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1.
Bahman Tabaraie Bal Krishan Sharma Praveen Rishi nee Sharma Rakesh Sehgal Nirmal Kumar Ganguly 《Microbiology and immunology》1994,38(7):561-565
Porins were prepared from smooth strain of Salmonella typhi 0–901 and chemotype rough mutant of S. typhimurium Ra-30. Porins could significantly stimulate the immune systems of mice. Immunization of mice with the porins provoked synthesis of anti-porin antibodies. Macrophages from the immunized mice showed increased capacity to generate oxygen free radicals, and lymphocytes from these mice showed proliferative response to the porins. Thus porins may play a role in providing protection from salmonellosis by stimulating the antibody production and increasing the capacity of macrophages to generate oxygen free radicals along with stimulation of lymphocytes. 相似文献
2.
Bahman Tabaraie Bal Krishan Sharma Praveen Rishi nee Sharma Rakesh Sehgal Nirmal Kumar Ganguly 《Microbiology and immunology》1994,38(7):553-559
Porins were prepared from smooth strain of Salmonella typhi 0–901 and chemotype of rough mutant of S. typhimurium Ra-30. Mice were immunized with both the porin preparations in different groups and challenged with S. typhimurium LT2–71 and S. enteritidis SH-1269. Porin immunized mice showed significant protection (P <0.01) against challenge with homologous as well as heterologous strains. Hence, the use of porins may be attempted in future to protect against salmonellosis. 相似文献
3.
Protective efficacy and immunogenicity of Vi-porin conjugate against Salmonella typhi. 总被引:1,自引:0,他引:1
A conjugate vaccine against Salmonella typhi was prepared by covalently binding capsular polysaccharide (Vi) with porin, both isolated from S. typhi. First, Vi and porins were extracted. The Vi was purified from S. typhi Ty2. The purified Vi conformed to the requirements of the World Health Organization. Porins were purified from S. typhi 0901. The Vi was bound to the porins by a heterobifunctional cross-linking reagent, N-succinimidyl-3-(2-pyridyl dithio)-propionate (SPDP). After preparing the Vi-porin conjugate, its protective ability and immunogenicity were studied in mice following systemic immunization. The results showed that the conjugate is 6.5-fold more protective than Vi alone against S. typhi. The mice immunized with conjugate elicited higher anti-Vi antibody (IgG) levels (P < 0.01) than the mice immunized with Vi alone. Anti-porin antibodies were also induced by the conjugate. To study the mucosal immune responses, secretory IgA (sIgA) in the intestinal fluid was measured. Conjugate-immunized mice showed the induction of sIgA as compared to Vi alone. The results showed that when Vi is bound to porins, both isolated from same organism, the resultant conjugate induced both systemic and mucosal immune responses and provided better protection against S. typhi than Vi alone. 相似文献
4.
Luz P. Blanco Cecilia S. Toro Jaime M. Romero Carlos A. Santiviago Guido C. Mora 《Microbiology and immunology》1997,41(12):999-1003
The immunogenic effect of Salmonella typhi OmpC porin during typhoid fever in humans was evaluated in vitro. Peripheral blood mononuclear cells from 17 patients were challenged with outer membrane preparations from Escherichia coli UH302 and UH302/pSTP2K2 strains, both lacking E. coli OmpF and OmpC porins, although UH302/pSTP2K2 expressed a plasmid-encoded S. typhi Ty2 OmpC. The mononuclear cell supernatants, immunized in vitro with OmpC antigen, derived from 10 out of 17 patients activated U937 bactericidal capacity. In contrast, the supernatants from the immunization with outer membrane preparation lacking S. typhi Ty2 OmpC induced a significantly reduced bactericidal capacity of U937 cells. This procedure should prove useful for in vitro characterization of cellular immunogens from exclusive human pathogens. 相似文献
5.
