Splenic Lymphocytes Research Articles

Matrine combined with Osthole inhibited the PERK apoptosis of splenic lymphocytes in PCV2-infected mice model

BackgroundPorcine circovirus type 2 (PCV2) is one of the major pathogens commonly found in pigs, which causes immunosuppression and apoptosis. Vaccination and a single drug cannot totally prevent and treat PCV2 infection. Our previous in vitro study reported that the synergistic anti-PCV2 effect of Matrine and Osthole was better than that of Matrine or Osthole alone, This study was aimed to evaluate the synergistic anti-PCV2 effect as well as the underline molecular mechanism of Matrine and Osthole in Kunming (KM) mice model infected with PCV2. KM mice were randomly divided into 8 groups namely control group, PCV2 infected, Matrine combined with Osthole high dose treatment (40 mg/kg + 12 mg/kg), medium dose treatment (20 mg/kg + 6 mg/kg), low dose treatment (10 mg/kg + 3 mg/kg), Matrine treatment (40 mg/kg), Osthole treatment (12 mg/kg) and Ribavirin positive control (40 mg/kg) groups. PCV2 was intraperitoneally (i.p.) injected in all mice except the control group. 5 days of post-infection (dpi), mice in different treatment groups were injected i.p. with various doses of Matrine, Osthole and Ribavirin once daily for the next 5 consecutive days.ResultsThe synergistic inhibitory effect of Matrine and Osthole on PCV2 replication in mouse liver was significantly heigher than that of Matrine and Osthole alone. The expression of GRP78, p-PERK, p-eIF2α, ATF4, CHOP, cleaved caspase-3 and Bax proteins were significantly reduced, while that of Bcl-2 was significantly increased in Matrine combined with Osthole groups, which alleviated the pathological changes caused by PCV2, such as interstitial pneumonia, loss of spleen lymphocytes, infiltration of macrophages and eosinophils.ConclusionsThe synergistic anti-apoptotic effect of Matrine and Osthole was better than their alone effect, Both Matrine and Osthole had directly inhibited the expression of PCV2 Cap and the apoptosis of spleen cells induced by PCV2 Cap through the PERK pathway activated by endoplasmic reticulum (ER) GRP78. These results provided a new insight to control PCV2 infection and provide good component prescription candidate for the development of novel anti-PCV2 drugs.

Immunomodulatory effects of complex probiotics on the immuno-suppressed mice induced by cyclophosphamide.

Previous studies have reported the beneficial effects of Bifidobacterium animalis subsp. lactis XLTG11, Lacticaseibacillus casei Zhang, and Lactiplantibacillus plantarum P8, respectively. However, studies on the immunomodulatory enhancing effects of three complex probiotics have not been conducted. The aim of our study is to investigate the immunomodulatory effects of complex probiotics effect on the immunosuppressed mice induced by cyclophosphamide (CTX). An immunocompromised mouse model was established by intraperitoneal injection of cyclophosphamide, which was gavage of different doses of complex probiotics and levamisole hydrochloride. The splenic and thymic indices, intestinal barrier, leukocyte and lymphocyte counts, percentage of splenic lymphocyte subpopulations, cytokine levels, and gut microbiota were determined. Results showed that the complex probiotics significantly elevated the spleen and thymus indices, increased the villi and crypt depth and the goblet cells. The leukocyte and lymphocyte counts and the percentage of splenic lymphocyte subpopulations in the CTX-treated mice were significantly elevated by the complex probiotics. In addition, the cytokines (IL-6, IL-10, IL-1β, and IFN-γ) were significantly increased after complex probiotic treatment. The complex probiotics restored the gut microbiota structure to the pattern of the control group by reducing the ratio of Firmicutes/Bacteroidetes and enhancing the relative abundances of specific microbiota that produced short-chain fatty acids. This study provides theoretical support for the immunity-enhancing function of the complex probiotics as well as a pharmacological basis for its further development and utilization.

