Inhibitory/suppressive oligodeoxynucleotide nanocapsules as simple oral delivery devices for preventing atopic dermatitis in mice

Explore Alteration of Lung and Gut Microbiota in a Murine Model of OVA-Induced Asthma Treated by CpG Oligodeoxynucleotides

Aim

We sought to investigate the impact of CpG oligodeoxynucleotides (CpG-ODN) administration on the lung and gut microbiota in asthmatic mice, specifically focusing on changes in composition, diversity, and abundance, and to elucidate the microbial mechanisms underlying the therapeutic effects of CpG-ODN and identify potential beneficial bacteria indicative of its efficacy.

Methods

HE staining were used to analyze inflammation in lung, colon and small intestine tissues. High-throughput sequencing technology targeting 16S rRNA was employed to analyze the composition, diversity, and correlation of microbiome in the lung, colon and small intestine of control, model and CpG-ODN administration groups.

Results

(1) Histopathologically, both lung and intestinal tissue in asthmatic mice exhibited significant structural damage and inflammatory response, whereas the structure of both lung and intestinal tissue approached normal levels, accompanied by a notable improvement in the inflammatory response after CpG-ODN treatment. (2) In the specific microbiota composition analysis, bacterial dysbiosis observed in the asthmatic mice, accompanied by enrichment of Proteobacteria found to cause lung and intestinal epithelial damage and inflammatory reaction. After CpG-ODN administration, bacterial dysbiosis was improved, and a notable enrichment of beneficial bacteria, indicating a novel microecology. Meanwhile Oscillospira and Clostridium were identified as two biomarkers of the CpG-ODN treatment. (3) Heatmap analysis revealed significant correlations among lung, small intestine, and colon microbiota.

Conclusion

CpG-ODN treatment can ameliorate OVA-induced asthma in mice. One side, preserving the structural integrity of the lung and intestine, safeguarding the mucosal physical barrier, the other side, improving the dysbiosis of lung and gut microbiota in asthmatic mice. Beneficial bacteria and metabolites take up microecological advantages, regulate immune cells and participate in the mucosal immune response to protect the immune barrier. Meanwhile, Oscillospira and Clostridium as biomarkers for CpG-ODN treatment, has reference significance for exploring precise Fecal microbiota transplantation treatment for asthma.

Challenges of current treatment and exploring the future prospects of nanoformulations for treatment of atopic dermatitis

Atopic dermatitis (AD) is a predominant and deteriorating chronic inflammation of the skin, categorized by a burning sensation and eczematous lesions in diverse portions of the body. The treatment of AD is exclusively focused to limit the itching, reduce inflammation, and repair the breached barrier of the skin. Several therapeutic agents for the treatment and management of AD have been reported and are in use in clinics. However, the topical treatment of AD has been an unswerving challenge for the medical fraternity owing to the impaired skin barrier function in this chronic skin condition. To surmount the problems of conventional drug delivery systems, numerous nanotechnology-based formulations are emerging as alternative new modalities for AD. Latter enhances the bioavailability and delivery to the target disease site, improves drug permeation and therapeutic efficacy with reduced systemic and off-target side effects, and thus improves patient health and promotes compliance. This review aims to describe the various pathophysiological events involved in the occurrence of AD, current challenges in treatment, evidence of molecular markers of AD and its management, combinatorial treatment options, and the intervention of nanotechnology-based formulations for AD therapeutics.

Peyer's patch phagocytes acquire specific transcriptional programs that influence their maturation and activation profiles

Peyer's patches (PPs) are secondary lymphoid organs in contact with the external environment via the intestinal lumen, thus combining antigen sampling and immune response initiation sites. Therefore, they provide a unique opportunity to study the entire process of phagocyte differentiation and activation in vivo. Here, we deciphered the transcriptional and spatial landscape of PP phagocyte populations from their emergence in the tissue to their final maturation state at homeostasis and under stimulation. Activation of monocyte-derived Lysozyme-expressing dendritic cells (LysoDCs) differs from that of macrophages by their upregulation of conventional DC (cDC) signature genes such as Ccr7 and downregulation of typical monocyte-derived cell genes such as Cx3cr1. We identified gene sets that distinguish PP cDCs from the villus ones and from LysoDCs. We also identified key immature, early, intermediate, and late maturation markers of PP phagocytes. Finally, exploiting the ability of the PP interfollicular region to host both villous and subepithelial dome emigrated cDCs, we showed that the type of stimulus, the subset, but also the initial location of cDCs shape their activation profile and thus direct the immune response. Our study highlights the importance of targeting the right phagocyte subset at the right place and time to manipulate the immune response.

