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1.
Risk Manag Healthc Policy ; 16: 2469-2478, 2023.
Article in English | MEDLINE | ID: mdl-38024496

ABSTRACT

Purpose: Approximately 20% of couples face infertility challenges and struggle to conceive naturally. Despite advances in artificial reproduction, its success hinges on sperm quality. Our previous study used five machine learning (ML) algorithms, random forest, stochastic gradient boosting, least absolute shrinkage and selection operator regression, ridge regression, and extreme gradient boosting, to model health data from 1375 Taiwanese males and identified ten risk factors affecting sperm count. Methods: We employed the CART algorithm to generate decision trees using identified risk factors to predict healthy sperm counts. Four error metrics, SMAPE, RAE, RRSE, and RMSE, were used to evaluate the decision trees. We identified the top five decision trees based on their low errors and discussed in detail the tree with the least error. Results: The decision tree featuring the least error, comprising BMI, UA, ST, T-Cho/HDL-C ratio, and BUN, corroborated the negative impacts of metabolic syndrome, particularly high BMI, on sperm count, while emphasizing the link between good sleep and male fertility. Our study also sheds light on the potentially significant influence of high BUN on spermatogenesis. Two novel risk factors, T-Cho/HDL-C and UA, warrant further investigation. Conclusion: The ML algorithm established a predictive model for healthcare personnel to assess low sperm counts. Refinement of the model using additional data is crucial for improved precision. The risk factors identified offer avenues for future investigations.

2.
Food Sci Biotechnol ; 26(3): 715-721, 2017.
Article in English | MEDLINE | ID: mdl-30263596

ABSTRACT

Bostrycin, a red antibacterial agent produced by Nigrospora sp. no. 407, is considered for meat processing. To optimize production, the culture conditions of submerged fermentation (SmF) and solid-state fermentation (SSF) were investigated. The optimal SmF conditions were a medium containing 1.0% cane molasses and incubation at 30 °C and 150 rpm for 6 days. In SSF, other than bostrycin, less pigment was produced and the optimal ratio of bagasse to water was 1:2 for 10 days. The production and recovery rate of bostrycin by SmF were 120 mg/L and 40%, respectively. Bostrycin exhibited thermostable, pH-dependent color change and dose-dependent antibacterial activity against Clostridium botulinum. Bostrycin-modified meat turned strong red for at least 24 h and could not be removed by washing; bostrycin maintained its antibacterial activity with a bacteriostasis rate of 91% on Staphylcoccus aureus. This is an easy and inexpensive means of acquiring bostrycin from molasses and sugarcane.

3.
Food Chem ; 154: 282-90, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24518344

ABSTRACT

The choice of surfactants and cosurfactants for preparation of oral formulation in microemulsions is limited. In this report, a curcumin-encapsulated phospholipids-based microemulsion (ME) using food-grade ingredients soybean oil and soybean lecithin to replace ethyl oleate and purified lecithin from our previous study was established and compared. The results indicated soybean oil is superior to ethyl oleate as the oil phase in curcumin microemulsion, as proven by the broadened microemulsion region with increasing range of surfactant/soybean oil ratio (approx. 1:1-12:1). Further preparation of two formula with different particle sizes of formula A (30nm) and B (80nm) exhibited differential effects on the cytotoxicity of hepatocellular HepG2 cell lines. At 15µM of concentration, curcumin-ME in formula A with smaller particle size resulted in the lowest viability (approx. 5%), which might be explained by increasing intake of curcumin, as observed by fluorescence microscopy. In addition, the cytotoxic effect of curcumin-ME is exclusively prominent on HepG2, not on HEK293, which showed over 80% of viability at 15µM. The results from this study might provide an innovative applied technique in the area of nutraceuticals and functional foods.


