Rosuvastatin attenuates airway inflammation and remodeling in a chronic allergic asthma model through modulation of the AMPKα signaling pathway.

The efficacy of rosuvastatin in reducing allergic inflammation has been established. However, its potential to reduce airway remodeling has yet to be explored. This study aimed to evaluate the efficacy of rosuvastatin in reducing airway inflammation and remodeling in a mouse model of chronic allergic asthma induced by sensitization and challenge with OVA. Histology of the lung tissue and the number of inflammatory cells in bronchoalveolar lavage fluid (BALF) showed a marked decrease in airway inflammation and remodeling in mice treated with rosuvastatin, as evidenced by a decrease in goblet cell hyperplasia, collagen deposition, and smooth muscle hypertrophy. Furthermore, levels of inflammatory cytokines, angiogenesis-related factors, and OVA-specific IgE in BALF, plasma, and serum were all reduced upon treatment with rosuvastatin. Western blotting was employed to detect AMPK expression, while immunohistochemistry staining was used to observe the expression of remodeling signaling proteins such as α-SMA, TGF-ß, MMP-9, and p-AMPKα in the lungs. It was found that the activity of 5'-adenosine monophosphate-activated protein kinase alpha (AMPKα) was significantly lower in the lungs of OVA-induced asthmatic mice compared to Control mice. However, the administration of rosuvastatin increased the ratio of phosphorylated AMPK to total AMPKα, thus inhibiting the formation of new blood vessels, as indicated by CD31-positive staining mainly in the sub-epithelial region. These results indicate that rosuvastatin can effectively reduce airway inflammation and remodeling in mice with chronic allergic asthma caused by OVA, likely due to the reactivation of AMPKα and a decrease in angiogenesis.

Toxicarioside H-mediated modulation of the immune microenvironment attenuates ovalbumin-induced allergic airway inflammation by inhibiting NETosis.

PURPOSE: Our team identified a new cardiac glycoside, Toxicarioside H (ToxH), in a tropical plant. Previous research has indicated the potential of cardenolides in mitigating inflammation, particularly in the context of NETosis. Therefore, this study sought to examine the potential of ToxH in attenuating allergic airway inflammation by influencing the immune microenvironment. METHODS: An OVA-induced airway inflammation model was established in BALB/c mice. After the experiment was completed, serum, bronchoalveolar lavage fluid (BALF), and lung tissue samples were collected and further examined using H&E and PAS staining, flow cytometry, immunofluorescence observation, and Western blot analysis. RESULTS: Treatment with ToxH was found to be effective in reducing airway inflammation and mucus production. This was accompanied by an increase in Th1 cytokines (IFN-γ, IL-2, and TNF-ß), and the Th17 cytokine IL-17, while levels of Th2 cytokines (IL-4, IL-5, and IL-13) and Treg cytokines (IL-10 and TGF-ß1) were decreased in both the bronchoalveolar lavage fluid (BALF) and the CD45+ immune cells in the lungs. Additionally, ToxH inhibited the infiltration of inflammatory cells and decreased the number of pulmonary CD44+ memory T cells, while augmenting the numbers of Th17 and Treg cells. Furthermore, the neutrophil elastase inhibitor GW311616A was observed to suppress airway inflammation and mucus production, as well as alter the secretion of immune Th1, Th2, Th17, and Treg cytokines in the lung CD45+ immune cells. Moreover, our study also demonstrated that treatment with ToxH efficiently inhibited ROS generation, thereby rectifying the dysregulation of immune cells in the immune microenvironment in OVA-induced allergic asthma. CONCLUSIONS: Our findings indicate that ToxH could serve as a promising therapeutic intervention for allergic airway inflammation and various other inflammatory disorders. Modulating the balance of Th1/Th2 and Treg/Th17 cells within the pulmonary immune microenvironment may offer an effective strategy for controlling allergic airway inflammation.

Penicilazaphilone C alleviates allergic airway inflammation and improves the immune microenvironment by hindering the NLRP3 inflammasome.