PLZF promotes the development of asthma tolerance via affecting memory phenotypes of immune cells.

Clarifying the pathogenesis of asthma and/or identifying the specific pathway underlying oral asthma tolerance (OT) would be of great significance. In our previous study, promyelocytic leukemia zinc finger (PLZF), which reportedly regulates memory phenotypes, was found to promote ovalbumin (OVA)-induced OT. Therefore, this study aimed to explore the regulatory effects of PLZF on memory phenotypes in asthma and OT mouse models. We found that Zbtb16 (encoding PLZF) and PLZF+ cells were highly increased in OT lungs compared with asthmatic lungs. PLZF was co-expressed with GATA3, and IL-4+PLZF+ cells were significantly lower in OT lungs than in asthmatic lungs. Notably, memory cells were decreased in OT mice, and these mice had PLZF+ cells that expressed lower levels of CD44 than those of asthmatic mice. When Zbtb16 was overexpressed in splenic lymphocytes, the number of CD44+ cells decreased. There were increased memory cells in splenic lymphocytes after treatment with the supernatant of OVA-treated airway epithelial cells; however, this was reversed by Zbtb16 overexpression. Early respiratory syncytial virus infection increased memory cells and reduced PLZF+ cells in the OT mice. Collectively, these results indicate that PLZF may reduce the proportion of memory cells, thereby, promoting the establishment of OT.

Trojan-horse silk fibroin nanocarriers loaded with a re-call antigen to redirect immunity against cancer

BackgroundThe current challenge for immunotherapies is to generate effective antitumor immunity. Since tumor immune escape mechanisms do not impact pre-existing and consolidated immune responses, we tested the hypothesis of redirecting...

A polysaccharide from Pleurotus citrinopileatus mycelia enhances the immune response in cyclophosphamide-induced immunosuppressed mice via p62/Keap1/Nrf2 signal transduction pathway

The manuscript aimed to study the immunoregulatory activity and the mechanism of the polysaccharide (CMP) from Pleurotus citrinopileatus mycelia. The mice were divided into normal group, model group, different dosage of CMP (50, 100 and 200 mg/kg, respectively) groups and levamisole hydrochloride treated group. The results showed that, compared with the model group, CMP could significantly improve the auricle swelling rate, half hemolysis value and phagocytic index in mice. The indices of immune organs were raised, and tissue damage of spleen was relieved. Splenic Th1 cells were decreased, while Th2 cells were increased, furthermore the proliferation of splenic lymphocytes and the cytotoxicity of NK cells were increased. The levels of interleukin-12 (IL-12), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in spleen were decreased, while interleukin-4 (IL-4) and interleukin-10 (IL-10) were increased. In serum and spleen, the levels of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities were increased, while the level of malondialdehyde (MDA) was decreased. And the levels of Immunoglobulin were also increased. Western blot showed that CMP had immunoregulatory activity by activating Nrf2, Keap1, p62, HO-1, and NQO1 in the p62/Keap1/Nrf2 signaling pathway. The study proved that CMP could be used as a biological Immune regulating agent.

Essential oil from Prunella vulgaris L. as a valuable source of bioactive constituents: In vitro anti-bacterial, anti-viral, immunoregulatory, anti-inflammatory, and chemical profiles

