Yeast-derived nanoparticles remodel the immunosuppressive microenvironment in tumor and tumor-draining lymph nodes to suppress tumor growth.

Microbe-based cancer immunotherapy has recently emerged as a hot topic for cancer treatment. However, serious limitations remain including infection associated side-effect and unsatisfactory outcomes in clinic trials. Here, we fabricate different sizes of nano-formulations derived from yeast cell wall (YCW NPs) by differential centrifugation. The induction of anticancer immunity of our formulations appears to inversely correlate with their size due to the ability to accumulate in tumor-draining lymph node (TDLN). Moreover, we use a percolation model to explain their distribution behavior toward TDLN. The abundance and functional orientation of each effector component are significantly improved not only in the microenvironment in tumor but also in the TDLN following small size YCW NPs treatment. In combination with programmed death-ligand 1 (PD-L1) blockade, we demonstrate anticancer efficiency in melanoma-challenged mice. We delineate potential strategy to target immunosuppressive microenvironment by microbe-based nanoparticles and highlight the role of size effect in microbe-based immune therapeutics.

Spirulina maxima Derived Pectin Nanoparticles Enhance the Immunomodulation, Stress Tolerance, and Wound Healing in Zebrafish.

In this study, Spirulina maxima derived pectin nanoparticles (SmPNPs) were synthesized and multiple biological effects were investigated using in vitro and in vivo models. SmPNPs were not toxic to Raw 264.7 cells and zebrafish embryos up to 1 mg/mL and 200 µg/mL, respectively. SmPNPs upregulated Il 10, Cat, Sod 2, Def 1, Def 2, and Muc 1 in Raw 264.7 cells and tlr2, tlr4b, tlr5b, il1ß, tnfα, cxcl8a, cxcl18b, ccl34a.4, ccl34b.4, muc5.1, muc5.2, muc5.3, hamp, cstd, hsp70, cat, and sod1 in the larvae and adult zebrafish, suggesting immunomodulatory activity. Exposure of larvae to SmPNPs followed by challenge with pathogenic bacterium Aeromonas hydrophila resulted a two-fold reduction of reactive oxygen species, indicating reduced oxidative stress compared to that in the control group. The cumulative percent survival of larvae exposed to SmPNPs (50 µg/mL) and adults fed diet supplemented with SmPNPs (4%) was 53.3% and 76.7%, respectively. Topical application of SmPNPs on adult zebrafish showed a higher wound healing percentage (48.9%) compared to that in the vehicle treated group (38.8%). Upregulated wound healing markers (tgfß1, timp2b, mmp9, tnfα, il1ß,ccl34a.4, and ccl34b.4), enhanced wound closure, and restored pigmentation indicated wound healing properties of SmPNPs. Overall, results uncover the multiple bioactivities of SmPNPs, which could be a promising biocompatible candidate for broad range of aquatic and human therapies.

Targeting STING with cyclic di-GMP greatly augmented immune responses of glycopeptide cancer vaccines.

Cyclic di-GMP (CDG) was applied to MUC1 glycopeptide-based cancer vaccines with physical mixing and built-in (at 2'-OH of CDG) strategies for activating the STING pathway. CDG in both strategies behaved as a potent immunostimulant and contributed to high titers of IgG antibodies and the expression of multiple cytokines.

Immune Enhancement Effect of Asterias amurensis Fatty Acids through NF-κB and MAPK Pathways on RAW 264.7 Cells.

Asterias amurensis is a marine organism that causes damage to the fishing industry worldwide; however, it has been considered a promising source of functional components. The present study aimed to investigate the immune-enhancing effects of fatty acids from three organs of A. amurensis on murine macrophages (RAW 264.7 cells). A. amurensis fatty acids boosted production of immune-associated factors such as nitric oxide (NO) and prostaglandin E2 in RAW 264.7 cells. A. amurensis fatty acids also enhanced the expression of critical immune-associated genes, including iNOS, TNF-α, IL-1ß, and IL-6, as well as COX-2. Western blotting showed that A. amurensis fatty acids stimulated the NF-κB and MAPK pathways by phosphorylation of NF-κB p-65, p38, ERK1/2, and JNK. A. amurensis fatty acids from different tissues resulted in different levels of NF-κB and MAPK phosphorylation in RAW 264.7 cells. The results increase our understanding of how A. amurensis fatty acids boost immunity in a physiological system, as a potential functional material.