Subject(s)
Curcumin/chemistry , Drug Carriers/chemistry , Lecithins/chemistry , Soybean Oil/chemistry , Cell Survival/drug effects , Chemistry, Pharmaceutical , Curcumin/toxicity , Drug Delivery Systems , Emulsions/chemistry , HEK293 Cells , Hep G2 Cells , Humans , Lecithins/toxicity , Particle Size , Solubility , Soybean Oil/toxicity , Surface-Active Agents/chemistry , Surface-Active Agents/toxicity
4.
Enzyme Microb Technol ; 50(6-7): 287-92, 2012 May 10.
Article in English | MEDLINE | ID: mdl-22500894

ABSTRACT

Bostrycin, a red antibacterial agent with tetrahydroanthraquinone structure, has been isolated from Nigrospora sp. No. 407. This study investigated the potential antibacterial and multifunctional properties of matrixes through immobilization of bostrycin on their surface for immobilization of protein and prevention of bacterial growth. Bostrycin was immobilized on nonwoven polypropylene (PP) fabric by a technique using glutaraldehyde and polyethyleneimine for the activation of the surface. Glucose oxidase immobilized on bostrycin-treated nonwoven PP fabric showed high activity. The immobilization process improved thermal stability of the enzymes. During repeated assay for 30 cycles, the enzyme activity dropped to only 70% of the initial activity. Both bostrycin-treated nonwoven PP fabric sample and subsequently immobilized glucose oxidase sample on the surface also still exhibited a bacteriostatic effect. This is the first study to show that bostrycin is a promising coupling agent for surface modification on matrix and its potential applications in protein immobilization and biomaterial-centered infection.


Subject(s)
Anthraquinones/chemistry , Anti-Bacterial Agents/pharmacology , Ascomycota/enzymology , Enzymes, Immobilized/chemistry , Glucose Oxidase/chemistry , Textiles , Anthraquinones/metabolism , Anthraquinones/pharmacology , Anti-Bacterial Agents/biosynthesis , Anti-Bacterial Agents/chemistry , Biotechnology/methods , Clostridium botulinum/drug effects , Enzyme Stability , Enzymes, Immobilized/metabolism , Glucose Oxidase/metabolism , Microbial Sensitivity Tests , Polypropylenes/chemistry , Staphylococcus aureus/drug effects , Surface Properties
5.
Int J Nanomedicine ; 7: 941-51, 2012.
Article in English | MEDLINE | ID: mdl-22393291

ABSTRACT

There is increasing interest in using natural products as anticancer agents, as many have antioxidative properties that may help to prevent cellular damage that can lead to cancer. In addition, there is the expectation that many natural products will have low toxicity and few side effects. However, most anticancer and antioxidative agents are hydrophobic, reducing their bioavailability in vivo and making them problematic to deliver. Curcumin provides a good model system for study. In low doses it shows both anticancer and antioxidation effects, whereas in high doses and delivered locally it could be cytotoxic for cancer cells. In this paper, curcumin microemulsions were formed with food-grade chemicals, including soybean lecithin, soybean oil, and Tween 80, a Food and Drug Administration-approved surfactant. The optimized composition formed curcumin microemulsions with a mean size of 40-50 nm, carrying a concentration of curcumin as high as 15 µM. The stability of curcumin microemulsions refrigerated at 5°C over at least 968 days was assessed by size distribution and zeta potential. The effects of low-frequency ultrasound on two oral squamous cell carcinoma cell lines (OSCC-4 and OSCC-25), and the synergy between treatment with curcumin microemulsions and low-frequency sonic stimulation, were tested. Finally, microscopic imaging of the cells confirmed the toxic effects of the curcumin microemulsions, showing damaged and ruptured cells after treatment. Brief exposure to the curcumin-containing microemulsions did have cytotoxic effects, but the addition of ultrasound strongly enhanced those effects, especially on OSCC-25 cells.