Free Feeding of CpG-Oligodeoxynucleotide Particles Prophylactically Attenuates Allergic Airway Inflammation and Hyperresponsiveness in Mice

CpG-oligodeoxynucleotides (CpG-ODNs) constitute an attractive alternative for asthma treatment. However, very little evidence is available from studies on the oral administration of CpG-ODNs in animals. Previously, we developed acid-resistant particles (named ODNcap) as an oral delivery device for ODNs. Here, we showed that free feeding of an ODNcap-containing feed prophylactically attenuates allergic airway inflammation, hyperresponsiveness, and goblet cell hyperplasia in an ovalbumin-induced asthma model. Using transcriptomics-driven approaches, we demonstrated that injury of pulmonary vein cardiomyocytes accompanies allergen inhalation challenge, but is inhibited by ODNcap feeding. We also showed the participation of an airway antimicrobial peptide (Reg3γ) and fecal microbiota in the ODNcap-mediated effects. Collectively, our findings suggest that daily oral ingestion of ODNcap may provide preventive effects on allergic bronchopulmonary insults via regulation of mechanisms involved in the gut-lung connection.

Myogenetic oligodeoxynucleotide complexed with berberine promotes differentiation of chicken myoblasts

Myoblasts are myogenic precursors that develop into myotubes during muscle formation. Improving efficiency of myoblast differentiation is important for advancing meat production by domestic animals. We recently identified novel oligodeoxynucleotides (ODNs) termed myogenetic ODNs (myoDNs) that promote the differentiation of mammalian myoblasts. An isoquinoline alkaloid, berberine, forms a complex with one of the myoDNs, iSN04, and enhances its activities. This study investigated the effects of myoDNs on chicken myoblasts to elucidate their species-specific actions. Seven myoDNs (iSN01-iSN07) were found to facilitate the differentiation of chicken myoblasts into myosin heavy chain (MHC)-positive myotubes. The iSN04-berberine complex exhibited a higher myogenetic activity than iSN04 alone, which was shown to enhance the differentiation of myoblasts into myotubes and the upregulation of myogenic gene expression (MyoD, myogenin, MHC, and myomaker). These data indicate that myoDNs promoting chicken myoblast differentiation may be used as potential feed additives in broiler diets.

CpG Oligonucleotides as Vaccine Adjuvants

CpG Oligonucleotides (ODN) are immunomodulatory synthetic oligonucleotides specifically designed to stimulate Toll-like receptor 9. TLR9 is expressed on human plasmacytoid dendritic cells and B cells and triggers an innate immune response characterized by the production of Th1 and pro-inflammatory cytokines. This chapter reviews recent progress in understanding the mechanism of action of CpG ODN and provides an overview of human clinical trial results using CpG ODN to improve vaccines for the prevention/treatment of cancer, allergy, and infectious disease.

Identification of the Myogenetic Oligodeoxynucleotides (myoDNs) That Promote Differentiation of Skeletal Muscle Myoblasts by Targeting Nucleolin

Herein we report that the 18-base telomeric oligodeoxynucleotides (ODNs) designed from the Lactobacillus rhamnosus GG genome promote differentiation of skeletal muscle myoblasts which are myogenic precursor cells. We termed these myogenetic ODNs (myoDNs). The activity of one of the myoDNs, iSN04, was independent of Toll-like receptors, but dependent on its conformational state. Molecular simulation and iSN04 mutants revealed stacking of the 13-15th guanines as a core structure for iSN04. The alkaloid berberine bound to the guanine stack and enhanced iSN04 activity, probably by stabilizing and optimizing iSN04 conformation. We further identified nucleolin as an iSN04-binding protein. Results showed that iSN04 antagonizes nucleolin, increases the levels of p53 protein translationally suppressed by nucleolin, and eventually induces myotube formation by modulating the expression of genes involved in myogenic differentiation and cell cycle arrest. This study shows that bacterial-derived myoDNs serve as aptamers and are potential nucleic acid drugs directly targeting myoblasts.