Carlos Maurício De Andrade Antnio Gomes Pinto Ferreira Joana D'Arc Cardoso Da Silva Hilton Jorge Nascimento Jos Godinho Da Silva Junior 《Microbiology and immunology》1998,42(8):521-526
A new immunogenic outer membrane protein, Omp-28 (MW 28,000 and pI 4.6), was isolated from smooth Salmonella typhi cells by the use of an extracting medium containing 6 m urea, 1% deoxycholate and 5 mM EDTA. The purification of Omp-28 was performed by gel filtration and fast ion exchange chromatography. This protein showed to be the prevalent component isolated by the latter methodology. Omp-28 is formed by three identical subunits (MW 9,000), not linked by disulfide bonds. The partial N-terminal amino acid sequence of Omp-28 presented great homology with part of the sequence of an Escherichia coli protein found in a precursor whose sequence was predicted by c-DNA. ELISA and Western blotting identified Omp-28 as the major antigenic protein present in the outer membrane protein fraction, isolated by gel filtration. Antibodies against Omp-28 were detected by ELISA in 43% of 28 sera from typhoid fever convalescent patients. The antisera from mice immunized with Omp-28 and the highest positive typhoid fever convalescent serum gave a positive bactericidal test, killing 50% of Salmonella typhi cells in serum dilutions of 1/80 and 1/320, respectively. These results indicate the immunogenic importance of Omp-28 isolated from Salmonella typhi outer membrane and strongly suggest it should be used in further studies of animal protection against the disease caused by this pathogenic bacteria. 相似文献
6.
Fumiko Nishikawa Eiji Kita Norio Matsui Shuzo Kashiba 《Microbiology and immunology》1994,38(3):201-207
The effector cells responsible for protection to Salmonella typhimurium in C3H/HeJ mice, conferred by L-form S. typhimurium, were determined by cell transfer test. Nonfractionated spleen cells from 6-week immune mice but not from 24-week immune animals transferred anti-S. typhimurium immunity. Treatment with anti-macrophage antiserum and complement most effectively abolished protective capacity in 6-week immune cells, while anti-T cell monoclonal antibody plus complement reduced it to a lesser extent. However, adoptive protection was achieved only by transfer of immune macrophages along with Lyt-2+ T cells selected from 6-week immune spleen cells. These Lyt-2+ T cells were cytotoxic to Kupffer cells from C3H/HeJ mice which had been infected 48 hr previously and from the mice which had been immunized 1 week previously, but not to the cells from 6-week immune mice and from normal animals. Moreover, protective capacity in immune macrophages seemed to be correlated to the degree of colonization by the L forms, and the inability to transfer immunity of 24-week immune spleen cells may be due to the decrease in the L form-colonization. These results suggest that cooperation between the L form-colonized macrophages and L form-induced cytotoxic Lyt-2+ T cells contributes to anti-S. typhimurium immunity, and might imply the immunological difference between the 6-week immune phagocytes and the cells at an early stage of infection or immunization. 相似文献
7.
丙型肝炎病毒(HCV)核心蛋白是丙肝疫苗的重要候选抗原,然而,该蛋白因具有免疫调控作用而影响免疫应答的诱导。构建了HCV核心蛋白的两种表达质粒,一种是体内激活型原核表达质粒pZW-C,另一种是真核表达质粒pCI-C。将该两种质粒转化减毒鼠伤寒沙门菌SL7207,得到重组菌SL7207/pZW-C和SL7207/pCI-C,分别将重组菌口服接种小鼠,检测小鼠的免疫应答,结果发现:① SL7207/pCI-C免疫鼠的CD3+CD4+ T细胞持续降低,而SL7207/pZW-C免疫鼠的CD3+CD4+ T细胞无明显改变;② SL7207/pCI-C免疫只诱导低水平抗HCV核心蛋白抗体,加强免疫对抗体阳转率及抗体水平无明显影响,而SL7207/pZW-C免疫组所有小鼠均产生较高水平的抗核心蛋白抗体。③ SL7207/pCI-C免疫鼠脾细胞的体外增殖活性、细胞毒性T细胞活性以及加强免疫对细胞免疫应答的增强作用均明显不及SL7207/pZW-C免疫鼠。结果提示:携带真核表达质粒pCI-C的沙门菌因在小鼠细胞内表达天然形式(结构以及磷酸化修饰)的HCV核心蛋白,可能通过对T细胞的免疫抑制作用而弱化免疫应答。而以携带原核表达质粒pZW-C的沙门菌免疫可避免这一问题,并具有接种方便,成本低廉等优点,从而可望作为基于HCV核心蛋白为靶抗原的HCV疫苗的候选免疫方式。 相似文献
8.
