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Immunized Mice (immunized + mouse)
Selected AbstractsOral immunization with Porphyromonas gingivalis outer membrane protein and CpG oligodeoxynucleotides elicits T helper 1 and 2 cytokines for enhanced protective immunityMOLECULAR ORAL MICROBIOLOGY, Issue 3 2010C. Liu Summary The aim of this study was to evaluate the efficacy of an oral vaccine containing the 40-kDa outer membrane protein of Porphyromonas gingivalis (40K-OMP) and synthetic oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG ODN) to control oral infection by P. gingivalis. Oral immunization with 40K-OMP plus CpG ODN induced significant 40K-OMP-specific serum immunoglobulin G (IgG), IgA, and saliva IgA antibody responses. The 40K-OMP-specific CD4+ T cells induced by oral 40K-OMP plus CpG ODN produced both T helper type 1 (Th1; interferon-,) and Th2 (interleukin-4) cytokines. Furthermore, increased frequencies of CD11c+ B220+ dendritic cells (DCs) and CD11c+ CD11b+ DCs with upregulated expression of CD80, CD86, CD40, and major histocompatibility complex class II molecules were noted in spleen, Peyer's patches, and cervical lymph nodes. Immunized mice were then infected orally with P. gingivalis to determine whether the immune responses induced by oral 40K-OMP plus CpG ODN were capable of suppressing the bone resorption caused by P. gingivalis infection. Mice given 40K-OMP plus CpG ODN showed significantly reduced bone loss associated with oral infection by P. gingivalis. Oral administration of 40K-OMP together with CpG ODN induces Th1-type and Th2-type cells, which provide help for protective immunity against P. gingivalis infection. This may be an important tool for the prevention of chronic periodontitis. [source] T-cell tolerance induced by repeated antigen stimulation: Selective loss of Foxp3, conventional CD4 T cells and induction of CD4 T-cell anergyEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 4 2009Lena Eroukhmanoff Abstract Repeated immunization of mice with bacterial superantigens induces extensive deletion and anergy of reactive CD4 T cells. Here we report that the in vitro proliferation anergy of CD4 T cells from TCR transgenic mice immunized three times with staphylococcal enterotoxin B (SEB) (3× SEB) is partially due to an increased frequency of Foxp3+ CD4 T cells. Importantly, reduced number of conventional CD25, Foxp3, cells, rather than conversion of such cells to Foxp3+ cells, was the cause of that increase and was also seen in mice repeatedly immunized with OVA (3× OVA) and OVA,peptide (OVAp) (3× OVAp). Cell-transfer experiments revealed profound but transient anergy of CD4 T cells isolated from 3× OVAp and 3× SEB mice. However, the in vivo anergy was CD4 T-cell autonomous and independent of Foxp3+ Treg. Finally, proliferation of transferred CD4 T cells was inhibited in repeatedly immunized mice but inhibition was lost when transfer was delayed, despite the maintenance of elevated frequency of Foxp3+ cells. These data provide important implications for Foxp3+ cell-mediated tolerance in situations of repeated antigen exposure such as human persistent infections. [source] Neutrophil recruitment in immunized mice depends on MIP-2 inducing the sequential release of MIP-1,, TNF-, and LTB4EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 8 2006Cleber Abstract Neutrophils are thought to play an important role in the tissue damage observed in various autoimmune diseases. Chemokines, cytokines and leukotrienes have recognized roles in the orchestration of neutrophil migration. We have recently shown that antigen-induced neutrophil migration into the peritoneum of immunized mice is mediated by macrophage-inflammatory protein (MIP)-1, which interacts with CCR1 and induces the sequential release of TNF-, and leukotriene,B4 (LTB4). The present study investigates the role of MIP-2 and CXCR2 in the cascade of events leading to mediator generation and neutrophil influx. Antigen challenge of immunized mice induced the expression of CXCR2 and the production of KC and MIP-2 proteins. Antigen-induced neutrophil migration