Oral priming with oligodeoxynucleotide particles from Lactobacillus rhamnosus GG attenuates symptoms of dextran sodium sulfate-induced acute colitis in mice

Here, we investigated the effect of prophylactic oral treatment with carbonate apatite-based particles (ID35caps) containing Lactobacillus rhamnosus GG-derived immunostimulatory oligodeoxynucleotides (ID35) when used in mice with acute colitis. Mice were administered orally with control particles (carbonate apatite particles, Caps), ID35, or ID35caps for 2 days, and then were given free access to drinking water containing 3% (w/v) dextran sodium sulfate (DSS) for 5 days (Days 0-5) to induce acute colitis. Body weight change, fecal bleeding, and stool consistency were monitored and scored as a disease activity index (DAI) to assess symptoms of colitis. On Day 10, animals were euthanized and the colon length was measured to evaluate inflammatory tissue injury. Prophylactic oral treatment with ID35caps significantly suppressed DSS-induced elevation of the DAI score and shortening of the colon compared to the respective parameters in DSS-exposed mice treated with Cap or ID35. We conclude that oral priming with ID35caps attenuates symptoms and inflammatory colonic injury in a mouse model of DSS-induced acute colitis. This finding suggests that ID35caps may be a new oral agent for preventing intestinal inflammation.

Microbial therapeutics for acute colitis based on genetically modified Lactococcus lactis hypersecreting IL-1Ra in mice

The increased incidence of inflammatory bowel disease (IBD) in Western and rapidly Westernizing developing countries poses a global pandemic threat. The development of affordable drugs for treating IBD worldwide is thus a priority. Genetically modified lactic acid bacteria (gmLAB) as microbial therapeutics are inexpensive protein producers suitable for use as carriers of protein to the intestinal mucosa. Here, we successfully constructed gmLAB hypersecreting interleukin 1 receptor antagonist (IL-1Ra). Oral administration of these gmLAB suppressed body weight reduction and exacerbation of the disease activity index score in mice with acute colitis and decreased the number of CD4⁺ IL-17A⁺ cells in the mesenteric lymph nodes. These data suggest that the gmLAB deliver IL-1Ra to the colon, where it inhibits IL-1 signaling. We thus developed a novel IBD therapeutic that blocks IL-1 signaling using a gmLAB protein delivery system. This system could be an inexpensive oral microbial therapeutic.

Genetically reprogrammed bacteria can facilitate the efficient delivery of a therapeutic protein for treating inflammatory bowel disease (IBD). Interleukin 1 receptor antagonist (IL-1Ra) inhibits the immune cells that attack the intestinal lining in IBD patients, but current administration strategies are associated with serious side effects. Takeshi Shimosato and colleagues at Shinshu University in Nagano, Japan, have engineered the microbe Lactococcus lactis to secrete high levels of IL-1Ra. The researchers dosed mice orally with these bacteria, which released IL-1Ra into the intestinal tissue. This treatment proved safe and effectively reduced inflammation and associated symptoms in a mouse model of ulcerative colitis. L. lactis has previously been tested as a probiotic in clinical trials, and may therefore offer an appealing alternative to subcutaneous administration of IBD drugs in human patients.