Sandra Kraeuter Kops Daniel K. Lowe William M. Bement A. Brian West 《Microbiology and immunology》1996,40(11):799-811
This study characterizes the transmigration of enteroinvasive Salmonella typhi in vitro, using a human intestinal epithelial cell line as a model of small intestinal epithelium. C2BBe cells, a subclone of CACO-2 with a highly differentiated enterocytic phenotype, were grown to maturity on Transwell filters. S. typhi Ty2 and the vaccine strain, Ty21a, the S. typhi mutant X7344 and parent strain SB130, and S. typhimurium 5771 in logarithmic phase were introduced to the upper chamber of the filter units. Numbers of bacteria in the lower chamber, TER and permeability of the monolayer to mannitol were measured over time. Monolayers were examined by light, electron and confocal microscopy to determine the pathway of bacterial transmigration, and intracellular bacteria were estimated by gentamicin assay. Epithelial cell injury was quantified by light microscopy. S. typhi transmigrated earlier and in larger numbers than S. typhimurium, inducing marked changes in electrical resistance and permeability. Unlike S. typhimurium, S. typhi selected epithelial cells in small number and caused their death and extrusion from the monolayers leaving holes through which S. typhi transmigrated. Ty2 consistently transmigrated in larger numbers and with more injury to monolayers than Ty21a. S. typhi crosses the monolayers of C2BBe cells by a paracellular route in contrast to the transcellular pathway described for other Salmonellae. This may be related to the unique pathophysiology of S. typhi infection and the restricted host specificity of this pathogen. In these assays the vaccine strain, Ty21a, is slightly less invasive than its parent, though more invasive than S. typhimurium. 相似文献
9.
Fumiko Nishikawa Eiji Kita Hideki Yamada Akira Nakano Shuzo Kashiba 《Microbiology and immunology》1994,38(2):129-137
L forms of Salmonella typhimurium LT2 conferred strong protection to a lethal challenge with its parental bacterium on innately hypersusceptible C3H/HeJ mice, and its minimal protective dose was approximately 150 L-forming units. Although L-form S. typhimurium was avirulent for C3H/HeJ mice, it multiplied slowly in both the liver and spleen with the maximal growth 2–3 weeks after immunization and thereafter it persisted in the liver until 24 weeks. Protective immunity began to work between 4 and 6 weeks after immunization, and it remained active as long as the L forms colonized the liver (until 24 weeks after immunization). Vaccination with the L form induced a population of T cells responding to L-form whole-cell lysate (WCL), while delayed-type hypersensitivity (DTH) to the extract of S. typhimurium was induced after the establishment of solid immunity. Moreover, neither T-cell responses nor DTH to heat-killed S. typhimurium was generated. In addition, antibody responses were elicited to WCL but not to heat-killed S. typhimurium. These results indicate that protection conferred by the L forms is attributable to the persistent colonization of the L forms rather than the presence of DTH, and also that Salmonella cytoplasmic antigens are involved in induction of immunological responses by vaccination with the L forms. 相似文献
10.
Protective immunities induced by porins from mutant strains of Salmonella typhimurium 总被引:4,自引:0,他引:4
The protective immunity against Salmonella typhimurium-infection in mice immunized with porins from mutant strains of S. typhimurium was studied. A high level of protection against S. typhimurium infection was achieved in mice immunized with native porins from S. typhimurium LT2 (wild-type strain) but not from S. typhimurium SH6017, SH6260, or SH5551 (mutant strains), which produce 34K, 35K, or 36K porin, respectively. Moreover, when mice were immunized with mixtures of 34K, 35K, and 36K porins (34K + 35K, 35K + 36K, 34K + 36K, or 34K + 35K + 36K porin) or LT2 porin heated at 100 C for 2 min in 2% SDS (heat-denatured LT2 porin), the degree of protective immunities in the mice was very much lower than that in the mice immunized with the native LT2 porin. However, antisera raised against these porins showed no significant differences of the antibody titer against LT2 porin or LT2 whole cells. On the other hand, mice immunized with the native LT2 porin--but not 34K, 35K, 36K, 34K + 35K + 36K, and the heat-denatured LT2 porins--exhibited significant levels of delayed-type hypersensitivity reaction and interleukin-2 production when they were elicited with whole cells of S. typhimurium LT2. These observations suggested that the high level of protection induced by the native LT2 porin immunization was dependent on the induction of cell-mediated immunity. 相似文献
11.