• We identified 56 chemical components of PVO and fatty acids are the most. • PVO had an antibacterial effect on gram-negative bacteria and gram-positive bacteria. • PVO had an antiviral effect. • PVO had a significant anti-inflammatory effect. • PVO has dual immunomodulatory effects. Our preliminary results suggested a favorable therapeutical effect of essential oil from Prunella vulgaris L. (PVO) on pelvic inflammation. In this study, we further analyzed the chemical components of PVO through gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS), and its anti-bacterial, anti-inflammatory, and immunoregulatory properties. Fifty-six chemical components were identified with GC-MS, most of which were fatty acids. The positive and negative ion modes of LC-MS were used to detect 48 and 37 compounds with content above 0.1%, respectively, most of which were terpenoids and lipids. The anti-bacterial experiment revealed that PVO could strongly inhibit both gram-negative and gram-positive bacteria. It had a significant inhibiting effect on influenza virus neuraminidase, with an inhibition ratio of over 50%. Besides, PVO dramatically inhibited the NO release and the levels of IL-6 in RAW264.7 cells induced by LPS. Moreover, immunological results indicated that PVO could synergistically facilitate concanavalin A (ConA) to stimulate the secretion of Th1 and Th2 cytokines from the splenic lymphocytes of mice but also regulate the Th1/Th2 balance to exert dual immunoregulatory effects. Generally, these results proved the anti-bacterial, anti-inflammatory, and immunoregulatory effects of PVO, thus providing a reference for the application of PVO as a food or drug.

Abstract A074: Developing a novel in vivo model of pancreatic ductal adenocarcinoma using primary tumor samples and humanised mouse models

Abstract Pancreatic cancer (PDAC) remains one of the most lethal malignancies due to its late diagnosis and poor response to treatment. Preclinical models reflecting the uniquely complex structure of PDAC cells and the surrounding tumor microenvironment (TME) are required to ensure translational results. PDAC organoids, ex vivo 3D models of primary tumor cells, form an exciting preclinical model that reflects the complexity of PDAC. Tumor organoids co-cultured with stromal and immune cells have been previously explored in vitro but have thus far remained limited in any in vivo capacity. We therefore aimed to establish and characterize in vitro co-cultured PDAC organoids using primary human PDAC tumor samples plus autologous peripheral or splenic lymphocytes. Subsequent preliminary in vivo models have been established by engrafting co-cultured PDAC organoids and PDAC cancer associated fibroblasts into immunocompromised mice. The pilot data assessed retention, growth kinetics and metastatic potential and will subsequently form the foundation for comparable experiments using autologous humanized mouse models. This humanized mouse model, consisting of autologous human malignant, stromal and immune compartments, will add to the existing repertoire of preclinical models by more closely representing the entire tumor volume. In vitro and in vivo data compared to other preclinical models. Additional preliminary therapeutic response data may provide translational value and warrant further evaluation. Citation Format: Alexander J. P. Fulton, Kourosh Saeb-Parsy, Bristi Basu. Developing a novel in vivo model of pancreatic ductal adenocarcinoma using primary tumor samples and humanised mouse models [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A074.

Development and Efficacy Evaluation of a Novel Nano-Emulsion Adjuvant for a Foot-and-Mouth Disease Virus-like Particles Vaccine Based on Squalane.

The successful development of foot-and-mouth disease virus-like particles (FMD-VLPs) has opened a new direction for researching a novel subunit vaccine for foot-and-mouth disease (FMD). Therefore, it is urgent to develop an adjuvant that is highly effective and safe to facilitate a better immune response to be pair with the FMD-VLP vaccine. In this research, we prepared a new nano-emulsion adjuvant based on squalane (SNA) containing CpG using the pseudo-ternary phase diagram method and the phase transformation method. The SNA consisted of Span85, Tween60, squalane, polyethene glycol-400 (PEG400) and CpG aqueous solution. The average particle diameter of the SNA was about 95 nm, and it exhibited good resistance to centrifugation, thermal stability, and biocompatibility. Then, SNA was emulsified as an adjuvant to prepare foot-and-mouth disease virus-like particles vaccine, BALB/c mice and guinea pigs were immunized, and we evaluated the immunization effect. The immunization results in mice showed that the SNA-VLPs vaccine significantly increased specific antibody levels in mice within 4 weeks, including higher levels of IgG1 and IgG2a. In addition, it increased the levels of IFN-γ and IL-1β in the immune serum of mice. Meanwhile, guinea pig-specific and neutralizing antibodies were considerably increased within 4 weeks when SNA was used as an adjuvant, thereby facilitating the proliferation of splenic lymphocytes. More importantly, in guinea pigs immunized with one dose of SNA-VLPs, challenged with FMDV 28 days after immunization, the protection rate can reach 83.3%, which is as high as in the ISA-206 control group. In conclusion, the novel squalane nano-emulsion adjuvant is an effective adjuvant for the FMD-VLPs vaccine, indicating a promising adjuvant for the future development of a novel FMD-VLPs vaccine.

