, showing statistically significant differences (all at P<0.001). The percentage of Tim-4-positive cells were significantly decreased in RMT1-10 group than imDCs group, and the percentage of CD103-positive cells in RMT1-10 group was significantly higher than imDCs group, mDCs group and IgG isotype control group (all at P<0.001). The concentrations of IL-10 and TGF-β in the cell culture supernatant of RMT1-10 group were significantly higher than those of the other three groups, with statistically significant differences (all at P<0.001). There were statistically significant differences in the SI of CD4 + T cell proliferation simulated by DCs ( Fgroup=1 833.00, P<0.001; Fratio=230.40, P<0.001; Finteraction=3.06, P=0.01). The SI of DCs/CD4 + T cells ratio at 1∶5, 1∶10, 1∶20 and 1∶40 were all significantly lower in imDCs group than mDCs group, and were all significantly lower in RMT1-10 group than imDCs group (all at P<0.05). There was a statistically significant difference in corneal graft survival curve among various groups ( χ2=77.69, P<0.001). The survival rate of RMT1-10 group was significantly higher than that of imDCs group ( χ2=9.74, P=0.002), and the survival rate of imDCs group was significantly higher than that of mDCs group ( χ2=31.02, P<0.001). The ear swelling of recipient mice of positive control group, mDCs group, IgG isotype control group, imDCs group and RMT1-10 group was (503.6±17.2), (475.7±17.6), (456.2±18.8), (225.2±39.4), (118.1±12.6), and (106.4±7.4) μm, with a statistically significant difference among them ( F=377.10, P<0.001). The mice ear swelling was more serious in positive control group than mDCs group, more serious in IgG isotype control group than imDCs group, and more serious in imDCs group than RMT1-10 group (all at P<0.05). Conclusions:RMT1-10 can inhibit the rejection of high-risk corneal transplantation in mice, the mechanism of which may be attributed to inducing imDCs to transform into Tol-DCs in vitro and up-regulating the expression of TGF-β and IL-10, which promotes antigen-specific immune tolerance after adoptive transfer, thereby indirectly prolongs the survival of corneal grafts.