was inhibited by a CXCR2 receptor antagonist (repertaxin) or an anti-MIP-2 antibody, but not by an anti-KC antibody. Administration of MIP-2 promoted a dose-dependent neutrophil migration in naive mice which was inhibited by repertaxin, anti-TNF-,, anti-MIP-1, antibodies or by MK886 (leukotriene synthesis inhibitor). MIP-2 administration induced the release of MIP-1,, TNF-, and LTB4, and the release of the latter two was inhibited by anti-MIP-1, antibody treatment. Our studies highlight the intricate balance between mediator production and action during an immune-mediated inflammatory response and suggest a mediator cascade leading to neutrophil influx following antigen challenge of immunized mice: MIP-2 , MIP-1, , TNF-, , LTB4. [source] Expression of cathepsins B, D and L in mouse corneas infected with Pseudomonas aeruginosaFEBS JOURNAL, Issue 24 2001Zhong Dong C57BL/6J naïve and immunized mice were intracorneally infected with Pseudomonas aeruginosa. Semi-quantitative RT-PCR was performed to detect cathepsin gene expression and the results were further confirmed by immunoblot analysis. The enzymatic activities of cathepsins B, D and L were measured by peptidase assays. Immunohistochemical staining was carried out to localize the expression of the cathepsins. Cathepsins B, D and L were detected in the normal cornea by RT-PCR. A peptidase assay revealed activities of all three cathepsins under normal physiological conditions. In naïve mice, enzymatic activities of cathepsins B, D and L were all significantly enhanced when the corneas were infected with P. aeruginosa and the peak of the induction appeared around day 6 postinfection. Immunoblot analysis showed increased expression of cathepsins B, D and L. The infected corneal samples from immunized mice exhibited much lower induction of enzymatic activities compared to those from naïve mice. Immunohistochemistry showed that the expression of cathepsins in the normal cornea was restricted to the epithelial tissue while the induced expression of cathepsins was predominantly in the substantia propria. Our data revealed up-regulated enzymatic activities of cathepsins B, D and L in the naïve corneas infected with P. aeruginosa, which correlated well with the inflammatory response. Immunization of mice against P. aeruginosa attenuated the inducing effect on cathepsin expression caused by infection. The time sequence for induction of cathepsin proteins and enzymatic activities suggests a mechanism of host proteolytic degradation of the extracellular matrix resulting in corneal destruction after P. aeruginosa infection. [source] Mice protected by oral immunization with Lactobacillus reuteri secreting fusion protein of Escherichia coli enterotoxin subunit proteinFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2007Chi-Ming Wu Abstract A green fluorescent protein (gfp) gene was ligated to the Lactobacillus reuteri -specific nisin-inducible expression-secretion vector pNIES, generating a pNIES-GFP vector capable of secreting the cloned gene as a GFP-fusion protein with fluorescent activity. To develop this system as a live vehicle carrying the heat-stable enterotoxin (ST) and heat-labile enterotoxin B (LTB) of the enterotoxigenic Escherichia coli (ETEC), a recombinant 5,- ST - LTB -3, DNA fragment was cloned into pNIES-GFP. The resulting L. reuteri/pNIES-GFP:STLTB system was found to possess the capability of adhering to the mice gut, secreting GFP:STLTB product at 0.14 and 0.026 pgcell,1 under induced and noninduced conditions, respectively. Further analysis of the GFP:STLTB product confirmed its ganglioside-binding ability, LTB antigenicity and relative freedom from the ST-associated toxicity, making it suitable for use as an oral vaccine in mice. Oral inoculation of the L. reuteri/pNIES-GFP:STLTB culture in mice elicited significant (P<0.01) serum IgG and mucosal IgA antibodies against the STLTB antigen. These immunized mice were subsequently challenged with ETEC and showed full protection against the fluid influx response in the gut. This is the first report of using L. reuteri as a vaccine carrier to induce