为研究LPS 2630表位模拟肽13L是否能诱导抗脂多糖(LPS)抗体的产生、对细菌攻击及内毒素休克的保护性反应,合成了模拟LPS表位的短肽13L.用合成肽13L-蓝载体(blue carrier,BC)交联物免疫Balb/C小鼠,观察小鼠体内抗LPS抗体产生的规律,并观察免疫小鼠细菌感染存活时间,用颈总动脉插管测定技术观察免疫小鼠内毒素休克的血压变化.结果显示,合成肽13L-BSA交联物能与兔抗鼠伤寒和大肠杆菌LPS抗血清及抗鼠伤寒LPS单抗结合,证明短肽13L可模拟LPS的抗原性.用13L-BC交联物免疫可诱发小鼠体内针对大肠杆菌LPS 2630和鼠伤寒沙门氏菌LPS 7261的抗体反应,该反应可被灭活大肠杆菌及两种LPS所加强,其抗体亚类主要为IgG2a,其次为IgG2b与IgM,而IgG1与IgG3含量极低.免疫13L-BC小鼠显示对细菌攻击的抵抗,与免疫BC对照小鼠比较,其存活时间分别为(12±1.3)天和(5.3±0.4)天(P〈0.01).免疫13L-BC小鼠对静脉注射LPS诱发内毒素休克的保护作用体现在血压下降幅度明显低于对照动物,在LPS 2630攻击后1、2、3及4h时两组动物血压明显差别(P〈0.05、P〈0.01、P〈0.05及P〈0.01),而LPS 7261攻击后1、2、3及4h时两组动物血压差别则略小于LPS 2630组(P〉0.05、P〈0.05、P〈0.05及P〈0.01).上述结果证明,LPS表位模拟肽13L交联物免疫小鼠可产生针对细菌攻击及内毒素休克的保护性效应,提示该模拟肽作为LPS交叉保护性疫苗候选的可行性. 相似文献
12.
Wan Noraini Wan Yusof Menaka Nagaratnam Chong-lek Koh Savithri Puthucheary Tikki Pang 《Microbiology and immunology》1993,37(8):667-670
Human mononuclear cells pre-labeled with [3H]arachidonic acid were shown to release metabolites following in vitro addition of heat-killed Salmonella typhi (HKST). The amount of label released was significantly higher than that seen with live S. typhi (LST). Addition of increasing amounts of HKST resulted in an increased release of metabolites. Enzyme immunoassay of the culture supernatants revealed that the bulk of the metabolite released was prostaglandin E2 (PGE2). Leukotriene B4 (LTB4) and leukotriene C4 (LTC4) were not detectable in the culture supernatants. The significance and implications of these results are discussed. 相似文献
13.
Gordon Dougan Duncan Maskell Derek Pickard Carlos Hormaeche 《Molecular & general genetics : MGG》1987,207(2-3):402-405
Summary Derivatives of the Salmonella typhi strain Ty2 carrying stable mutations in the aroA gene were isolated. The mutations were generated by transducing an aroA::Tn10 marker into Ty2 and selecting for derivatives which were tetracyline sensitive and dependent on aromatic compounds for growth. Isolates that did not revert to aromatic compound independence at a detectable frequency were obtained. An S. typhimurium derived aroA specific DNA probe was used to demonstrate the presence of DNA rearrangements in the aroA region of the chromosome of some of the S. typhi aroA mutants. Most of these isolates still expressed Vi antigen. Aromatic compound dependent mutants of S. typhi were less virulent in mice than S. typhi Ty2 following intraperitoneal challenge with bacteria suspended in mucin. Mice immunised with one of these mutants, named WBL85-1, were protected against a potentially lethal challenge of S. typhi Ty2. 相似文献
14.