Subject(s)
Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Squamous Cell/drug therapy , Curcumin/administration & dosage , Mouth Neoplasms/diagnostic imaging , Mouth Neoplasms/drug therapy , Ultrasonic Therapy/methods , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Survival/drug effects , Combined Modality Therapy , Curcumin/chemistry , Delayed-Action Preparations , Drug Carriers/administration & dosage , Drug Carriers/chemistry , Drug Stability , Emulsions , Humans , Mouth Neoplasms/pathology , Nanoparticles/chemistry , Particle Size , Ultrasonography
6.
Vaccine ; 29(44): 7740-6, 2011 Oct 13.
Article in English | MEDLINE | ID: mdl-21835218

ABSTRACT

Actinobacillus pleuropneumoniae is a gram-negative bacterial pathogen that causes swine pleuropneumonia, a highly contagious and often fatal disease that occurs worldwide. Our previous study showed that DNA vaccines encoding Apx exotoxin structural proteins ApxIA and/or ApxIIA, are a promising novel approach for immunization against the lethal challenge of A. pleuropneumoniae serotype 1. Vaccination against A. pleuropneumoniae is impeded by the lack of vaccines inducing reliable cross-serotype protection. Type IV fimbrial protein ApfA has been shown to be present and highly conserved in various serotypes of A. pleuropneumoniae. A novel DNA vaccine encoding ApfA (pcDNA-apfA) was constructed to evaluate the protective efficacy against infection with A. pleuropneumoniae serotype 2. A significant antibody response against pilin was generated following pcDNA-apfA immunization, suggesting that it was expressed in vivo. The IgG subclass (IgG1 and IgG2a) analysis indicates that the pcDNA-apfA vaccine induces both Th1 and Th2 immune responses. The IgA analysis shows that mucosal immunity could be enhanced by this DNA vaccine. Nevertheless, the strong antibody response induced by pcDNA-apfA vaccine only provided limited 30% protective efficacy against the serotype 2 challenge. These results in this study do not coincide with that the utility of type IV pilin is a good vaccine candidate against other infectious pathogens. It indicates that pilin should play a limited role in the development of a vaccine against A. pleuropneumoniae infection.


Subject(s)
Actinobacillus Infections/veterinary , Actinobacillus pleuropneumoniae/immunology , Bacterial Vaccines/immunology , Fimbriae Proteins/immunology , Pleuropneumonia/prevention & control , Vaccines, DNA/immunology , Actinobacillus Infections/immunology , Actinobacillus Infections/prevention & control , Actinobacillus pleuropneumoniae/genetics , Animals , Antibodies, Bacterial/blood , Bacterial Vaccines/administration & dosage , Bacterial Vaccines/genetics , Disease Models, Animal , Fimbriae Proteins/administration & dosage , Fimbriae Proteins/genetics , Immunity, Mucosal , Immunoglobulin A/blood , Immunoglobulin G/blood , Mice , Mice, Inbred BALB C , Pleuropneumonia/immunology , Survival Analysis , Th1 Cells/immunology , Th2 Cells/immunology , Vaccines, DNA/administration & dosage , Vaccines, DNA/genetics
7.
J Clin Virol ; 52(1): 11-6, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21767983

ABSTRACT

BACKGROUND: Taiwan launched a nationwide infant vaccination program for hepatitis B (HB) in 1984. OBJECTIVES: This study evaluated the seroprevalence of hepatitis B virus (HBV) and the incidence of high alanine aminotransferase (ALT) level among young adults prior to, during, and since the introduction of the nationwide HBV vaccination program. STUDY DESIGN: Researchers recruited 101,584 freshmen (male:female=1.114:1; mean age, 18.5±0.5 years) from 21 universities between 1995 and 2009 (birth cohorts 1977-1991) in Taiwan, testing for serum hepatitis B surface antigens (HBsAg), hepatitis e antigens (HBeAg), antibodies against HBsAg (anti-HBs), and liver function tests, including ALT and aspartate aminotransferase (AST). RESULTS: The results showed that the prevalence of HBsAg decreased significantly from 14.3% in 1995 to 1.1% in 2009 and the seroprevalence of HBeAg decreased significantly from 5.9% in 1995 to 0.3% in 2009. Seroconversion to anti-HBs maintained a steady rate above 50% between 1995 and 2007, but declined considerably to 36.6% and 36.4% in 2008 and 2009, respectively. Subject with HBeAg seropositivity was in 43.94% of HBV carriers. Double seronegativity for HBsAg and anti-HBs was observed in 2007 (47.8%), 2008 (62.3%), and 2009 (62.5%). High ALT level was observed in 5.74% of the subjects, particular among HBV-carriers (16.5% of HBV carrier vs. 5.0% of non-HBV carrier; ORs, 3.733; 95% CIs, 3.463-4.023, p<0.0001). Subjects with high ALT level were significantly positively associated with HBeAg (10.5% of HBeAg seropositive vs. 1.9% of HBeAg seronegative; ORs, 6.195; 95%CI, 5.629-6.818; p<0.0001). Male subjects were more easily infected by HBV than female subjects were (HBsAg, ORs, 1.355, 95% CI, 1.283-1.431; HBeAg, ORs, 1.324, 95% CI, 1.218-1.439, p<0.0001), and significantly more male subjects had high ALT levels than female subjects did (ORs, 4.087; 95% CI, 3.819-4.375, p<0.0001). CONCLUSIONS: The mass vaccination program successfully reduced the HBV carrier rate and prevalence of chronic hepatitis B in Taiwan. However, the low percentage of anti-HBV in 2008 and 2009 remains unresolved.