Nanotechnology meets atopic dermatitis: Current solutions, challenges and future prospects. Insights and implications from a systematic review of the literature

Atopic dermatitis is a chronic, relapsing, non-contiguous, exudative eczema/dermatitis, which represents a complex, multi-factorial disorder, due to an impairment of the stratum corneum barrier. Currently available drugs have a low skin bioavailability and may give rise to severe adverse events. Nanotechnologies, including nano-particles, liposomes, nano-gels, nano-mixtures, nano-emulsions and other nano-carriers, offer unprecedented solutions to these issues, enabling: i) the management of different clinical forms of atopic dermatitis, especially the recalcitrant ones, i) a better bio-availability and trans-dermal drug targeted delivery at the inflammation site, ii) dose control, iii) significant improvements both in clinical symptoms and immune responses, iv) with less adverse events being reported and a better safety profile. However, some nano-sized structures could amplify and even worsen symptoms in particularly susceptible individuals. Furthermore, most studies included in the present systematic review have been conducted in-vitro or in-vivo, with few randomized controlled clinical trials (RCTs). Future investigations should adopt this design in order to enable scholars achieving robust findings and evidence. Therefore, given the above-mentioned shortcomings, further research in the field is urgently warranted.

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Atopic dermatitis is a chronic, relapsing eczema/dermatitis, due to an impairment of the stratum corneum barrier.

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Currently available drugs have a low skin bioavailability and may give rise to severe adverse events.

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Nanotechnologies offer unprecedented solutions, enabling the management of different clinical forms of atopic dermatitis.

Cooperation of Oligodeoxynucleotides and Synthetic Molecules as Enhanced Immune Modulators

Unmethylated cytosine–guanine dinucleotide (CpG) motifs are potent stimulators of the host immune response. Cellular recognition of CpG motifs occurs via Toll-like receptor 9 (TLR9), which normally activates immune responses to pathogen-associated molecular patterns (PAMPs) indicative of infection. Oligodeoxynucleotides (ODNs) containing unmethylated CpGs mimic the immunostimulatory activity of viral/microbial DNA. Synthetic ODNs harboring CpG motifs resembling those identified in viral/microbial DNA trigger an identical response, such that these immunomodulatory ODNs have therapeutic potential. CpG DNA has been investigated as an agent for the management of malignancy, asthma, allergy, and contagious diseases, and as an adjuvant in immunotherapy. In this review, we discuss the potential synergy between synthetic ODNs and other synthetic molecules and their immunomodulatory effects. We also summarize the different synthetic molecules that function as immune modulators and outline the phenomenon of TLR-mediated immune responses. We previously reported a novel synthetic ODN that acts synergistically with other synthetic molecules (including CpG ODNs, the synthetic triacylated lipopeptide Pam₃CSK₄, lipopolysaccharide, and zymosan) that could serve as an immune therapy. Additionally, several clinical trials have evaluated the use of CpG ODNs with other immune factors such as granulocyte-macrophage colony-stimulating factor, cytokines, and both endosomal and cell-surface TLR ligands as adjuvants for the augmentation of vaccine activity. Furthermore, we discuss the structural recognition of ODNs by TLRs and the mechanism of functional modulation of TLRs in the context of the potential application of ODNs as wide-spectrum therapeutic agents.

Adjuvanted Immunotherapy Approaches for Peanut Allergy

Food allergies are a growing public health concern with an estimated 8% of US children affected. Peanut allergies are also on the rise and often do not spontaneously resolve, leaving individuals at-risk for potentially life-threatening anaphylaxis throughout their lifetime. Currently, two forms of peanut immunotherapy, oral immunotherapy (OIT) and epicutaneous immunotherapy (EPIT), are in Phase III clinical trials and have shown promise to induce desensitization in many subjects. However, there are several limitations with OIT and EPIT, such as allergic side effects, daily dosing requirements, and the infrequent outcome of long-term tolerance. Next-generation therapies for peanut allergy should aim to overcome these limitations, which may be achievable with adjuvanted immunotherapy. An adjuvant can be defined as anything that enhances, accelerates, or modifies an immune response to a particular antigen. Adjuvants may allow for lower doses of antigen to be given leading to decreased side effects; may only need to be administered every few weeks or months rather than daily exposures; and may induce a long-lasting protective effect. In this review article, we highlight examples of adjuvants and formulations that have shown pre-clinical efficacy in treating peanut allergy.