Colecalciferol regula os parâmetros hematológicos e a produção de citocinas pró-inflamatórias renais em camundongos diabéticos e nas células RAW 264. 7 / Colecalciferol regulates haematological parameters and the production of renal proinflammatory cytokines in diabetic mice and RAW 264. 7 cells

Os efeitos causados pelo tratamento em conjunto da insulina e do colecalciferol em indivíduos diabéticos não estão completamente elucidados. O presente trabalho avaliou o efeito de ambos os hormônios nos rins, no fígado, no coração e nos parâmetros hematológicos de camundongos machos (C57BL/6) sadios e diabéticos, bem como a ação do colecalciferol (in vitro) na resposta imunológica desenvolvida pelas células RAW 264.7 e pelos macrófagos peritoneais (MP) após estímulo com lipopolissacarídeo (LPS). Após dez dias da administração da aloxana (60 mg/kg), animais diabéticos exibiram redução do ganho de peso corporal e hiperglicemia quando comparados aos animais que receberam salina. No sétimo dia do período experimental, foi verificado que animais diabéticos que não receberam nenhum hormônio, em relação aos não diabéticos, exibiram redução do peso corporal, dos níveis de hemoglobina (Hb), hematócrito, hematimetria, insulina, TNF-α e IL-6 (coração) e aumento da glicemia, da relação peso corpóreo/peso rim esquerdo, das concentrações séricas de ureia, creatinina, Fosfatase Alcalina (FAL), Lactato desidrogenase (LDH) e lactato, fator de necrose tumoral (TNF)-α, interleucina (IL)-6 e IL-10 (no rim); o tratamento com insulina (1 UI/300 mg/dL glicemia), em relação aos animais diabéticos não tratados, promoveu aumento do peso corporal, das concentrações séricas de insulina e redução da glicemia, das concentrações séricas de ureia e da razão TNF-α/IL-10 (coração); o tratamento com colecalciferol (800 UI/dia), em relação aos animais diabéticos não tratados, promoveu aumento das concentrações séricas de 25-hidroxicolecalciferol [25(OH)D], Hb, hematócrito, hematimetria, IL-10 (coração) e reduziu IL-6, IL-10, TNF-α e EPO (rim); os animais diabéticos tratados com insulina, em relação aos animais diabéticos suplementados com colecalciferol apresentaram aumento do peso corpóreo, de ureia sérica, IL-6 e TNF-α (coração) e redução da glicemia, das concentrações séricas de lactato, de IL-6, TNF-α, IL-10 e EPO (rim); os animais -que receberam ambos os hormônios, em relação aos animais tratados com insulina, apresentaram aumento sérico de insulina e lactato; os animais diabéticos que receberam ambos os hormônios, em relação aos animais diabéticos tratados com colecalciferol, exibiram aumento sérico de 25(OH)D, de insulina, além da redução das concentrações de IL-10, da razão de TNF-α/IL-10 e TNF-α/IL-6 (coração); animais diabéticos que receberam ambos os hormônios, em relação aos diabéticos não suplementados com colecalciferol, exibiram: aumento de insulina sérica e redução das concentrações séricas de ureia e das razões renal e hepática de TNF-α/IL-6; células RAW 264.7 estimuladas pelo LPS e tratadas com 100 nM colecalciferol exibiram maior expressão da CYP27B1 e redução na liberação de mediadores inflamatórios quando comparadas ao grupo estimulado pelo LPS. Entretanto, não foi observado o mesmo efeito nos MP. Em conjunto, os resultados sugerem que: 1) em animais diabéticos, o colecalciferol pode modular parâmetros hematológicos e que a insulina pode melhorar a função renal, bem como a recuperação do peso corporal; 2) o colecalciferol pode ser metabolizado pelas células RAW 264.7 e modular a resposta imunológica desencadeada pelo LPS