Studies on the metabolism and mechanism of acteoside in treating chronic glomerulonephritis

Ethnopharmacological relevanceActeoside (ACT) is the main ingredient derived from the leaves of Rehmannia glutinosa (Dihuangye). Dihuangye has the function of clearing heat, replenishing qi and activating blood, nourishing yin and tonifying kidney in traditional Chinese medicine. Recent studies have demonstrated that Dihuangye can be used to treat nephritis and ACT is a promising antinephritic agent. Aim of the studyTo clarify the metabolites of ACT in biological samples and investigate the renoprotective effect and mechanism of ACT in rats with chronic glomerulonephritis (CGN). Materials and methodsIn this study, the biotransformation of ACT in rat biological samples was clarified by quadrupole time-of-flight tandem mass spectrometry. The metabolites were validated by urine samples in nephropathy model rats. The effect of ACT and its metabolites was evaluated by glomerular podocyte injury due to high glucose. Based on an analysis of the ingredients in vivo, the potential therapeutic targets in the treatment of CGN were investigated by using network pharmacological analysis and molecular docking. Then, the renoprotective effect and mechanism of ACT were determined in rats in a passive Heymann nephritis (PHN) model. ResultsA total of 49 metabolites of ACT were detected and identified. Meanwhile, 21 metabolites were detected in nephropathy model rats. ACT was absorbed rapidly and transferred from the kidney, and the metabolites were eliminated via urine. The whole process lasted approximately 8 h. ACT had a significant protective effect on glomerular podocytes damaged by high glucose and 3,4-dihydroxyphenylacetic acid might be the main metabolite of ACT underlying its functions in vivo. The network pharmacology and molecular docking results showed 84 ACT-CGN targets, among which MAPK1, HRAS, AKT1, EGFR, and others were a highly correlated. In the PHN rat model, ACT significantly reduced the 24-h urine protein and serum creatinine concentrations, suppressed the leukocyte CD18 expression levels, decreased the serum tumor necrosis factor α (TNF-α) levels and tended to reduce serum interleukin 6 (IL-6) levels. ACT significantly reduced the platelet aggregation rate and inhibited the proliferative activity of splenic lymphocytes in response to the mitogen concanavalin A. Meanwhile, ACT inhibited transforming growth factor-β and fibronectin expression in renal tissues and dose-dependently inhibited TNF-α and IL-6 production in RAW264.7 mouse macrophages at doses ranging from 1.8 to 1330 μg/mL. ConclusionsACT had therapeutic effects on PHN rats, and its mechanism might be related to the inhibition of intercellular or intercellular-matrix adhesion, suppression of inflammatory response, regulation of immune function, improvement of tissue hemodynamics and hemorheology, and relief of fibrotic lesions.

Antitumor effects of polysaccharides from Tetrastigma hemsleyanum Diels et Gilg via regulation of intestinal flora and enhancing immunomodulatory effects in vivo.