Subject(s)
Hepatitis B Vaccines/immunology , Hepatitis B/prevention & control , Adolescent , Carrier State/epidemiology , Carrier State/immunology , Female , Hepatitis B/blood , Hepatitis B/epidemiology , Hepatitis B/immunology , Hepatitis B Antibodies/blood , Hepatitis B Antibodies/immunology , Hepatitis B Surface Antigens/blood , Hepatitis B Surface Antigens/immunology , Humans , Infant , Infant, Newborn , Liver Function Tests , Male , Mass Vaccination , Retrospective Studies , Seroepidemiologic Studies , Taiwan/epidemiology , Young Adult
8.
Vaccine ; 28(50): 7956-62, 2010 Nov 23.
Article in English | MEDLINE | ID: mdl-20933041

ABSTRACT

Recombinant parvovirus VP2 (rVP2) was formulated with different types of adjuvant, including aluminum adjuvant and CpG oligodeoxynucleotides (ODNs), and the immunological responses after vaccination in ducks were examined. In comparison with the control group, production of rVP2-specific antibodies, expression of cytokines in peripheral blood mononuclear cells (PBMC) stimulated by rVP2, and percentage of CD4(+)/CD8(+) cells in PBMC were significantly increased in ducks immunized with rVP2 formulated with CpG ODNs containing 3 copies of GACGTT motif. CpG ODNs with GACGTT motifs might be used to improve the efficacy of vaccines for ducks.


Subject(s)
Capsid Proteins/immunology , Ducks/immunology , Oligodeoxyribonucleotides/immunology , Parvoviridae Infections/veterinary , Parvovirus/immunology , Poultry Diseases/prevention & control , Adjuvants, Immunologic/pharmacology , Animals , Antibodies, Viral/blood , CD4-CD8 Ratio , Cell Proliferation , Cytokines/immunology , Leukocytes, Mononuclear/immunology , Parvoviridae Infections/prevention & control , Recombinant Proteins/immunology
9.
Biochem Biophys Res Commun ; 387(3): 617-22, 2009 Sep 25.
Article in English | MEDLINE | ID: mdl-19632196

ABSTRACT

Phage display is effective in screening peptides that mimic venom's neutralizing epitopes. A phage display cyclized heptapeptide library (C7C library) was panned with purified divalent antivenin IgG, which neutralizes Naja naja atra venom (NAV) and Bungarus multicinctus venom (BMV). The selected heptapeptide sequences were aligned with known protein sequences of NAV and BMV in GenBank. One of the four consensus sequences, L/PKSSLL, mimicked the crucial epitope on Loop III of Taiwan cobra cardiotoxin that is associated with the venom's lethal potency. In dot blot analysis, several clones showed varying reactivities for NAV monovalent antivenin and lesser cross-reactions with BMV monovalent antivenin. The KSSLLRN-carrying phage occurred four times in selected clones and showed the strongest reactivity to NAV monovalent antivenin. Furthermore, the QDSLLPS-carrying phage also presented significant dot blot signal, indicating that the SLL sequence shared by these two clones may be a crucial antibody-binding site.