The effects caused by the treatment of insulin and cholecalciferol in diabetic subjects are not completely elucidated. The present study evaluated the effect of both hormones on the kidneys, liver, heart and hematological parameters of healthy and diabetic male mice (C57BL/6), as well as the action of cholecalciferol (in vitro) on the immune response developed by the cells RAW 264.7 and peritoneal macrophages (MP) after stimulation with lipopolysaccharide (LPS). After ten days of alloxan administration (60 mg/kg), diabetic animals exhibited a reduction in body weight gain and hyperglycemia when compared to animals that received saline. On the seventh day of the experimental period, it was verified that diabetic animals that did not receive any hormones, in relation to non-diabetics, showed reduction of body weight, hemoglobin (Hb), hematocrit, hematimetry, insulin, TNF-α and IL- 6 (heart) and increased glycemia, body weight / left kidney weight, serum urea, creatinine, Phosphatase Alkaline, lactate dehydrogenase (LDH) and lactate levels, tumor necrosis factor (TNF) interleukin (IL) -6 and IL-10 (in the kidney); diabetic mice treated with insulin (1 IU / 300 mg/dL glycemia) in relation to untreated diabetic animals promoted increased body weight, serum insulin levels and blood glucose lowering, serum urea levels and TNF-α ratio / IL-10 (heart); diabetic animals treated with cholecalciferol (800 IU/day), in relation to untreated diabetic animals, exhibited increased serum levels of 25-hydroxycholecalciferol [25 (OH) D], Hb, hematocrit, hematimetry, IL-10 (heart) and reduced IL-6, IL-10, TNF-α and EPO (kidney);insulin-treated diabetic animals compared to diabetic animals supplemented with cholecalciferol exhibited an increase of body weight, serum urea, IL-6 and TNF-α (heart) and a reduction of glycaemia, serum lactate levels, IL-6, TNF- α, IL-10 and EPO (kidney); animals that received both hormones, compared to animals treated with insulin exhibited an increase of insulin and lactate serum levels; diabetic animals that received both hormones, compared to diabetic animals treated with cholecalciferol, exhibited an increase of 25(OH)D and insulin serum levels, and a reduction of IL-10, TNF-α/IL-10 and TNF-α/IL-6 ratios (heart); diabetic animals that received both hormones, compared to diabetic animals not supplemented with cholecalciferol, exhibited an increase of insulin and reduced urea serum levels and reduced renal and hepatic TNF-α/IL-6 ratios; LPS-stimulated RAW 264.7 cells and treated with 100 nM cholecalciferol exhibited greater CYP27B1 expression and reduced release of inflammatory mediators when compared to the LPS-stimulated group. However, the same effect was not observed in PM. Taken together, the results suggest that: 1) in diabetic animals, cholecalciferol may modulate hematological parameters and that insulin may improve renal function as well as recovery of body weight; 2) cholecalciferol can be metabolized by RAW 264.7 cells and modulate the immune response triggered by LPS

Immunomodulatory effects of soluble factors secreted by feline adipose tissue-derived mesenchymal stem cells.