Immune synergistic oligodeoxynucleotide from Lactobacillus rhamnosus GG enhances the immune response upon co-stimulation by bacterial and fungal cell wall components

Bacterial genomic DNA has recently been shown to elicit a highly evolved immune defense. This response can be selectively triggered for a wide range of therapeutic applications, including use as a vaccine adjuvant to immunotherapies for allergy, cancer, and infectious diseases. Previously, we identified a low-concentration immune synergistic oligodeoxynucleotide (iSN-ODN, named iSN34) from Lactobacillus rhamnosus GG that has immunosynergistic activity upon costimulation of target cells with ligands of Toll-like receptor 9 (TLR9). Here, we extend that observation by demonstrating the synergistic induction (in mouse splenocytes) of IL-6 by the combination of iSN34 with cell wall components of bacteria and fungi. We observed that splenocytes pretreated with iSN34 and then costimulated with agonists for TLR1/2 (Pam₃ CSK₄ ), TLR4 (lipopolysaccharide), or TLR2/6 (Zymosan) exhibited enhanced accumulation of IL-6. These results suggested that the combination of iSN34 with TLR1/2, TLR4, or TLR2/6 agonists may permit the induction of a potent immune response.

Synergistic oligodeoxynucleotide strongly promotes CpG-induced interleukin-6 production

Background

Bacterial genomes span a significant portion of diversity, reflecting their adaptation strategies; these strategies include nucleotide usage biases that affect chromosome configuration. Here, we explore an immuno-synergistic oligodeoxynucleotide (iSN-ODN, named iSN34), derived from Lactobacillus rhamnosus GG (LGG) genomic sequences, that exhibits a synergistic effect on immune response to CpG-induced immune activation.

Methods

The sequence of iSN34 was designed based on the genomic sequences of LGG. Pathogen-free mice were purchased from Japan SLC and maintained under temperature- and light-controlled conditions. We tested the effects of iSN34 exposure in vitro and in vivo by assessing effects on mRNA expression, protein levels, and cell type in murine splenocytes.

Results

We demonstrate that iSN34 has a significant stimulatory effect when administered in combination with CpG ODN, yielding enhanced interleukin (IL)-6 expression and production. IL-6 is a pleotropic cytokine that has been shown to prevent epithelial apoptosis during prolonged inflammation.

Conclusions

Our results are the first report of a bacterial-DNA-derived ODN that exhibits immune synergistic activity. The potent over-expression of IL-6 in response to treatment with the combination of CpG ODN and iSN34 suggests a new approach to immune therapy. This finding may lead to novel clinical strategies for the prevention or treatment of dysfunctions of the innate and adaptive immune systems.

Electronic supplementary material

The online version of this article (10.1186/s12865-017-0227-7) contains supplementary material, which is available to authorized users.

Class A CpG Oligonucleotide Priming Rescues Mice from Septic Shock via Activation of Platelet-Activating Factor Acetylhydrolase

Sepsis is a life-threatening, overwhelming immune response to infection with high morbidity and mortality. Inflammatory response and blood clotting are caused by sepsis, which induces serious organ damage and death from shock. As a mechanism of pathogenesis, platelet-activating factor (PAF) induces excessive inflammatory responses and blood clotting. In this study, we demonstrate that a Class A CpG oligodeoxynucleotide (CpG-A₁₅₈₅) strongly induced PAF acetylhydrolase, which generates lyso-PAF. CpG-A₁₅₈₅ rescued mice from acute lethal shock and decreased fibrin deposition, a hallmark of PAF-induced disseminated intravascular coagulation. Furthermore, CpG-A₁₅₈₅ improved endotoxin shock induced by lipopolysaccharide, which comprises the cell wall of Gram-negative bacteria and inhibits inflammatory responses induced by cytokines such as interleukin-6 and tumor necrosis factor-α. These results suggest that CpG-A₁₅₈₅ is a potential therapeutic target to prevent sepsis-related induction of PAF.

