1
|
Liang M, Zhang T, Liu X, Fan Y, Xia S, Xiang Y, Liu Z, Jinnian L. Development of an indirect competitive enzyme-linked immunosorbent assay based on the multiepitope peptide for the synchronous detection of staphylococcal enterotoxin A and G proteins in milk. J Food Prot 2015; 78:362-9. [PMID: 25710152 DOI: 10.4315/0362-028x.jfp-14-323] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Staphylococcal food poisoning (SFP), one of the most common foodborne diseases, results from ingestion of staphylococcal enterotoxins (SEs) in foods. In our previous studies, we found that SEA and SEG were two predominant SE proteins produced by milkacquired S. aureus isolates. Here, a tandemly arranged multiepitope peptide (named SEAGepis) was designed with six linear B-cell epitopes derived from SEA or SEG and was heterologously expressed. The SEAGepis-specific antibody was prepared by immunizing rabbit with rSEAGepis. Then, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on rSEAGepis and the corresponding antibody was developed to simultaneously detect SEA and SEG. Under the optimized conditions, the ic-ELISA standard curve for rSEAGepis was constructed in the concentration range of 0.5 to 512 ng/ml, and the average coefficients of variation of intra- and interassay were 4.28 and 5.61% during six standard concentrations. The average half-maximal inhibitory concentration was 5.07 ng/ml, and the limit of detection at a signal-to-noise ratio of 3 was 0.52 ng/ml. The anti-rSEAGepis antibody displayed over 90% cross-reactivity with SEA and SEG but less than 0.5% cross-reactivity with other enterotoxins. Artificially contaminated milk with different concentrations of rSEAGepis, SEA, and SEG was detected by the established ic-ELISA; the recoveries of rSEAGepis, SEA, and SEG were 91.1 to 157.5%, 90.3 to 134.5%, and 89.1 to 117.5%, respectively, with a coefficient of variation below 12%. These results demonstrated that the newly established ic-ELISA possessed high sensitivity, specificity, stability, and accuracy and could potentially be a useful analytical method for synchronous detection of SEA and SEG in milk.
Collapse
Affiliation(s)
- Mingyan Liang
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China
| | - Tingting Zhang
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China
| | - Xuelan Liu
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China
| | - Yanan Fan
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China
| | - Shenglin Xia
- Center of Animal Epidemic Disease Prevention and Control, 460 Liming Avenue, Wuhu 241000, Anhui, People's Republic of China
| | - Yiqing Xiang
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China
| | - Ziqi Liu
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China
| | - Li Jinnian
- College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang Avenue, Hefei 230036, Anhui, People's Republic of China.
| |
Collapse
|
2
|
Derkach KV, Shpakova EA, Zharova OA, Shpakov AO. The metabolic changes in rats immunized with BSA conjugate of peptides derived from the N-terminal region of type 4 melanocortin receptor. DOKL BIOCHEM BIOPHYS 2014; 458:163-6. [DOI: 10.1134/s1607672914050019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Indexed: 11/23/2022]
|
3
|
Park SY, Kim HJ, Seo JY, Choi EY, Oh SW. Production of an epitope-specific antibody using recombinant repetitive oligonucleotides. Anim Cells Syst (Seoul) 2014. [DOI: 10.1080/19768354.2014.942362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
4
|
Design and evaluation of a tandemly arranged outer membrane protein U (OmpU) multi-epitope as a potential vaccine antigen against Vibrio mimicus in grass carps (Ctenopharyngodon idella). Vet Immunol Immunopathol 2014; 160:61-9. [PMID: 24751414 DOI: 10.1016/j.vetimm.2014.03.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 03/18/2014] [Accepted: 03/27/2014] [Indexed: 01/07/2023]
Abstract