Mesenchymal stem cells (MSCs) have immunomodulatory functions and differentiation capacity, and their clinical use is increasing in veterinary species. Although MSCs have been applied in the treatment in various inflammatory diseases, mechanistic research on feline MSCs is lacking. Accordingly, in this study, we aimed to investigate the immunomodulatory mechanisms of MSCs isolated from feline adipose tissue (fATMSCs). fATMSCs from healthy cats were cultured in an appropriate manner and cocultured with transwell-separated allogeneic feline peripheral blood mononuclear cells (fPBMCs) and RAW264.7 murine macrophages. After 48h of coculture, RNA was extracted from RAW264.7 cells and fPBMCs. Cytokine expression in these cells was measured using quantitative real-time polymerase chain reaction (qRT-PCR) and compared according to the presence of fATMSCs. The mRNA levels of pro-inflammatory cytokines, e.g., tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase, and interleukin (IL)-1ß, were significantly decreased in cocultures of mitogen-stimulated RAW264.7 cells with fATMSCs compared with that in the RAW264.7 cells control group. Additionally, changes in the expression of mRNAs extracted from fPBMCs were as follows: pro-inflammatory TNF-α, interferon-γ, and IL-6 were decreased, and anti-inflammatory IL-10 was increased during coculture of mitogen-stimulated allogeneic fPBMCs with fATMSCs. We also extracted RNA and collected supernatants from fATMSCs during transwell culture for measurement of the expression and secretion of soluble factors by qRT-PCR and enzyme-linked immunosorbent assays, respectively. The mRNA expression of immunomodulatory factors from fATMSCs, including cyclooxygenase-2 (COX-2), transforming growth factor (TGF)-ß, indoleamine-2,3-dioxygenase (IDO) and hepatocyte growth factor, increased in the presence of RAW264.7 cells. Similarly, TGF-ß, COX-2, and IDO mRNA expression and prostaglandin E2 (PGE2) secretion from fATMSCs increased in the presence of allogeneic fPBMCs. Finally, we measured the viability of fPBMCs under various conditions. Cell viability decreased in fPBMCs suspended in fATMSC-derived conditioned medium, and this reduction was alleviated in the group supplemented with NS-398 a PGE2 inhibitor. Our data suggested that soluble factors, including PGE2, secreted by fATMSCs played an important role in the immunomodulatory effects of these cells. These findings may be helpful in the application of fATMSCs to feline patients with immune-related diseases.

Th2-related immune responses by the Brucella abortus cellular antigens, malate dehydrogenase, elongation factor, and arginase.

Brucellosis is an important zoonotic disease caused by Brucella species. The disease is difficult to control due to the intracellular survival of the bacterium and the lack of precise understanding of pathogenesis. Despite of continuous researches on the pathogenesis of Brucella spp. infection, there is still question on the pathogenesis, especially earlier immune response in the bacterial infection. Malate dehydrogenase (MDH), elongation factor (Tsf), and arginase (RocF), which showed serological reactivity, were purified after gene cloning, and their immune modulating activities were then analyzed in a murine model. Cytokine production profiles were investigated by stimulating RAW 264.7 cells and naïve splenocytes with the three recombinant proteins. Also, immune responses were analyzed by ELISA and an ELIspot assay after immunizing mice with the three proteins. Only TNF-α was produced in stimulated RAW 264.7 cells, whereas Th1-related cytokines, IFN-γ and IL-2, were induced in naïve splenocytes. In contrast, Th2-type immune response was more strongly induced in antigen-secreting cells in the splenocytes obtained 28 days after immunizing mice with the three proteins, as were IgM and IgG. The induction of Th2-related antibody, IgG1, was higher than the Th1-related antibody, IgG2a, in immunized mice. These results suggest that the three proteins strongly induce Th2-type immune response in vivo, even though Th1-related cytokines were produced in vitro.

The Matrine Derivate MASM Prolongs Survival, Attenuates Inflammation, and Reduces Organ Injury in Murine Established Lethal Sepsis.