The phoP locus influences processing and presentation of Salmonella typhimurium antigens by activated macrophages 总被引:5,自引:0,他引:5
Mary Jo Wick Clifford V. Harding Nicholas J. Twesten Staffan J. Normark John D. Pfeifer 《Molecular microbiology》1995,16(3):465-476
The destruction and processing of bacteria by activated macrophages facilitates the presentation of antigens to T cells and thereby promotes the induction of specific immunity. The PhoP-PhoQ regulatory system that controls the synthesis of many Salmonella proteins required for virulence and survival within macrophages is one mechanism that this particular intracellular pathogen has evolved to resist destruction. To address whether the phoP locus also influences antigen processing during the interaction of Salmonella typhimurium with macrophages, we tested the effect of phoP mutations on the processing and presentation of model antigens expressed by the bacteria. Activated macrophages processed phoP? bacteria with greater efficiency than wild-type bacteria, as measured by the response of antigen-specific T-hybridoma cells; Salmonella constitutively expressing PhoP were processed even less efficiently than wild-type Salmonella. After heat-inactivation, however, both wild-type and phoP? bacteria were efficiently processed. The altered processing and presentation efficiency was not due to differences in the level of antigen expressed by the bacteria or differences in the level of bacterial uptake by the macrophages. In addition, phoP-regulated gene expression was shown to influence processing of antigen phagocytosed independently of the bacteria. Thus, phoP-regulated gene products decrease the processing and presentation of S. typhimurium antigens, demonstrating a rote 1or this virulence locus in the inhibition of the induction of specific immunity. 相似文献
15.
Min‐Kyoung Shin Won‐Jung Lee Myung Hwan Jung Seung‐Bin Cha Seung‐Won Shin Anna Yoo Dae‐Hyuk Kim Han Sang Yoo 《Microbiology and immunology》2013,57(6):417-425
An oral delivery system based on ApxIIA#5‐expressed on Saccharomyces cerevisiae was studied for its potential to induce immune responses in mice. Murine bone marrow‐derived dendritic cells (DCs) stimulated in vitro with ApxIIA#5‐expressed on S. cerevisiae upregulated the expression of maturation and activation markers, leading to production of tumor necrosis factor‐α, interleukin (IL)‐1β, IL‐12p70 and IL‐10. Presentation of these activated DCs to cluster of differentiation CD4+ T cells collected from mice that had been orally immunized with the ApxIIA#5‐expressed on S. cerevisiae elicited specific T‐cell proliferation. In addition, the orally immunized mice had stronger antigen‐specific serum IgG and IgA antibody responses and larger numbers of antigen‐specific IgG and IgA antibody‐secreting cells in their spleens, Peyer's patches and lamina propria than did those immunized with vector‐only S. cerevisiae or those not immunized. Furthermore, oral immunization induced T helper 1‐type immune responses mediated via increased serum concentrations of IgG2a and an increase predominantly of IFN‐γ‐producing cells in their spleens and lamina propria. Our findings suggest that surface‐displayed ApxIIA#5‐expressed on S. cerevisiae may be a promising candidate for an oral vaccine delivery system for eliciting systemic and mucosal immunity. 相似文献
16.
Summary A combination of immunomagnetic separation and polymerase chain reaction (IMS-PCR) was used to detect Salmonella typhi in food and water samples. IMS was found to be an effective method for specific capture of S. typhi from artificially inoculated meat rinse samples. The bacteria could be detected within 6 h by IMS-PCR with a sensitivity of 105 cells. However, when tested in milk samples, the method was less effective. In comparison to conventional culture method, IMS-PCR is a rapid and specific method for detection of S. typhi and could be useful in outbreak situations for tracing the source of infection. 相似文献
17.