Tetrastigma hemsleyanum Diels et Gilg is a traditional Chinese herbal medicine with high medicinal value, and antitumor, antioxidant and anti-inflammatory biological activities. However, while several studies have focused on flavonoids in Tetrastigma hemsleyanum tubers, there are few studies on the enhanced immune effect of Tetrastigma hemsleyanum polysaccharides (THP). In this study, we evaluated the antitumor effect of THP in a lung tumor model and explored the mechanism of antitumor activity through intestinal flora. In addition, a cyclophosphamide (CTX)-induced immunosuppression model was used to declare the immunomodulatory effect of THP in the immunosuppressive state induced by antitumor drugs. The results showed that THP increased the content of ileum secreted immunoglobulin A (SIgA) and cecum short-chain fatty acids (SCFAs) and improved microbial community diversity, regulating the relative abundance of dominant microbiota flora from the phylum level to the genus level, and recovering the intestinal microflora disorder caused by tumors. Additionally, THP can increase the organ indices and improve immune organ atrophy. THP can upregulate routine blood counts and stimulate the production of the serum cytokines. THP also promoted the macrophage phagocytic index, NK-cell activation, and complement and immunoglobulin (IgG, IgA, IgM) levels. The detection of Splenic lymphocyte proliferation and T lymphocyte subsets also sideways reflects that THP can restore CTX-induced immune inhibition in mice. In conclusion, this study suggests that THP can effectively achieve the enhanced antitumor effects, regulate gut microbiota and improve the immunosuppression induced by antitumor drugs. Therefore, THP can enhance the immune capacity and provide novel immunomodulatory and antineoplastic adjuvant agents.

Immunomodulatory Effects of Chicken Broth and Histidine Dipeptides on the Cyclophosphamide-Induced Immunosuppression Mouse Model.

The carnosine and anserine, which represent histidine dipeptides (HD), are abundant in chicken broth (CB). HD are endogenous dipeptide that has excellent antioxidant and immunomodulatory effects. The immunomodulatory effect of CB hydrolysate (CBH) and HD in cyclophosphamide (CTX)-induced immunosuppressed mice was examined in this study. CBH and HD were given to mice via oral gavage for 15 days, accompanied by intraperitoneal CTX administration to induce immunosuppression. CBH and HD treatment were observed to reduce immune organ atrophy (p < 0.05) and stimulate the proliferation of splenic lymphocytes (p < 0.05) while improving white blood cell, immunoglobulin M (IgM), IgG, and IgA levels (p < 0.05). Moreover, CBH and HD strongly stimulated interleukin-2 (IL-2) and interferon-gamma (IFN-γ) production by up-regulating IL-2 and IFN-γ mRNA expression (p < 0.05) while inhibiting interleukin-10 (IL-10) overproduction and IL-10 mRNA expression (p < 0.05). In addition, CBH and HD prevented the inhibition of the nitric oxide (NP)/cyclic guanosine monophosphate-cyclic adenosine monophosphate (cGMP-cAMP)/protein kinase A (PKA) signaling pathway (p < 0.05). These results indicate that CBH and HD have the potential to prevent immunosuppression induced by CTX. Our data demonstrate that CBH can effectively improve the immune capacity of immunosuppressed mice similar to the same amount of purified HD, which indicates that CBH plays its role through its own HD.

Frequencies of Chromosome Aberrations are Lower in Splenic Lymphocytes from Mice Continuously Exposed to Very Low-Dose-Rate Gamma Rays Compared with Non-Irradiated Control Mice.

Chromosome aberrations have been one of the most sensitive and reliable biomarkers of exposure to ionizing radiation. Using the multiplex fluorescence in situ hybridization (M-FISH) technique, we compared the changes, over time, in the frequencies of translocations and of dicentric chromosomes in the splenic lymphocytes from specific pathogen-free (SPF) C3H/HeN female mice continuously exposed to 0.05 mGy/day (18.25 mGy/year) gamma rays for 125 to 700 days (total accumulated doses: 6.25-35 mGy) with age-matched non-irradiated controls. Results show that the frequencies of translocations and of dicentric chromosomes increased significantly over time in both irradiated and non-irradiated control mice, and that the frequencies were significantly lower, not higher, in the irradiated mice, which differs from our previous reports of increased chromosome aberration frequencies at higher radiation dose rates of 1 mGy/day and 20 mGy/day. These results will be useful when considering the radiation risk at very low-dose rates comparable to regulatory dose limits.

Frequencies of Chromosome Aberrations are Lower in Splenic Lymphocytes from Mice Continuously Exposed to Very Low-Dose-Rate Gamma Rays Compared with Non-Irradiated Control Mice.