BACKGROUND: MASM, a novel derivative of matrine, has inhibitory effects on activation of macrophages, dendritic cells, and hepatic stellate cells and binds to ribosomal protein S5 (RPS5). This study was designed to evaluate the effect of MASM on murine-established lethal sepsis and its mechanisms. METHODS: Mouse peritoneal macrophages and RAW264.7 cells that were infected with recombinant lentiviruses encoding shRPS5 were incubated with lipopolysaccharide (LPS) in the absence or presence of MASM in vitro. Endotoxemia induced by LPS injection and sepsis induced by cecal ligation and puncture was followed by MASM treatment. RESULTS: MASM markedly attenuated LPS-induced release and messenger RNA expression of tumor necrosis factor α, interleukin 6, and NO/inducible NO synthase in murine peritoneal macrophages and RAW264.7 cells. Meanwhile, MASM inhibited LPS-induced activation of nuclear factor κB and MAPK pathways. Consistently, RPS5 suppressed LPS-induced inflammatory responses and at least in part mediated the antiinflammatory effect of MASM in vitro. Remarkably, delayed administration of MASM could significantly reduce mortality in mouse sepsis models, which was associated with the reduction in the inflammatory response, the attenuation in multiple organ injury, and the enhanced bacterial clearance. CONCLUSIONS: MASM could be further explored for the treatments of sepsis, especially for administration later after the onset of sepsis.

Scavenger receptor SREC-I mediated entry of TLR4 into lipid microdomains and triggered inflammatory cytokine release in RAW 264.7 cells upon LPS activation.

Scavenger receptor associated with endothelial cells I (SREC-I) was shown to be expressed in immune cells and to play a role in the endocytosis of peptides and antigen presentation. As our previous studies indicated that SREC-I required intact Toll-like receptor 4 (TLR4) expression for its functions in tumor immunity, we examined potential interactions between these two receptors. We have shown here that SREC-I became associated with TLR4 on binding bacterial lipopolysaccharides (LPS) in RAW 264.7 and HEK 293 cells overexpressing these two receptors. The receptors then became internalized together in intracellular endosomes. SREC-I promoted TLR4-induced signal transduction through the NF-kB and MAP kinase pathways, leading to enhanced inflammatory cytokine release. Activation of inflammatory signaling through SREC-I/TLR4 complexes appeared to involve recruitment of the receptors into detergent-insoluble, cholesterol-rich lipid microdomains that contained the small GTPase Cdc42 and the non-receptor tyrosine kinase c-src. Under conditions of SREC-I activation by LPS, TLR4 activity required Cdc42 as well as cholesterol and actin polymerization for signaling through NF-kB and MAP kinase pathways in RAW 264.7 cells. SREC-I appeared to respond differently to another ligand, the molecular chaperone Hsp90 that, while triggering SREC-I-TLR4 binding caused only faint activation of the NF-kB pathway. Our experiments therefore indicated that SREC-I could bind LPS and might be involved in innate inflammatory immune responses to extracellular danger signals in RAW 264.7 cells or bone marrow-derived macrophages.

Interactions of Streptococcus iniae with phagocytic cell line.

Streptococcus iniae has become one of the most serious aquatic pathogens in the last decade, causing large losses in wild and farmed fish worldwide. There is clear evidence that this pathogen is capable not only of causing serious disease in fish but also of being transferred to and infecting humans. In this study, we investigate the interaction of S. iniae with two murine macrophage cell lines, J774-A1 and RAW 264.7. Cytotoxicity assay demonstrated significant differences between live and UV-light killed IUSA-1 strains. The burst respiratory activity decreased to baseline after 1 and 4 h of exposure for J774-A1 and RAW 264.7, respectively. Immunofluorescent and ultrastructural study of infected cells confirmed the intracellular localization of bacteria at 1 h and 24 h post-infection. Using qRT-PCR arrays, we investigated the changes in the gene expression of immune relevant genes associated with macrophage activation. In this screening, we identified 11 of 84 genes up-regulated, we observed over-expression of pro-inflammatory response as IL-1α, IL-1ß, and TNF-α, without a good anti-inflammatory response. Present findings suggest a capacity of S. iniae to modulate a mammalian macrophages cell lines to their survival and replication intracellular, which makes this cell type as a reservoir for continued infection.