AIMS: Penicilazaphilone C (PAC) is hypothesized to potentially serve as a therapeutic treatment for allergic airway inflammation by inhibiting the NLRP3 inflammasome and reducing oxidative stress. METHODS: An allergic asthma model was induced in female BALB/c mice of the OVA, OVA+PAC, OVA+PAC+LPS, and OVA+Dex groups by sensitizing and subsequently challenging them with OVA. The OVA+PAC and Normal+PAC groups were treated with PAC, while the OVA+PAC+LPS group also received LPS. The OVA+Dex group was given dexamethasone (Dex). Samples of serum, bronchoalveolar lavage fluid (BALF), and lung tissue were collected for histological and cytological analysis. RESULTS: Allergic mice treated with PAC or Dex showed inhibited inflammation and mucus production in the lungs. There was a decrease in the number of inflammatory cells in the BALF, lower levels of inflammatory cytokines in the serum and BALF, and a reduction in the protein expression of NLRP3, ASC, cleaved caspase-1, IL-1ß, activated gasdermin D, MPO, Ly6G, and ICAM-1. Additionally, oxidative stress was reduced, as shown by a decrease in MDA and DCF, but an increase in SOD and GSH. Treatment with PAC also resulted in a decrease in pulmonary memory CD4+ T cells and an increase in regulatory T cells. However, the positive effects seen in the PAC-treated mice were reversed when the NLRP3 inflammasome was activated by LPS, almost returning to the levels of the Sham-treated mice. SIGNIFICANCE: PAC acts in a similar way to anti-allergic inflammation as Dex, suggesting it may be a viable therapeutic option for managing allergic asthma inflammation.

Sestrin2 mediates FOXM1 expression to block the EMT process in non-small cell lung cancer through the AMPK/YAP pathway.

Non-small cell lung cancer (NSCLC) is characterized by high incidence and mortality, severely threatening human health. The infinite growth and metastasis of NSCLC cells result in a poor prognosis. Therefore, our study was to investigate the mechanism of Sestrin2 on the epithelial-mesenchymal transition (EMT) process of NSCLC cells. Human embryonic lung fibroblasts, NSCLC cell lines, and nude mice were experimental subjects in this study. qRT-PCR and western blot were performed to evaluate the mRNA and protein expression of genes. CCK-8 and EdU assay were conducted to detect cell proliferation. The scratch test and Transwell assay were applied to examine cell migration and invasion. The bioinformatics analysis and Co-IP assay were employed to predict and consolidate the interaction between YAP and TEAD. We found the expression of Sestrin2 was declined but the expression of YAP was elevated in NSCLC cells. Sestrin2 sufficiency or YAP silencing could effectively impair cell growth and metastasis. Mechanistically, YAP interacted with TEAD to enhance FOXM1 expression. Additionally, the elevation of FOXM1 abolished the inhibitory influences of Sestrin2 sufficiency on NSCLC cell growth, invasion, and EMT process. Eventually, Sestrin2 elevation attenuated tumor growth in mice via modulation of the AMPK/YAP/FOXM1 axis, which was reversed by FOXM1 overexpression. Our consequences suggested Sestrin2 could inhibit the activation of YAP via prompting AMPK phosphorylation and then suppress FOXM1 expression through the interplay between YAP and TEAD to impair the capacities of NSCLC cell proliferation, migration, invasion, and EMT. This study provided a novel mechanism of Sestrin2 in NSCLC.

Immunotherapy combining tumor and endothelium cell lysis with immune enforcement by recombinant MIP-3α Newcastle disease virus in a vessel-targeting liposome enhances antitumor immunity.