Chromosome aberrations have been one of the most sensitive and reliable biomarkers of exposure to ionizing radiation. Using the multiplex fluorescence in situ hybridization (M-FISH) technique, we compared the changes, over time, in the frequencies of translocations and of dicentric chromosomes in the splenic lymphocytes from specific pathogen-free (SPF) C3H/HeN female mice continuously exposed to 0.05 mGy/day (18.25 mGy/year) gamma rays for 125 to 700 days (total accumulated doses: 6.25-35 mGy) compare with age-matched non-irradiated controls. Results show that the frequencies of translocations and of dicentric chromosomes increased significantly over time in both irradiated and non-irradiated control mice, and that the frequencies were significantly lower, not higher, in the irradiated mice, which differs from our previous reports of increased chromosome aberration frequencies at higher radiation dose rates of 1 mGy/day and 20 mGy/day. These results will be useful when considering the radiation risk at very low-dose rates comparable to regulatory dose limits.

Effect of velvet antler on the immune activity of cyclophosphamide-induced immunosuppressed mice

ABSTRACT To study the antioxidant and immune protection activity of velvet antler (VA) in cyclophosphamide-induced immunocompromised mice, BALB/c mice were intragastrically administered 100, 300, or 500 mg/(kg·d) VA for 30 days, and were intraabdominally injected with cyclophosphamide to create a hypoimmune murine model. Cellular immunity, macrophage phagocytic activity, natural killer (NK) cell activity, white blood cell count, splenic lymphocyte subsets and the mRNA expression levels of serum cytokines were analysed. We found that the IC50 for removing 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), OH, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals of VA were 0.476, 4.33, and 37.92 mg/mL, respectively. VA could enhance innate and adaptive immunity of mice by improving cellular immunity, macrophage phagocytic ability, and NK cell activity; promoting the production of IL-4, IFN-γ, TNF-α and other cytokines; increasing the content and ratio of lymphocyte subsets. These results indicate that VA has good antioxidant activity and can improve the immune function of cyclophosphamide-induced immunodeficient mice.

Early-life maternal deprivation affects the mother-offspring relationship in domestic pigs, as well as the neuroendocrine development and coping behavior of piglets.

Early-life adversity may have programming effects on the psychological and physiological development of offspring. Domestic pigs (Sus scrofa) are an excellent model species for studying these effects because of their many physiological similarities to humans. Piglets from 10 sows were subjected to daily 2-h maternal deprivation on postnatal days (PND) 2–15 alone (DA) or in a group of littermates (DG). Control piglets (C) from 10 sows stayed with their mothers. Mother-offspring interaction, milk oxytocin, and cortisol were analyzed. An open-field/novel-object (OF/NO) test was performed with piglets on PNDs 16 and 40. Plasma cortisol and immune parameters were determined on PND 5 and 16. Two piglets from each group and sow were sacrificed on PND 20 and stress-related gene expression in the limbic system and prefrontal cortex (PFC), as well as splenic lymphocyte proliferative abilities, were examined. The milk cortisol of sows increased during the first separation of mother and offspring on the second day of lactation, whereas milk oxytocin did not change. The increase in cortisol by the OF/NO test on PND 16 was greater in C piglets than in DA and DG ones. DA piglets showed less agitated behavior than DG and C piglets in the OF/NO test at PND 16, but appeared more fearful. On PND 40, DA piglets showed more arousal than DG and C piglets in the OF/NO test. Neither plasma IgA nor N/L ratios in blood nor mitogen-induced proliferation of spleen lymphocytes were affected by deprivation. We found a higher mRNA expression of CRHR1 in the hypothalamus and a higher expression of MR in the hippocampus in DA piglets than in DG ones. The expression of GR, MR, and CRHR1 genes in the PFC was reduced by maternal deprivation, however, the expression of arginine vasopressin and oxytocin receptors was not affected. Repeated maternal deprivation induces sustained effects on stress reactivity and behavior of domestic piglets. Some of these effects were buffered by the presence of littermates. In addition, we found sex-specific differences in behavior and gene expression.