complete immunologic protection against ETEC. [source] Salmonella enteritidis temperature-sensitive mutants protect mice against challenge with virulent Salmonella strains of different serotypesFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2000M.Magdalena Gherardi Abstract The protection conferred by temperature-sensitive mutants of Salmonella enteritidis against different wild-type Salmonella serotypes was investigated. Oral immunization with the single temperature-sensitive mutant E/1/3 or with a temperature-sensitive thymine-requiring double mutant (E/1/3T) conferred: (i) significant protection against the homologous wild-type Salmonella strains; (ii) significant cross-protection toward high challenge doses of S. typhimurium. Significant antibody levels against homologous lipopolysaccharide and against homologous and heterologous protein antigens were detected in sera from immunized mice. Moreover, a wide range of protein antigens from different Salmonella O serotypes were recognized by sera from immunized animals. Besides, primed lymphocytes from E/1/3 immunized mice recognized Salmonella antigens from different serotypes. Taken together, these results indicate that temperature-sensitive mutants of S. enteritidis are good candidates for the construction of live vaccines against Salmonella. [source] Influence of protein conformation and adjuvant aggregation on the effectiveness of aluminum hydroxide adjuvant in a model alkaline phosphatase vaccineJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2009Amber L. Clausi Abstract The mechanism(s) of the enhancement of the immune response by addition of aluminum salt adjuvants to parenterally administered protein-based vaccines is still the subject of debate. It has been hypothesized, however, that destabilization of the antigen structure on the surface of the adjuvant may be important for eliciting immune response. Also, it has been suggested that immune response to adjuvanted vaccines is reduced if the adjuvant particles become aggregated before administration because of processing steps such as freeze-drying. In this study, we tested these hypotheses and examined the immune response in a murine model to various liquid, freeze-dried, and spray freeze-dried formulations of a model vaccine, bovine intestinal alkaline phosphatase adsorbed on aluminum hydroxide. Enzymatic activity of the alkaline phosphatase was used as a sensitive indicator of intact native antigen structure. By manipulating the secondary drying temperature during lyophilization, vaccines were produced with varying levels of alkaline phosphatase enzymatic activity and varying degrees of adjuvant aggregation, as assessed by particle size distribution. Anti-alkaline phosphatase titers observed in immunized mice were independent of both the antigen's retained enzymatic activity and the vaccine formulation's mean particle diameter. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:114,121, 2009 [source] Chloroplast-derived vaccine antigens confer dual immunity against cholera and malaria by oral or injectable deliveryPLANT BIOTECHNOLOGY JOURNAL, Issue 2 2010Abdoreza Davoodi-Semiromi Summary Cholera and malaria are major diseases causing high mortality. The only licensed cholera vaccine is expensive; immunity is lost in children within 3 years and adults are not fully protected. No vaccine is yet available for malaria. Therefore, in this study, the cholera toxin-B subunit (CTB) of Vibrio cholerae fused to malarial vaccine antigens apical membrane antigen-1 (AMA1) and merozoite surface protein-1 (MSP1) was expressed in lettuce and tobacco chloroplasts. Southern blot analysis confirmed homoplasmy and stable integration of transgenes. CTB-AMA1 and CTB-MSP1 fusion proteins accumulated up to 13.17% and 10.11% (total soluble protein, TSP) in tobacco and up to 7.3% and 6.1% (TSP) in lettuce, respectively. Nine groups of mice (n = 10/group) were immunized subcutaneously (SQV) or orally (ORV) with purified antigens or transplastomic tobacco leaves. Significant levels of antigen-specific antibody titres of immunized mice completely inhibited