BACKGROUND: Several agents for oncolytic immunotherapy have been approved for clinical use, but monotherapy is modest for most oncolytic agents. The combination of several therapeutic strategies through recombinant and nanotechnology to engineer multifunctional oncolytic viruses for oncolytic immunotherapy is a promising strategy. METHODS: An endothelium-targeting iRGD-liposome encapsulating a recombinant Newcastle disease virus (NDV), which expresses the dendritic cell (DC) chemokine MIP-3α (iNDV3α-LP), and three control liposomes were constructed. MIP-3α, HMGB1, IgG, and ATP were detected by western blotting or ELISA. The chemotaxis of DCs was examined by Transwell chambers. The phenotypes of the immune cells were analyzed by flow cytometry. The antitumor efficiency was investigated in B16 and 4T1 tumor-bearing mice. Immunofluorescence and immunohistochemistry were used to observe the localization of liposomes, molecular expression and angiogenesis. Synergistic index was calculated using the data of tumor volume, tumor angiogenesis and tumor-infiltrating lymphocytes. RESULTS: Compared with NDV-LP, treatment with iNDV3α-LP and NDV3α-LP induced stronger virus replication and cell lysis in B16 and 4T1 tumor cells and human umbilical vein endothelial cells (HUVECs) with the best response observed following iNDV3α-LP treatment. B16 and 4T1 cells treated with iNDV3α-LP produced more damage-associated molecular pattern molecules, including secreted HMGB1, ATP, and calreticulin. Moreover, iNDV3α-LP specifically bound to αvß3-expressing 4T1 cells and HUVECs and to tumor neovasculature. Tumor growth was significantly suppressed, and survival was longer in iNDV3α-LP-treated B16-bearing and 4T1-bearing mice. A mechanism study showed that iNDV3α-LP treatment initiated the strongest tumor-specific cellular and humoral immune response. Moreover, iNDV3α-LP treatment could significantly suppress tumor angiogenesis and reverse the tumor immune suppressive microenvironment in both B16-bearing and 4T1-bearing mice. CONCLUSIONS: In this study, iNDV3α-LP had several functions, such as tumor and vessel lysis, MIP-3α immunotherapy, and binding to αvß3-expressing tumor and its neovasculature. iNDV3α-LP treatment significantly suppressed tumor angiogenesis and reversed the tumor immunosuppressive microenvironment. These findings offer a strong rationale for further clinical investigation into a combination strategy for oncolytic immunotherapy, such as the formulation iNDV3α-LP in this study.

Engineered porous/hollow Burkholderia pseudomallei loading tumor lysate as a vaccine.

Due to its size, shape, and inherent expression of pathogen-associated molecular patterns and invasion-assistant adhesion proteins, Burkholderia pseudomallei can easily attach to, and then be internalized by, dendritic cells (DCs), leading to more efficient antigen cross-presentation if modified as carrier. Herein, we engineered Burkholderia pseudomallei as a porous/hollow carrier (SB) for loading tumor lysates (L) and adjuvant CpG (C) to be used as a tumor vaccine (SB-LC). We found that the adhesion proteins of Burkholderia pseudomallei promote internalization of the SB-LC vaccine by DCs, and result in enhanced DC maturation and antigen cross-presentation. SB-LC induces robust cellular and humoral antitumor responses that synergistically inhibit tumor growth with minimal adverse side effects in several tumor models. Moreover, SB-LC vaccination reverses the immunosuppressive tumor microenvironment, apparently as a result of CD8+-induced tumor ferroptosis. Thus, SB-LC is a potential model tumor vaccine for translating into a clinically viable treatment option.

Exopolysaccharide from Paecilomyces lilacinus modulates macrophage activities through the TLR4/NF­κB/MAPK pathway.

Multiple exopolysaccharides (EPSs) have been isolated from various organisms in extreme environments and have yielded a variety of activities. The present study evaluated the immunomodulatory capabilities of an EPS (termed PH­EPS) derived from the fungus Paecilomyces lilacinus PH0016, which was isolated from a tropical and hyperhaline environment in southern China. The macrophage RAW 264.7 cell line was used to investigate the mechanism of PH­EPS­induced macrophage activation. The results indicated that RAW 264.7 macrophages were activated by PH­EPS, in an effect slightly inferior to lipopolysaccharide (LPS), as evidenced by secretion of interleukin (IL)­1ß, tumor necrosis factor (TNF)­α and nitric oxide (NO), and by significantly increased phagocytosis in the cells treated with PH­EPS. Nuclear factor (NF)­κB p65 was significantly translocated into the nucleus in the PH­EPS­treated cells. In addition, expression of inducible NO synthase (iNOS) and IκB­α degradation were enhanced in PH­EPS­treated cells. The phosphorylation levels of p38, JNK and ERK were also significantly increased in the PH­EPS­treated cells. Furthermore, IL­1ß and TNF­α production was markedly decreased in PH­EPS­treated cells when the mitogen­activated protein kinase (MAPK) pathways were blocked by the inhibitor Dectin­1 and by antibodies against Toll­like receptor 4 (TLR4). The present results indicated that PH­EPS from Paecilomyces lilacinus possessed the capability of activating RAW 264.7 cells via the TLR4/NF­κB/MAPKs signaling pathway.