PH-responsive Astragalus polysaccharide-loaded PLGA nanoparticles as an adjuvant system to improve immune responses

Modern medical science believes that astragalus polysaccharides (APS) have the efficacy of strengthening immune system, while their peculiarities greatly reduced clinical applications. Poly(lactic-co-glycolic acid) (PLGA) is a synthetic carrier material with outstanding biochemical properties. In this study, PLGA materials were used to prepare the novel pH-responsive targeting drug delivery carriers which were encapsulated APS inside. The OVA-loaded pH-responsive APS-encapsulated PLGA Nanoparticles (OVA-loaded pH-responsive APSPs) and the OVA-loaded APSPs were constructed by multiple emulsion solvent evaporation method. Characterization and immunoenhancing activities of PLGA nanoparticles (NPs) were evaluated in vitro and in vivo. The size of NPs ranged from 142.6 to 194.6 nm, and all NPs were negatively charged. Additionally, pH-responsive APSPs shown violent release behaviors in an acidic environment. pH-responsive APSPs had low cytotoxicity, and significantly enhanced expression of MHC-II, CD80, CD86, and phagocytosis ability of macrophages. Both OVA-loaded NPs could stimulate greater Th1-biased immune responses compared with APS alone, and they could significantly promote proliferation, differentiation, and maturity of splenic lymphocytes and dendritic cells in mice respectively. NPs induced significantly greater antigen-specific IgG antibody responses and expression of IL-4, IL-6, IFN-γ, and TNF-α. Moreover, OVA-loaded pH-responsive APSPs had an aptitude for both cellular and humoral immunity reinforcement during early immunization, while OVA-loaded APSPs had advantages on later stages of immune responses.

Structural characterization and immunoregulatory activity of a neutral polysaccharide from the roots of Apocynum venetum L.

The structural characteristics and immunoregulatory activities of neutral heteropolysaccharide (AVRP-N) separated from the roots of Apocynum venetum L. were extensively investigated. The results showed that the weight average molecular mass (Mw) of AVRP-N was 6.430 × 103 Da. Moreover, the backbone is composed of natural acetylated (1 → 4)-β-D-Man and (1 → 5)-α-L-Ara domains. The mannan is composed of →4)-β-D-Manp-(1→, →4)-β-D-Glcp-(1→, and the terminal group α-D-Galp-(1→ attached to →4,6)-β-D-Manp-(1→ at O-6. Araban is composed of →5)-α-L-Araf-(1→; the terminal group α-L-Araf-(1→attached to→2,3,5)-α-L-Araf-(1→ at O-2, O-3 and →3,5)-α-L-Araf-(1→ at O-3. In addition, the senior structure shows that AVRP-N has a triple-helix conformation. Furthermore, AVRP-N exhibited immunomodulatory effects, which could significantly regulate the proliferation of mouse splenic lymphocytes by enhancing the secretion of the cytokines (IFN-γ, IL-2, IL-4, and IL-10). Our results provide new structural and immunoregulatory information for natural polysaccharides derived from Apocynum venetum L.

The “whole ingredients extract” of Astragali Radix improves the symptoms of dextran sulfate sodium-induced ulcerative colitis in mice through systemic immunomodulation