proliferation of the malarial parasite and cross-reacted with the native parasite proteins in immunoblots and immunofluorescence studies. Protection against cholera toxin challenge in both ORV (100%) and SQV (89%) mice correlated with CTB-specific titres of intestinal, serum IgA and IgG1 in ORV and only IgG1 in SQV mice, but no other immunoglobulin. Increasing numbers of interleukin-10+ T cell but not Foxp3+ regulatory T cells, suppression of interferon-, and absence of interleukin-17 were observed in protected mice, suggesting that immunity is conferred via the Tr1/Th2 immune response. Dual immunity against two major infectious diseases provided by chloroplast-derived vaccine antigens for long-term (>300 days, 50% of mouse life span) offers a realistic platform for low cost vaccines and insight into mucosal and systemic immunity. [source] FK506 as an adjuvant of tolerogenic DNA vaccination for the prevention of experimental autoimmune encephalomyelitisTHE JOURNAL OF GENE MEDICINE, Issue 11 2009Youmin Kang Abstract Background DNA vaccination is a strategy that has been developed primarily to elicit protective immunity against infection and cancer. Methods DNA vaccine was used, in conjunction with an immunosuppressant, to tolerize harmful autoimmunity. Results Immunization of C57BL/6 mice with MOG35,55, a myelin oligodendrocyte glycoprotein-derived peptide, and FK506 (Tacrolimus) as a tolerogenic adjuvant stimulated regulatory dendritic cells, induced antigen-specific regulatory T cells (Treg), and protected the animals from subsequent induction of experimental autoimmune encephalomyelitis (EAE). After EAE induction, there were fewer lymphocytes, including fewer T helper 17 cells, and more Treg infiltrating the spinal cord in the immunized mice compared to in control mice. Furthermore, at the peak of the EAE manifestation, CD4 T cells in the immunized mice showed decreased expression of interferon-, and interleukin (IL)-17, but not IL-4, in treated mice. Conclusions DNA vaccination, when applied with an immunosuppressant as adjuvant, can induce antigen-specific tolerance and prevent autoimmune disease. Copyright © 2009 John Wiley & Sons, Ltd. [source] Vaccinations With Dendritic Cells Primed With Apoptotic Tumor Cells Can Elicit Preventive Antitumor Immunity in a Poorly Immunogenic Animal Model of Squamous Cell CarcinomaTHE LARYNGOSCOPE, Issue 9 2007Han-Sin Jeong MD Abstract Background: Dendritic cells (DCs) can effectively mediate the prevention and regression of a variety of solid tumors. However, not much has been determined about their efficacy for the prevention of squamous cell carcinoma (SCC), partly because there are no known tumor-specific antigens or low immunogenicity for this tumor. The authors aimed to determine the preventive effect of DC-based immunotherapy in a SCC animal model. Methods: Bone marrow derived DCs of C3H/He mice were pulsed with ultraviolet,B-irradiated apoptotic SCCVII cells, which are known as a poorly immunogenic SCC cell line. After the animals were vaccinated with these DCs, a tumorigenic dosage of SCCVII cells was subcutaneously injected and the tumor growth assessed. Results: Animals pretreated with apoptotic SCCVII cell-pulsed DCs showed tumor extinction within 2 weeks after forming a small tumor, or there was no tumor formation at all, as seen in 81% of the mice; in the remaining 19% of the mice, tumor growth was significantly retarded compared with the control groups (P = .0029). The SCCVII cell-specific T-cell response was observed in the immunized mice. Conclusion: The adoptive transfer of DCs primed with apoptotic tumor cells can hopefully serve as an effective preventive vaccine, even in poorly immunogenic SCC. [source] Tissue targeting of anti-RNP autoimmunity: Effects of T cells and myeloid dendritic cells in a murine modelARTHRITIS & RHEUMATISM, Issue 2 2009Eric L. Greidinger Objective To explore the role of immune cells in anti-RNP autoimmunity in a murine model of pneumonitis or glomerulonephritis, using adoptive transfer techniques. Methods Donor mice were immunized with 50 ,g of U1,70-kd small nuclear RNP