Effect of Calcium Carbonate Encapsulation on the Activity of Orally Administered CpG Oligonucleotides

Synthetic oligodeoxynucleotides containing unmethylated CpG motifs (CpG ODNs) stimulate immune cells via Toll-like receptor 9 (TLR9). Because oligodeoxynucleotides (ODNs) are susceptible to gastric degradation, clinical trials designed to evaluate their therapeutic utility have relied solely on parenteral routes of administration. A strategy to improve the activity of orally delivered ODNs by reducing their susceptibility to gastrointestinal (GI) digestion via encapsulation in calcium carbonate nanoparticles (ODNcaps) was recently described. This study compares the in vitro and in vivo activity of encapsulated (ODNcaps) versus free CpG ODNs delivered orally or parenterally. ODNcaps mirrored the ability of free ODNs to stimulate splenic B cells and macrophages in vitro. ODNcaps activated immune cells in the Peyer’s patches and mesenteric lymph nodes after oral delivery. Their effect on GI immunity was evaluated in studies of dextran sulfate sodium (DSS)-induced colitis and enteric infection, whereas systemic immunity was examined by monitoring their effect on lipopolysaccharide (LPS)-induced cytokine production and systemic pathogen challenge. Results indicate that orally delivered CpG ODNs predominantly induce GI rather than systemic immunity, and that calcium carbonate encapsulation does not significantly alter this behavior.

Preventive Effect of Lactobacillus helveticus SBT2171 on Collagen-Induced Arthritis in Mice

We recently reported that the intraperitoneal inoculation of Lactobacillus helveticus SBT2171 inhibited the development of collagen-induced arthritis (CIA), a murine model of rheumatoid arthritis (RA). In the present study, we evaluated the effect of the oral administration of L. helveticus SBT2171 on CIA development and on the regulation of antigen-specific antibody production and inflammatory immune cells, which have been implicated in the development of RA. Both oral administration and intraperitoneal inoculation of L. helveticus SBT2171 reduced joint swelling, body weight loss, and the serum level of bovine type II collagen (CII)-specific antibodies in the CIA mouse model. The intraperitoneal inoculation also decreased the arthritis incidence, joint damage, and serum level of interleukin (IL)-6. In addition, the numbers of total immune cells, total B cells, germinal center B cells, and CD4⁺ T cells in the draining lymph nodes were decreased following intraperitoneal inoculation of L. helveticus SBT2171. These findings demonstrate the ability of L. helveticus SBT2171 to downregulate the abundance of immune cells and the subsequent production of CII-specific antibodies and IL-6, thereby suppressing the CIA symptoms, indicating its potential for use in the prevention of RA.

Coenzyme Q10 Suppresses TNF-α-Induced Inflammatory Reaction In Vitro and Attenuates Severity of Dermatitis in Mice

Anti-oxidant coenzyme Q10 (Co-Q10) is commonly used in clinic. Recently, Co-Q10 was reported to antagonize TNF-α-induced inflammation and play a protective role in various inflammatory conditions. However, its role in dermatitis is unknown. Herein, RAW264.7 macrophage cell line was cultured with stimulation of TNF-α, and administration of Co-Q10 alleviated TNF-α-mediated inflammatory reaction in vitro. Furthermore, oxazolone-induced dermatitis mice model was established, and treatment of Co-Q10 markedly attenuated dermatitis phenotype in this mice model. Moreover, the protective role of Co-Q10 in vitro and in dermatitis was probably due to its repression on NF-κB signaling. Collectively, Co-Q10 may represent a potential molecular target for prevention and treatment of inflammatory skin diseases.

Structure, mechanism and therapeutic utility of immunosuppressive oligonucleotides

Synthetic oligodeoxynucleotides that can down-regulate cellular elements of the immune system have been developed and are being widely studied in preclinical models. These agents vary in sequence, mechanism of action, and cellular target(s) but share the ability to suppress a plethora of inflammatory responses. This work reviews the types of immunosuppressive oligodeoxynucleotide (Sup ODN) and compares their therapeutic activity against diseases characterized by pathologic levels of immune stimulation ranging from autoimmunity to septic shock to cancer (see graphical abstract). The mechanism(s) underlying the efficacy of Sup ODN and the influence size, sequence and nucleotide backbone on function are considered.