BackgroundUlcerative colitis (UC) is a common inflammatory intestinal disease. Astragali Radix (AR) is one of the traditional Chinese medicines used in clinic for UC treatment. In our previous study, the whole ingredient extract (WIE) from AR have been proved to possess better immunomodulatory effects on immunosuppressed mice compared with the conventional water extraction (WAE). In the present study, we further evaluated the therapeutic effects of WIE against dextran sodium sulfate (DSS)-induced UC in mice through systemic immune regulation.MethodsGradient solvent extraction has been used to prepare the WIE of AR. The HPLC–MS analysis approach has been employed to analyze and compare the chemical differences between WAE and WIE. UC model was reproduced in 3% DSS-induced C57BL/6 mice for 6 days. Flow cytometric analysis for splenic lymphocyte subset. ELISA kits were used to determine the cytokines in the serum and colon tissues. The histopathological characteristics of colon were evaluated by hematoxylin–eosin staining and immunohistochemistry.ResultsThe chemical compositions and the contents of main active ingredients were more abundant and higher in WIE than those in WAE. The WIE treatment altered a better action on reducing colitis disease activity index (DAI) and histological scores, as well as the recovered body weight and increased colon length in mice compared to the WAE group. Additionally, WIE showed better effects in recovering the levels of peripheral white blood cells in blood and cytokines (IL-2, IL-6 and MCP-1) in serum or colon tissues, improving the percentage of CD3+ and the ratio of CD4+/CD8+ in the spleen, and inhibiting the spleen enlargement in DSS-induced UC mice.ConclusionsWIE has a more complete chemical composition than WAE. Meanwhile, WIE possesses better therapeutic effects on UC through resuming dysfunctional immunity in mice.

Landscape and age dynamics of immune cells in the Egyptian rousette bat.

Bats harbor high-impact zoonotic viruses often in the absence of disease manifestation. This restriction and disease tolerance possibly rely on specific immunological features. In-depth molecular characterization of cellular immunity and imprinting of age on leukocyte compartments remained unexplored in bats. We employ single-cell RNA sequencing (scRNA-seq) and establish immunostaining panels to characterize the immune cell landscape in juvenile, subadult, and adult Egyptian rousette bats (ERBs). Transcriptomic and flow cytometry data reveal conserved subsets and substantial enrichments of CD79a+ B cells and CD11b+ Tcells in juvenile animals, whereas neutrophils, CD206+ myeloid cells, and CD3+ Tcells dominate as bats reach adulthood. Despite differing frequencies, phagocytosis of circulating and tissue-resident myeloid cells and proliferation of peripheral and splenic lymphocytes are analogous in juvenile and adult ERBs. We provide a comprehensive map of the immune landscape in ERBs and show age-imprinted resilience progression and find that variability in cellular immunity only partly recapitulates mammalian archetypes.

A sesquiterpene isolated from the stems and leaves of Dioscorea opposita thunb. Transforms the composition of immune cells through ERβ in a mouse model of LPS-induced lung injury

Acute lung injury (ALI) is a common critical disease with a high mortality rate. Natural products have marked efficacy in the prevention and treatment of ALI, in addition, estrogen and its receptors are involved in the pathogenesis and development of lung injury. Our previous research shows that sesquiterpenes isolated from the stems and leaves of Dioscorea opposita Thunb. have anti-inflammatory and estrogenic-like activity. In the present study, sesquiterpene (A1) is a natural extract from the stems and leaves of Dioscorea opposita Thunb. with a view to determining whether A1 can improve lung function in a mouse model of LPS-induced ALI and exploring the involvement of the estrogen receptor β (ERβ) pathway. A1 (20 or 40 mg/kg, i. g., 2 times/day) was administered for 3 d, followed by the induction of ALI via an intratracheal LPS drip (5 mg/kg/2 h). The lung function and levels of inflammation, immune cells, apoptosis, and ERβ expression were examined. The antagonistic activity of specific ERβ blocker (THC, 1 μM) against A1 (20 μM) in co-cultured BEAS-2B cells and splenic lymphocytes induced with LPS (1 μg/mL, 24 h) was also investigated to assess whether the observed effects of A1 were mediated by ERβ. A1 improved lung function, regulated the immune system, and decreased inflammation and apoptosis. Moreover, A1 increased the expression of ERβ in LPS-induced mice, and antagonism of ERβ decreased the protective effects of A1 in a co-culture system. A1 had anti-ALI effects that might partially mediated through ERβ signaling. Our data provide molecular justification for the use of A1 in the treatment of ALI.