fusion protein and 50 ,g of U1 RNA adjuvant. Whole splenocytes as well as CD4+ cell and dendritic cell (DC) subsets from the immunized mice were infused into naive syngeneic recipients. Anti-RNP and T cell responses were assessed by immunoblotting, enzyme-linked immunosorbent assay, and flow cytometry. Development of renal or lung disease was assessed by histology and urinalysis. Results Unfractionated splenocytes from donor mice without proteinuria induced predominantly lung disease in recipients (8 [57%] of 14 versus 2 [14%] of 14 developing renal disease; P = 0.046). However, infusion of CD4+ cells from donors without proteinuria induced renal disease more frequently than lung disease (7 [70%] of 10 versus 2 [20%] of 10; P = 0.01); adoptive transfer of RNP+CD4+ T cells from short-term culture yielded similar results (renal disease in 8 [73%] of 11 recipients versus lung disease in 3 [27%] of 11). Cotransfer of splenic myeloid DCs and CD4+ T cells from immunized donors prevented induction of renal disease in all 5 recipients (P = 0.026 versus recipients of fresh CD4+ cells alone), although lung disease was still observed in 1 of 5 mice. Transfer of myeloid DCs alone from immunized donors induced lung disease in 3 (60%) of 5 recipients, without evidence of nephritis. Cotransfer of splenocytes from mice with and those without nephritis led to renal disease in 4 of 5 recipients, without evidence of lung disease. Conclusion These findings indicate that RNP+CD4+ T cells are sufficient to induce anti-RNP autoimmunity, tissue targeting in anti-RNP autoimmunity can be deviated to either a renal or pulmonary phenotype depending on the presence of accessory cells such as myeloid DCs, and DC subsets can play a role in both propagation of autoimmunity and end-organ targeting. [source] A murine model of mixed connective tissue disease induced with U1 small nuclear RNP autoantigenARTHRITIS & RHEUMATISM, Issue 2 2006Eric L. Greidinger Objective To test whether immunizing mice with autoantigens closely linked to mixed connective tissue disease (MCTD) could induce an MCTD-like clinical syndrome distinguishable from systemic lupus erythematosus (SLE). Methods Transgenic and knockout C57BL/6-derived mice were immunized subcutaneously at age 8,12 weeks with U1,70-kd small nuclear RNP (70K) fusion protein along with either Freund's complete adjuvant (CFA) or U1 RNA. After 2 months, mice were killed and analyzed histologically and serologically. Results Immunization of C57BL/6-derived mice transgenic for human HLA,DR4 with 70K and either CFA or U1 RNA led to anti-70K antibodies in 62% of mice (21 of 34), and diversified anti-RNP immune responses. MCTD-like lung disease also developed in 50% of immunized mice (17 of 34), and anti-70K antibodies were strongly correlated with lung disease. CFA and U1 RNA were comparably able to induce this syndrome. Mice deficient in Toll-like receptor 3 (TLR-3) also developed this same syndrome when immunized with 70K and CFA. However, TLR-3,/, mice failed to develop MCTD-like lung disease when treated with 70K and U1 RNA. Rather, TLR-3,/, mice immunized with 70K and U1 RNA developed an autoimmune syndrome characterized by glomerulonephritis typical of SLE. Conclusion Exposure to 70K in an appropriate context is sufficient to induce autoimmunity and target organ injury consistent with MCTD. This system represents a new model of autoimmune interstitial lung disease, and establishes a closer link between anti-70K immunity and MCTD-like lung disease. Of note, changes in innate immune signaling can cause the same trigger to lead to the development of SLE-like nephritis rather than MCTD-like lung disease. [source] Antigen dose-dependent suppression of murine IgE responses is mediated by CD4,CD8, double-negative T cellsCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2010C. Barwig Summary Background The IgE response against protein antigens is profoundly influenced by the dose used for sensitization. Objective The aim of the study was to identify immune cells that are involved in antigen dose-dependent regulation of IgE formation. Methods