Induction of enhanced immunogenic cell death through ultrasound-controlled release of doxorubicin by liposome-microbubble complexes.

Immunogenic cell death (ICD) is a specific kind of cell death that stimulates the immune system to combat cancer cells. Ultrasound (US)-controlled targeted release of drugs by liposome-microbubble complexes is a promising approach due to its non-invasive nature and visibility through ultrasound imaging. However, it is not known whether this approach can enhance ICD induced by drugs, such as doxorubicin. Herein, we prepared a doxorubicin-liposome-microbubble complex (MbDox), and the resultant MbDox was then characterized and tested for US-controlled release of Dox (MbDox+US treatment) to enhance the induction of ICD in LL/2 and CT26 cancer cells and in syngeneic murine models. We found that MbDox+US treatment caused more cellular uptake and nuclear accumulation of Dox in tumor cells, and more accumulation of Dox in tumor tissues. Enhanced induction of ICD occurred both in vitro and in vivo. MbDox+US treatment induced more apoptosis, stronger membrane exposure and the release of ER stress proteins and DAMPs in tumor cells, and increased DC maturation in vitro. In addition, MbDox+US treatment also resulted in stronger therapeutic effects in immunocompetent mice than in immunodeficient mice. Moreover, MbDox+US enhancement of ICD was also evidenced by a higher proportion of activated CD8+ T-lymphocytes but lower Treg in tumor tissues. Taken together, our results demonstrate that US-controlled release of ICD inducers into nuclei using liposome-microbubble complexes may be an effective approach to enhance the induction of ICD for tumor treatment.

3'-epi-12ß-hydroxyfroside, a new cardenolide, induces cytoprotective autophagy via blocking the Hsp90/Akt/mTOR axis in lung cancer cells.

Rationale: Cardenolides have potential as anticancer drugs. 3'-epi-12ß-hydroxyfroside (HyFS) is a new cardenolide structure isolated by our research group, but its molecular mechanisms remain poorly understood. This study investigates the relationship between its antitumor activities and autophagy in lung cancer cells. Methods: Cell growth and proliferation were detected by MTT, lactate dehydrogenase (LDH) release, 5-ethynyl-20-deoxyuridine (EDU) and colony formation assays. Cell apoptosis was detected by flow cytometry. Autophagic and signal proteins were detected by Western blotting. Markers of autophagy and autophagy flux were also detected by immunofluorescence, transmission electron microscopy and acridine orange staining. Real time RT-PCR was used to analyze the gene expression of Hsp90. Hsp90 ubiquitination was detected by coimmunoprecipitation. The antitumore activities of HyFS were observed in nude mice. Results: HyFS treatment inhibited cell proliferation and induced autophagy in A549 and H460 lung cancer cells, but stronger inhibition of cell proliferation and induction of cell apoptosis were shown when HyFS-mediated autophagy was blocked. The Hsp90/Akt/mTOR axis was found to be involved in the activation of HyFS-mediated autophagy. Evidence of direct interaction between Hsp90 and Akt was observed. HyFS treatment resulted in decreased levels of heat shock protein 90 (Hsp90) and phosphorylated Akt, overexpression of Hsp90 increased activation of autophagy, and inhibition of Hsp90 expression decreased autophagy. In addition, ubiquitin-mediated degradation of Hsp90 and subsequent dephosphorylation of its client protein Akt were also found in HyFS-treated lung cancer cells. Moreover, combination treatment with HyFS and chloroquine showed remarkably increased tumor inhibition in both A549- and H460-bearing mice. Conclusion: Our results demonstrate that HyFS induced cytoprotective autophagy through ubiquitin-mediated degradation of Hsp90, which further blocked the Akt/mTOR pathway in lung cancer cells. Thus, a combination of a HyFS-like cardenolide and an autophagic inhibitor is a potential alternative approach for the treatment of lung cancer.

Coroglaucigenin induces senescence and autophagy in colorectal cancer cells.