Masato Tsuda Akira Hosono Tsutomu Yanagibashi Satoshi Hachimura Kazuhiro Hirayama Kikuji Itoh Kyoko Takahashi Shuichi Kaminogawa 《Cytotechnology》2007,55(2-3):89-101
The development of allergy is related to differences in the intestinal microbiota. Therefore, it is suggested that the immune
responses induced by different genera of bacteria might be regulated through adaptive as well as innate immunity. In this
study, we examined whether antigen-specific immune responses were affected by stimulation with the different genera of intestinal
bacteria in vitro. Mesenteric lymph node (MLN) cells isolated from germ-free ovalbumin (OVA)-specific T cell receptor transgenic
(OVA-Tg) mice were stimulated with OVA and intestinal bacteria. Cecal contents from conventional mice but not germ-free mice
could induce OVA-specific cytokine production. Among the murine intestinal bacteria, Bacteroides acidofaciens (BA) enhanced OVA-specific IFN-γ and IL-10 production while Lactobacillus
johnsonii (LA) increased OVA-specific IL-10 production only. The expression of cell surface molecules and cytokine production by antigen-presenting
cells (APCs) from germ-free Balb/c mice were analyzed. BA increased the expression of MHC II and co-stimulatory molecules
on APCs compared with LA. BA increased IL-6 and IL-10 production but induced less IL-12p40 than LA. To examine the effects
of prior stimulation of APCs by intestinal bacteria on the induction of antigen-specific immune responses, cytokine production
was determined following co-culture with OVA, CD4+ T cells from OVA-Tg mice, and APCs which were pre-stimulated with the bacteria or not. APCs pre-stimulated with LA did not
enhance OVA-specific cytokine production while BA stimulated OVA-specific IL-10 production. These results suggest that the
prior stimulation of intestinal immunocytes by Lactobacillus might regulate excessive antigen-specific cytokine responses via APCs when compared with prior stimulation by Bacteroides. 相似文献
18.
Gene Transfer between Related Bacteria by Electrotransformation: Mapping Salmonella typhi Genes in Salmonella typhimurium
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Transfer of newly isolated mutations into a fresh background is an essential step of genetic analysis and strain construction. Gene transfer is hampered in Salmonella typhi and in other pathogenic bacteria by the lack of a generalized transduction system. We show here that this problem can be partially circumvented by using electrotransformation as a means for delivering S. typhi DNA into suitable S. typhi or Salmonella typhimurium recipients. Transferred DNA can recombine with the homologous region in the host chromosome. In one application of the method, mutations isolated in S. typhi were genetically mapped in S. typhimurium. 相似文献
19.
Toll‐like receptor 5 is not essential for the promotion of secretory immunoglobulin A antibody responses to flagellated bacteria
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20.
The engulfing, bactericidal and degrading activities toSalmonella typhi, strain ty2-4446 and 0-901 and toSalmonella enteritidis of guinea pig macrophages obtained from peritoneal exudate, spleen and bone marrow that were cultivated for 2–7 days, were
studied. The phagocytic activity was expressed as a total number of phagocytosed microbes and the number of viable bacteria,
released from mechanically disrupted macrophages. The ratio of phagocytosed bacteria to the original number of bacteria that
were introduced to macrophage cultures, were evaluated in per cents. No significant difference in phagocytic activity was
found between macrophages submitted to thein vitro cultivation and macrophages freshly isolated from the organism. Profound variations in phagocytic activity of cells were
found which were partially dependent on the dose of microbes employed for the infection of cultures. Furthermore, both the
engulfing and bactericidal activity of peritoneal macrophages toSalmonella typhi were found to be higher than in bone morrow macrophages.Salmonella typhi 0-901 microbes were phagocytosed by macrophages from bone marrow and peritoneal exudate much better thanSalmonella typhi ty2. In addition, a significant delay in bactericidal activity toSalmonella typhi ty2 of bone marrow macrophages in comparison to peritoneal macrophages was observed. The spleen macrophages possessed better
phagocytic and killing activity toSalmonella enteritidis than bone marrow macrophages. A striking difference was found as regards the intracellular growth ofSalmonella typhi andSalmonella gertneri: no multiplication ofSalmonella typhi within the peritoneal and bone marrow macrophages was observed during the 3–5 h cultivation, whereas on the other hand,Salmonella gertneri started to grow intracellularly within the 5 h cultivation in the bone marrow macrophages. 相似文献