Wild-type mice as well as T helper (Th)1-deficient IL-12p40,/, and IFN-,,/, mice were immunized by repeated intraperitoneal injection of either low doses (K01 mice) or high doses (K100 mice) of keyhole limpet haemocyanin adsorbed to aluminium hydroxide. Splenocytes of immunized mice were restimulated in vitro and antigen-dependent T cell proliferation and cytokine production were measured. The frequency of regulatory T cell subsets among splenocytes from K01 and K100 mice was compared using fluorocytometry and RT-PCR analysis. Splenocytes or T cell subpopulations were transferred into naïve mice and the effect of lymphocyte transfer on IgE production after priming of recipients with low antigen doses was determined. Results Specific IgE production was considerably impaired in K100 mice. Antigenic restimulation revealed hypoproliferation of K100 splenocytes and reduced production of Th2 cytokines IL-4, IL-5 and IL-13, but no induction of IFN-, production. Moreover, lymphocytes from K01 and K100 mice did not show significant differences in the expression of molecules associated with the phenotype or activity of conventional regulatory T cells. Transfer of splenocytes or purified T cells from K100 mice substantially suppressed the induction of IgE production in the recipients in an antigen- and isotype-specific manner. Neither CD4+ nor CD8+ T cells from K100 mice were able to inhibit IgE formation; instead, we identified CD4,CD8, double-negative T cells (dnT cells) as the principal T cell population, which potently suppressed IgE production. Conclusion Our data demonstrate that CD4,CD8, dnT cells play a major role in the regulation of IgE responses induced by high antigen doses. [source] Cyclosporin A inhibits eosinophilic infiltration into the conjunctiva mediated by type IV allergic reactionsCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2006Atsuki Fukushima MD Abstract Background:, Eosinophils are important effector cells in severe allergic conjunctivitis such as vernal keratoconjunctivitis. Infiltration of eosinophils into the conjunctiva is mediated by type I and type IV allergic reactions. Cyclosporin A (CsA) eye drops are administered therapeutically for severe allergic conjunctivitis, but the mechanism by which CsA acts, that is, by inhibiting type I, type IV or both types of allergic reactions, is not known. We investigated whether CsA eye drops inhibit type I, type IV or both types of allergic reactions in the conjunctiva. Methods:, Experimental immune-mediated blepharoconjunctivitis (EC) was induced in BALB/c mice by either active immunization or passive immunization by transfer of ragweed (RW)-primed splenocytes and RW-specific IgE, followed by RW challenge to the conjunctiva. These mice were treated in eye drops with vehicle, 0.1% CsA, 0.5% CsA or 0.1% betamethasone five times (1 and 2 h before RW challenge and 1, 2 and 3 h after RW challenge). Twenty-four hours after the challenge, the conjunctivas were harvested for histological analysis to evaluate eosinophilic infiltration. To evaluate effects of CsA eye drops on systemic immune responses, sera and spleens were collected from actively immunized mice at the time of sacrifice to examine serum IgE levels and cellular immune responses, respectively. Results:, CsA eye drops significantly inhibited eosinophilic infiltration into the conjunctiva in actively immunized EC-developing mice compared with vehicle-treated mice. The CsA-induced inhibition was similar to inhibition induced by 0.1% betamethasone. Serum IgE levels and splenocyte responses in CsA-treated mice were equivalent to those in vehicle-treated mice. Betamethasone treatment inhibited eosinophilic infiltration into the conjunctiva induced by both splenocyte transfer and IgE transfer, while CsA treatment inhibited infiltration induced by splenocyte transfer. Conclusions:, CsA eye drops inhibited eosinophilic infiltration into the conjunctiva without affecting systemic immune responses. CsA predominantly inhibits eosinophilic infiltration by interfering with the type IV allergic reaction in the conjunctiva. [source] | ||||||||||||||||