Subject(s)
Cobra Cardiotoxin Proteins/chemistry , Cobra Cardiotoxin Proteins/immunology , Consensus Sequence , Epitopes/chemistry , Epitopes/immunology , Molecular Mimicry , Amino Acid Sequence , Animals , Antibodies/immunology , Cobra Cardiotoxin Proteins/genetics , Epitope Mapping , Epitopes/genetics , Female , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Neutralization Tests , Peptide Library , Protein Structure, Secondary
10.
Vaccine ; 27(34): 4565-70, 2009 Jul 23.
Article in English | MEDLINE | ID: mdl-19520199

ABSTRACT

Actinobacillus pleuropneumoniae is the major etiological agent of swine pleuropneumonia that causes critical economic losses in swine industry. The use of DNA vaccines encoding Apx exotoxin structural proteins is a promising novel approach for immunization against A. pleuropneumoniae. The goal of this study was to design DNA vaccines which encode the gene of ApxIA or ApxIIA, and to evaluate the elicited immune responses and protective efficacy in mice. Significant humoral immune responses were induced by these DNA vaccines through intramuscular immunization. The IgG subclass (IgG1 and IgG2a) analysis indicates that divalent DNA vaccine induces both Th1 and Th2 immune responses. The protective efficacy was evaluated by the survival against lethal challenge with A. pleuropneumoniae serotype 1. The groups of vaccination with pcDNA-apxIA or divalent (pcDNA-apxIA and pcDNA-apxIIA) DNA vaccine provided protective efficacy significantly higher than that of the negative control groups (P<0.05). However, pcDNA-apxIIA vaccine conferred protection was limited and not significant than that of the negative control groups (P>0.05). These results show that the divalent DNA vaccine could confer the best protection. This finding indicates that DNA immunization should facilitate the development of a 'third-generation' of vaccines and provide a novel strategy against A. pleuropneumoniae infection.


Subject(s)
Actinobacillus Infections/veterinary , Actinobacillus pleuropneumoniae/immunology , Bacterial Proteins/immunology , Hemolysin Proteins/immunology , Swine Diseases/prevention & control , Vaccines, DNA/immunology , Actinobacillus Infections/immunology , Actinobacillus Infections/prevention & control , Actinobacillus pleuropneumoniae/genetics , Animals , Antibodies, Bacterial/blood , Bacterial Proteins/genetics , Female , Hemolysin Proteins/genetics , Immunoglobulin G/blood , Injections, Intramuscular , Mice , Mice, Inbred BALB C , Survival Analysis , Swine , Swine Diseases/immunology , Vaccines, DNA/administration & dosage
11.
Appl Microbiol Biotechnol ; 71(2): 211-21, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16195795

ABSTRACT

Biotin is an important nutritional supplement but is difficult to manufacture effectively. Here we present a trial of biotin production using the food yeast Candida utilis. In this system, we cloned the C. utilis biotin synthase (BIO2) gene, the gene of the rate-limiting enzyme for biotin biosynthesis, and assembled it under the control of a strong promoter. A series of plasmids were constructed to direct the integration of the BIO2 gene, either high-copy integration with 18S rDNA fragment or low-copy integration with URA3 or HIS3 fragment. The BIO2 gene can be successfully integrated into the C. utilis chromosome and can drive biotin production using these plasmids. The biotin yield in this system can reach 100-fold above the endogenous level in a small-scale culture. Although the biotin production is not stable if the selection pressure is removed, this system has the potential to produce biotin-rich feed or food additives directly without the requirement of further purification.