Use of nanoparticles to deliver immunomodulatory oligonucleotides

Synthetic oligonucleotides (ODNs) containing unmethylated 'CpG motifs' stimulate the innate immune system to produce cytokines, chemokines, and polyreactive antibodies. CpG ODNs have shown promise as vaccine adjuvants and for the treatment of infectious diseases and cancer. The immunostimulatory activity of CpG ODNs is inhibited by DNA-containing 'suppressive' motifs. ODNs expressing suppressive motifs (Sup ODNs) reduce ongoing immune reactions and show promise in the treatment of autoimmune and inflammatory diseases. This work reviews recent progress in the use of nanoparticles as carriers of CpG and Sup ODNs to target their delivery to the GI tract and lungs. WIREs Nanomed Nanobiotechnol 2016, 8:631-637. doi: 10.1002/wnan.1382 For further resources related to this article, please visit the WIREs website.

Oral delivery of Lactococcus lactis that secretes bioactive heme oxygenase-1 alleviates development of acute colitis in mice

BACKGROUND

Mucosal delivery of therapeutic proteins using genetically modified strains of lactic acid bacteria (gmLAB) is being investigated as a new therapeutic strategy.

METHODS

We developed a strain of gmLAB, Lactococcus lactis NZ9000 (NZ-HO), which secretes the anti-inflammatory molecule recombinant mouse heme oxygenase-1 (rmHO-1). The effects of short-term continuous oral dosing with NZ-HO were evaluated in mice with dextran sulfate sodium (DSS)-induced acute colitis as a model of inflammatory bowel diseases (IBD).

RESULTS

We identified the secretion of rmHO-1 by NZ-HO. rmHO-1 was biologically active as determined with spectroscopy. Viable NZ-HO was directly delivered to the colon via oral administration, and rmHO-1 was secreted onto the colonic mucosa in mice. Acute colitis in mice was induced by free drinking of 3 % DSS in water and was accompanied by an increase in the disease activity index score and histopathological changes. Daily oral administration of NZ-HO significantly improved these colitis-associated symptoms. In addition, NZ-HO significantly increased production of the anti-inflammatory cytokine interleukin (IL)-10 and decreased the expression of pro-inflammatory cytokines such as IL-1α and IL-6 in the colon compared to a vector control strain.

CONCLUSIONS

Oral administration of NZ-HO alleviates DSS-induced acute colitis in mice. Our results suggest that NZ-HO may be a useful mucosal therapeutic agent for treating IBD.

Development of a simple IgE-independent anaphylactic model using buckwheat antigen and B-type CpG oligodeoxynucleotide from Streptococcus thermophilus

We developed a severe anaphylactic model in mice using buckwheat antigen and B-type CpG-oligodeoxynucleotides (CpG-ODNs) from Streptococcus thermophilus genome. In typical systemic anaphylaxis models, animals are challenged with large quantity of antigens via an intravenous (i.v.) route. Here, we showed a simple anaphylactic shock after challenge via intraperitoneal (i.p.) route. The i.p. method is simpler than i.v. administration and has a lower risk for failure. To generate this anaphylactic model, 5-week-old female BALB/c mice were first i.p. sensitized with buckwheat antigen mixed with B-type CpG-ODN. After 2 weeks, mice were challenged with antigen to induce anaphylactic shock, which was evaluated by scoring the severity symptoms and measuring serum levels of various proteins and splenic cell producing cytokines. Immunoglobulin (Ig)G2a production and interferon-γ positive cells were markedly increased in mice immunized with antigen mixed with B-type CpG-ODN, whereas serum IgE levels were decreased by B-type CpG-ODN. We also examined the effects of various ODNs (A, B and C-type CpG-ODNs) and antigens (buckwheat, α-casein, β-lactoglobulin and ovalbumin) on anaphylactic severity, and found that the combination of buckwheat and B-type CpG-ODN induced the most intense anaphylactic shock. This model is expected to contribute to the study of the prevention of anaphylactic shock.