OBJECTIVES: Coroglaucigenin (CGN), a natural product isolated from Calotropis gigantean by our research group, has been identified as a potential anti-cancer agent. However, the molecular mechanisms involved remain poorly understood. MATERIALS AND METHODS: Cell viability and cell proliferation were detected by MTT and BrdU assays. Flow cytometry, SA-ß-gal assay, western blotting and immunofluorescence were performed to determine CGN-induced apoptosis, senescence and autophagy. Western blotting, siRNA transfection and coimmunoprecipitation were carried out to investigate the mechanisms of CGN-induced senescence and autophagy. The anti-tumour activities of combination therapy with CGN and chloroquine were observed in mice tumour models. RESULTS: We demonstrated that CGN inhibits the proliferation of colorectal cancer cells both in vitro and in vivo. We showed that the inhibition of cell proliferation by CGN is independent of apoptosis, but is associated with cell-cycle arrest and senescence in colorectal cancer cells. Notably, CGN induces protective autophagy that attenuates CGN-mediated cell proliferation. Functional studies revealed that CGN disrupts the association of Hsp90 with both CDK4 and Akt, leading to CDK4 degradation and Akt dephosphorylation, eventually resulting in senescence and autophagy, respectively. Combination therapy with CGN and chloroquine resulted in enhanced anti-tumour effects in vivo. CONCLUSIONS: Our results demonstrate that CGN induces senescence and autophagy in colorectal cancer cells and indicate that combining it with an autophagy inhibitor may be a novel strategy suitable for CGN-mediated anti-cancer therapy.

Toxicarioside O induces protective autophagy in a sirtuin-1-dependent manner in colorectal cancer cells.

Colorectal cancer is the most common cancer. It has high morbidity and mortality worldwide, and more effective treatment strategies need to be developed. Toxicarioside O (TCO), a natural product derived from Antiaris toxicaria, has been shown to be a potential anticancer agent. However, the molecular mechanisms involved remain poorly understood. In this study, our results demonstrated that TCO can induce both apoptosis and autophagy in colorectal cancer cells. Moreover, TCO-induced autophagy was due to the increase of the expression and activity of the enzyme sirtuin-1 (SIRT1), and subsequent inhibition of the Akt/mTOR pathway. Inhibition of SIRT1 activity by its inhibitor, EX-527, attenuated TCO-induced autophagy. Of interest, inhibition of autophagy by chloroguine, an autophagy inhibitor, enhanced TCO-induced apoptotic cell death, suggesting that autophagy plays a protective role in TCO-induced apoptosis. Together, these findings suggest that combination of TCO and autophagy inhibitor may be a novel strategy suitable for potentiating the anticancer activity of TCO for treatment of colorectal cancer.

ADAM33 gene polymorphisms identified to be associated with asthma in a Chinese Li population.

A disintegrin and metalloprotease 33 (ADAM33) is an asthma susceptibility gene that has been proven to be present in certain human populations. The Li population is a minority ethnic group, most of whom maintain a distinctive lifestyle on Hainan Island in southern China. To the best of our knowledge, no previous study has established whether ADAM33 polymorphisms are associated with asthma in the Li population. Therefore, the ADAM33 polymorphisms in a Li population were investigated in the present study. A total of 150 asthma patients and 100 healthy subjects were enrolled in the present study, and their DNA samples were evaluated to analyze eight single-nucleotide polymorphisms (SNPs) on the ADAM33 gene. Asthma patients were subcategorized into low and high severity groups, and their SNP data were compared with the data of the control subjects. Single-marker and haplotype association was analyzed to demonstrate the association between ADAM33 SNPs and asthma using multiple genetic statistic tests. The results indicated significant differences in allele frequencies at the SNPs rs44707/T2 (P=0.008), rs2787094/V4 (P=0.028) and rs2280089/T+1 (P=0.021) between asthma patients and control subjects. The SNP rs44707/T2 was also found to be associated with the high severity group (P=0.024), although SNPs rs2787094/V4 were associated with the low severity group (P=0.019). Two haplotypes, GGAGAGT and GAAGGGT, were significantly associated with asthma (P=0.003 and 0.008, respectively). To the best of our knowledge, this is the first time that SNP rs2280089/T+1 has been reported to be associated with asthma in an Asian population. These data confirm that ADAM33 polymorphisms are associated with asthma susceptibility in the Li population and confirm the uniqueness of the Li minority population within China.