Subject(s)
Biotin/biosynthesis , Candida/metabolism , Industrial Microbiology/methods , Sulfurtransferases/metabolism , Biotin/genetics , Candida/genetics , Cloning, Molecular , DNA, Fungal/chemistry , DNA, Fungal/genetics , Mutagenesis, Site-Directed , Plasmids/genetics , Plasmids/metabolism , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombination, Genetic , Sulfurtransferases/genetics , Transformation, Genetic
12.
J Immunol Methods ; 304(1-2): 15-29, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16054642

ABSTRACT

Phage display techniques have been widely employed to map the epitope structures which served as the basis for developing molecular vaccines. In the present study, we applied this technique to map the epitopes of Mycoplasma hyopneumoniae, the etiologic agent causing swine enzootic pneumonia, and evaluated directly the immune responses in mice of the selected phage-displayed epitopes (phagotopes). Two phage-displayed random peptide libraries were biopanned with the protein A-purified IgG of the rabbit anti-M. hyopneumoniae hyperimmune serum and the selected phage clones were sequenced and analyzed. Some of the inserts of the selected phagotopes showed a good match with the known proteins of M. hyopneumoniae. Others, which did not match with any known proteins, but shared extensive homology with each other, were clustered and classified as the conformational epitopes of M. hyopneumoniae. To evaluate the potential of using these phagotopes as effective vaccines, several phage clones were chosen to immunize mice. IgA coproantibody, IgA in bronchoalveolar lavage fluid and serum IgG responses were assayed. The serum raised by the phage clones clearly recognized several major mycoplasmal proteins indicating that the phagotope-induced immune responses were antigen-specific. The stronger IgG1 response revealed that the immune responses of the epitope-displaying phage were mainly through Th2 activation. The growth inhibition assay showed that the selected phage clones CS4 and varphi58 are potential vaccine candidates and suggested that the mycoplasmal 97 kDa, 56 kDa, 30 kDa and 23 kDa proteins may play important roles in the immune responses. The present work demonstrates that the whole epitope profile of a microorganism can be obtained through screening the phage displayed peptide libraries with the hyperimmune serum and reveals the potential of using epitope-displaying phages as peptide vaccines.


Subject(s)
Bacteriophage M13/immunology , Epitope Mapping/methods , Epitopes/immunology , Mycoplasma/immunology , Peptide Library , Adhesins, Bacterial/genetics , Adhesins, Bacterial/immunology , Administration, Intranasal , Amino Acid Sequence , Animals , Antibodies, Bacterial/biosynthesis , Antibodies, Viral/biosynthesis , Bacterial Vaccines/administration & dosage , Bacterial Vaccines/immunology , Bacteriophage M13/growth & development , Female , Growth Inhibitors/administration & dosage , Growth Inhibitors/immunology , Immunoglobulin G/biosynthesis , Injections, Intraperitoneal , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Rabbits , Swine
13.
J Bacteriol ; 187(6): 1884-91, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15743934

ABSTRACT

The anti-TRAP protein (AT), encoded by the rtpA gene of Bacillus subtilis, can bind to and inhibit the tryptophan-activated trp RNA-binding attenuation protein (TRAP). AT binding can prevent TRAP from promoting transcription termination in the leader region of the trp operon, thereby increasing trp operon expression. We show here that AT levels continue to increase as tryptophan starvation becomes more severe, whereas the TRAP level remains relatively constant and independent of tryptophan starvation. Assuming that the functional form of AT is a trimer, we estimate that the ratios of AT trimers per TRAP molecule are 0.39 when the cells are grown under mild tryptophan starvation conditions, 0.83 under more severe starvation conditions, and approximately 2.0 when AT is expressed maximally. As the AT level is increased, a corresponding increase is observed in the anthranilate synthase level. When AT is expressed maximally, the anthranilate synthase level is about 70% of the level observed in a strain lacking TRAP. In a nutritional shift experiment where excess phenylalanine and tyrosine could potentially starve cells of tryptophan, both the AT level and anthranilate synthase activity were observed to increase. Expression of the trp operon is clearly influenced by the level of AT.