Vibrio mimicus (V. mimicus) is an extracellular pathogen that causes ascites disease in aquatic animals. In our previous studies, the outer membrane protein U (OmpU) of V. mimicus has been proven to be a protective antigen, and several mimotopes of the protein were identified. Here, a tandemly arranged multi-epitope peptide (named 6EPIS) was designed with six mimotopes and heterologously expressed. Then, the immunoprotection efficacy of recombinant 6EPIS (r6EPIS) was evaluated in grass carps (Ctenopharyngodon idella) by determining relative percentage survival (RPS), specific immunoglobulin M (IgM) antibody titer, and transcriptional levels of immune-related genes of inoculated grass carps. Fish vaccinated with r6EPIS via intraperitoneal injection exhibited 85.71% RPS over the control, when challenged with V. mimicus. The enzyme-linked immunosorbent assay titer of specific IgM antibodies against r6EPIS reached 1:12,800 on Day 28 post the primary immunization. After 28 days post immunization, the transcriptional level of total IgM mRNA was significantly higher in the r6EPIS-vaccinated fish than in those vaccinated with recombinant OmpU, inactivated bacterin and rHis tag peptide (p<0.05). In addition, the transcription levels of interleukin-1β and tumor necrosis factor-α genes in the spleen and head kidney of r6EPIS-vaccinated fish were significantly increased during the period of immunization and early phase of infection, while the transcription level of interleukin-10 gene was significantly increased from Day 3 to 7 post challenge, compared to the control level. These results show that r6EPIS was highly immunogenic and could elicit strong protective immune responses. It may be an attractive vaccine candidate against V. mimicus infection.
Collapse
|
6
|
Tian H, Xiao Y, Zhu M, Chen YH. HIV epitope-peptides in aluminum adjuvant induced high levels of epitope-specific antibodies. Int Immunopharmacol 2001; 1:763-8. [PMID: 11357888 DOI: 10.1016/s1567-5769(01)00017-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Some neutralizing epitopes on HIV-1 envelope proteins were shown to induce antibodies that could effectively inhibit the infection of different HIV-1 strains in vitro. But only very low levels of antibodies to these epitopes were determined in the HIV-1 infected individuals. In this study, the aluminum (alum) adjuvant to increase the immunogenicity of the neutralizing epitopes was used. Three epitope-peptides [C-(ELDKWAG)4, C-(RILAVERYLKD-G)2 and C-(GPGRAFY)2], which contain three epitopes (ELDKWA, RILAVERYLKD, GPGRAFY) from the HIV-1 Env proteins, were synthesized and conjugated to carrier protein keyhole limpet hemocyanin (KLH). The epitope-vaccines C-(ELDKWAG)4-KLH and C-(RILAVERYLKD-G)2-KLH in alum induced high levels of epitope-specific antibodies recognizing the epitopes from epitope-peptides C-(ELDKWAG)4 and C-(RILAVERYLKD-G)2, as well as the gp41 C-domain peptides P2 [C-TSLIHSLIEESQNQQEKNEQELLELDKWA (aa 646-674)] and P1 [LQARILAVERYLKDQQL (aa 583-599)] and the recombinant soluble gp41 (rsgp41) bearing both epitopes (antibody titer in rabbit sera was 1:12800-25,600 dilution). Immunoblotting analysis demonstrated that the antibodies in both antisera bound to rsgp41, indicating that both antibodies recognized the natural epitopes on rsgp41 protein. The epitope-vaccines C-(GPGRAFY)2-KLH induced moderate GPGRAFY epitope-specific antibody response with a titer of 1:6,400. In contrast, as it was demonstrated in previous studies, the immunization with rgp160 induced weak antibody response to these three epitopes (titer of 1:400-1600). This suggests that epitope-peptides conjugated to KLH when infected with alum significantly increases immunogenicity of gp41 neutralizing epitopes providing a hope for the development of an HIV-1 vaccine.
Collapse
Affiliation(s)
- H Tian
- Research Center for Medical Science and Department of Biological Science and Technology, Tsinghua University, Beijing, People's Republic of China
| | | | | | | |
Collapse
|