Strophalloside induces apoptosis of SGC-7901 cells through the mitochondrion-dependent caspase-3 pathway.

Cardenolides with special chemical structures have been considered as effective anti-cancer drugs in clinic trials. Strophalloside is a cardenolide we recently isolated from Antiaris toxicaria obtained from Hainan, China. The aim of this study was to investigate the possible anticancer effects induced by strophalloside and the underlying molecular mechanism. Gastric carcinoma SGC-7901 cells were treated with strophalloside at various concentrations for different times, and resulting cell viability was determined by the MTT assay, and the motility and invasion of tumor cells were assessed by the Transwell chamber assay. Apoptosis were measured by Annexin V-FITC/PI and Hoechst staining. The changes of mitochondrial transmembrane potential were examined by a JC-1 kit. The expressions of pro-apoptotic protein cytochrome c, caspase-3 and caspase-9 were detected by western blotting analysis. The results showed that strophalloside was capable of reducing cell viability, inhibiting cell growth, and suppressing cell migration and invasion in a time- and dose-dependent manner. Mitochondrial membrane potential declined and the concentration of cytochrome c increased in cytoplasm and caspase-3 and caspase-9 were cleaved into activated states, suggesting that cytochrome c was released from the mitochondrion to cytoplasm and finally activated the caspase-dependent apoptosis pathway. Our results indicate that strophalloside is a potential anticancer drug.

Antigen 43/Fcε3 chimeric protein expressed by a novel bacterial surface expression system as an effective asthma vaccine.

The IgE Fcε3 domain is an active immunotherapeutic target for asthma and other allergic diseases. However, previous methods for preparing IgE fusion protein vaccines are complex. Antigen 43 (Ag43) is a surface protein found in Escherichia coli that contains α and ß subunits (the α subunit contains multiple T epitopes). Here we constructed a novel Ag43 surface display system (Ag43 system) to express Ag43 chimeric proteins to disrupt immune tolerance against IgE. The Ag43 system was constructed from the E. coli strain Tan109, in which the Ag43 gene was deleted and a recombinant plasmid (pETAg43) expressing a partial Ag43 gene was introduced. The Fcε3 domain of the IgE gene was then subcloned into plasmid pETAg43, resulting in a recombinant plasmid pETAg43/Fcε3, which was used to transform Tan109 for Ag43/Fcε3 surface expression. Thereafter, Ag43/Fcε3 was investigated as an asthma vaccine in a mouse model. Ag43/Fcε3 was expressed on and could be separated from the bacterial surface by heating to 60° while retaining activity. Ag43/Fcε3, as a protein vaccine, produced neutralizing autoantibodies to murine IgE, induced significant anti-asthma effects, and regulated IgE and T helper cytokines in a murine asthma model. Data show that Ag43/Fcε3 chimeric protein is a potential model vaccine for asthma treatment, and that the Ag43 system may be an effective tool for novel vaccine preparation to break immune tolerance to other self-molecules.

Antisense interleukin-5 reduces eosinophil infiltration and hyperresponsiveness in an allergic asthma model.

Interleukin-5 (IL-5) involves in the development of airway inflammation and hyperresponsiveness through activation of eosinophils. Thus, inhibition of IL-5 expression seems to be an attractive approach for asthma therapy. In this study, an antisense IL-5 gene transferred by recombinant adeno-associated virus (asIL-5) was constructed to transfect murine allergic asthma model. Our results showed that asIL-5 efficiently inhibited the IL-5 mRNA expression and significantly attenuated the inflammation in lung tissues. Significant decreasing of eosinophils and inflammatory cells were found in peripheral blood and bronchoalveolar lavage fluid (BALF). In addition, significant inhibition of airway hyperresponsiveness (AHR) was also found in the mice treated with asIL-5. These observations demonstrate that antisense oligonucleotid against IL-5 delivered by adeno-associated virus system is possibly an efficacious therapeutic strategy for allergic asthma and other eosinophil-related disorders.