Subject(s)
Bacillus subtilis/genetics , Bacillus subtilis/metabolism , Bacterial Proteins/genetics , RNA-Binding Proteins/genetics , Transcription Factors/genetics , Tryptophan/metabolism , Anthranilate Synthase/genetics , Anthranilate Synthase/metabolism , Bacillus subtilis/growth & development , Bacterial Proteins/metabolism , Gene Deletion , Gene Expression Regulation, Bacterial , Genotype , Operon/genetics , Phenotype , RNA-Binding Proteins/metabolism , Transcription Factors/metabolism
14.
J Immunol Methods ; 276(1-2): 175-83, 2003 May 01.
Article in English | MEDLINE | ID: mdl-12738371

ABSTRACT

Phage-displayed peptide systems have been used to identify the immunogenic epitopes and to develop the design of peptide-based or peptide-displaying phages themselves as vaccine candidates. To estimate the humoral immunity of phage-based vaccine, it is necessary to evaluate the antibody response specifically directed at the displayed peptide. Enzyme-linked immunosorbent assays (ELISAs) and Western blot analysis are commonly used for this purpose. However, using these methods, it is not easy to distinguish the antibody response against phage coat protein or the antibody response specific to the displayed peptide. The purified anti-Mycoplasma hyopneumoniae IgG was used to screen heptapeptides displaying on the pIII coat protein of M13 phage. Four selected phage clones were chosen to immunize mice. In order to evaluate the specific antibody response that is directed against heptapeptides, advantage was taken of the natural property of M13 phage to infect Escherichia coli, which is mediated by the pIII coat protein binding with the F pili of E. coli, and plaque reduction tests were performed to assess the specificity of antibody response. By comparing the number of plaques produced by the different phages (which are the same except for the displayed peptides) neutralized by the antiserum, we could demonstrate that the specificity of antibody response is directed against the peptide displayed on pIII coat protein. The results described here indicate that plaque reduction test is a convenient and more precise method to detect the antibody against the phage-displayed peptide.


Subject(s)
Antibodies, Bacterial/immunology , Bacteriophage M13/growth & development , DNA-Binding Proteins/immunology , Peptide Library , Viral Fusion Proteins/immunology , Viral Plaque Assay/methods , Amino Acid Sequence , Animals , Antibodies, Bacterial/blood , Antibodies, Bacterial/isolation & purification , Antibody Specificity , Bacteriophage M13/genetics , Capsid Proteins , DNA-Binding Proteins/genetics , Escherichia coli/virology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin G/isolation & purification , Mice , Mice, Inbred BALB C , Mycoplasma/immunology , Oligopeptides/chemistry , Oligopeptides/immunology , Rabbits , Recombinant Fusion Proteins/immunology , Sequence Alignment , Viral Fusion Proteins/genetics
15.
Infect Immun ; 71(3): 1155-60, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12595427

ABSTRACT

Mycoplasma hyopneumoniae is the etiological agent of swine enzootic pneumonia, a chronic nonfatal disease affecting pigs of all ages. The goal of this study was to design DNA vaccines by constructing plasmid pcDNA3/P42, carrying the heat shock protein gene P42 of M. hyopneumoniae, and to evaluate the immune responses elicited in BALB/c mice. The expression of P42 was first examined in transfected NIH 3T3 cells by reverse transcription-PCR to ensure that the construct was functional. The humoral and cell-mediated immune responses induced by the plasmid were further evaluated in BALB/c mice through intramuscular injection. Both immunoglobulin G1 (IgG1) and IgG2a levels were 64 times those of the control groups during the first 8 weeks. The levels of interleukin-2 (IL-2), IL-4, and gamma interferon mRNAs in the immunized animals were elevated, and the proliferation of spleen cells was also enhanced in the immunized animals. The results indicate that pcDNA3/P42 DNA immunization induces both Th1 and Th2 immune responses. In addition, antiserum from the immunized animals was found to inhibit the growth of M. hyopneumoniae. The present study reveals that DNA vaccination could be a new strategy against infection by M. hyopneumoniae and may have potential for developing vaccines for other infectious diseases as well.


Subject(s)
Bacterial Vaccines/immunology , Heat-Shock Proteins/immunology , Mycoplasma/immunology , Saccharomyces cerevisiae Proteins , Vaccines, DNA/immunology , 3T3 Cells , Animals , CpG Islands , Cytokines/genetics , Female , Heat-Shock Proteins/genetics , Mice , Mice, Inbred BALB C , Mycoplasma/growth & development , Plasmids , RNA, Messenger/analysis , Vaccination
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