RNA interference against interleukin-5 attenuates airway inflammation and hyperresponsiveness in an asthma model.

Interleukin-5 (IL-5) accompanies the development of airway inflammation and hyperresponsiveness through the activation of eosinophils. Therefore, interference of IL-5 expression in lung tissue seems to be an accepted approach in asthma therapy. In this study, we designed a small interfering RNA (siRNA) to inhibit the expression of IL-5. The siRNAs against IL-5 were constructed in a lentivirus expressing system, and 1.5x10(6) IFU (inclusion-forming unit) lentiviruses were administered intratracheally to ovalbumin (OVA)-sensitized murine asthmatic models. Our results show that lentivirus-delivered siRNA against IL-5 efficiently inhibited the IL-5 messenger ribonucleic acid (mRNA) expression and significantly attenuated the inflammation in lung tissue. Significant decrease of eosinophils and inflammatory cells were found in peripheral blood, bronchoalveolar lavage fluid (BALF), and lung tissue. In addition, significant inhibition of airway hyperresponsiveness (AHR) was found in the mice treated with siRNA against IL-5. These observations demonstrate that siRNA delivered by means of the lentivirus system is possibly an efficacious therapeutic approach for asthma.

A recombinant DNA plasmid encoding the human interleukin-5 breaks immunological tolerance and inhibits airway inflammation in a murine model of asthma.

BACKGROUND: Eosinophils play a pivotal role in the generation of asthma inflammation. Interleukin (IL)-5 is the major activator of eosinophils. We hypothesize that modulating IL-5 activity could be an effective strategy for asthma therapy. In this study, we tested whether the plasmid encoding human IL-5 as a xenogeneic DNA vaccine could induce the production of autoantibodies, and be used for asthma treatment. METHODS: A eukaryotic plasmid encoding the human IL-5 was constructed, and used as a DNA vaccine. A mouse model of asthma was established to observe its antiasthma activities. Eosinophils in tissue, blood and the bronchoalveolar lavage were stained and counted. Airway hyperresponsiveness (AHR) was determined by whole body plethysmography. Antibody characters and cytokines were detected with immunological methods. RESULTS: Immunization with a plasmid encoding the human IL-5 as DNA vaccine reduced airway inflammation, reversed Th2 cytokines, and decreased AHR in mice. In addition, this immunization induced the production of polyclonal antibodies that were cross-reactive with native murine IL-5, and IgG1 and IgG2a were the major subclasses. Adoptive transfer of the purified antibodies from the sera of mice immunized with the plasmid encoding the human IL-5 resulted in similar antiasthma effects. CONCLUSIONS: Our results suggest that active vaccination against IL-5 may be a rational therapeutic approach for the treatment of asthma and potentially other eosinophilic disorders.

Active immunotherapy of allergic asthma with a recombinant human interleukin-5 protein as vaccine in a murine model.

BACKGROUND: Eosinophils are highly related to allergic asthma inflammation. Interleukin (IL)-5 is the major chemokine of eosinophils, inhibition of the activity of IL-5 thus seems to be a potential approach to asthma therapy. The current study was performed to determine whether a recombinant human IL-5 protein as a xenogeneic vaccine has the capability of inducing anti-asthma activities. METHODS: Recombinant human IL-5 was used as a protein vaccine. Mouse asthma model was established to observe the anti-asthma activities. Lung histology was observed; eosinophils in blood and bronchoalveolar lavage were stained and counted. Airway hyperresponsiveness was determined by whole body plethysmograph. Antibody characters and cytokines were detected with enzyme linked immunosorbent assay (ELISA) and Western blot assay. RESULTS: Vaccination with recombinant human IL-5 protein as vaccine significantly reduced airway inflammation and airway hyperresponsiveness, and shifted the cytokine production from Th2 (IL-4) to Th1 (INF-gamma) in mice allergic-asthma model. Immunization with recombinant human IL-5 protein vaccine bypassed the immunological tolerance and induced production of polyclonal antibodies that were cross-reactive with murine IL-5. CONCLUSIONS: Active immunization with xenogeneic homologous IL-5 may be a possible therapeutic approach to the treatment of asthma and potentially of other eosinophilic disorders.