A viral Antigen is an antigen with multiple antigenicities that is protein in nature, strain-specific, and closely associated with the virus particle. A viral antigen is a protein encoded by the viral genome.A viral protein is an antigen specified by the viral genome that can be detected by a specific immunological response.
Viruses are infectious pathogens that cause serious diseases & major threats for global public health, such as influenza, hepatitis, & AIDS. Virus is a sub-micrometer particle that has DNA or RNA packed in a shell called capsid. Viral antigens protrude from the capsid and often fulfill important function in docking to the host cell, fusion, and injection of viral DNA/RNA. Antibody-based immune responses form a first layer of protection of the host from viral infection; however, in many cases a vigorous cellular immune response mediated by T-cells and NK-cells is required for effective viral clearance. When cellular immunity is unable to clear the virus, the infection can become chronic, and serum antibodies to the viral pathogen are used as first indicator for the diagnosis of the disease.
ELISAs provide a valuable tool in the detection and diagnosis of virus infection. The ability to produce recombinant viral proteins will ensure that future ELISAs are safe, specific and rapid. Even when a virus cannot be cultured, provided gene sequence is available, it is possible to rapidly respond to emerging viruses and new viral strains of existing pathogens.
Recombinant viral antigens contain part of viral sequence meaning that the recombinant antigen contains a region which can be recognized by different antibodies produced by different individuals. This reduces the risk of false negatives which can occur with synthetic peptides, which contain only a small portion of the entire protein. If an individual infected with a viral antigen makes antibodies to a part of the protein not included in the synthetic peptides, a false negative results.
Recombinant viral protein usually contains a fusion protein/partner which produces superior attachment to assay surfaces such as wells. For this reason, smaller amounts of recombinant protein will produce the same results as larger amounts of unfused protein. The choice of fusion partner prevents false positives, allowing superior adhesion without incorrect results.
Recombinant Viral proteins are expressed in bacteria, yeast, mammalian cells, and viruses. E. Coli cells were first to be used for this purpose but the expressed proteins were not glycosylated, which was a major drawback since many of the immunogenic proteins of viruses such as the envelope glycoproteins, were glycosylated. Nevertheless, in many instances, it was demonstrated that the non-glycosylated protein backbone was just as immunogenic. The obvious advantage of recombinant viral antigens is that they are available in unlimited quantities and the production and quality control processes is simple.
Advantages of defined using recombinant viral antigens:
1. Production and quality control is simple.
2. No nucleic acids or other viral or external proteins, therefore less toxic.
3. Safer in cases where viruses are oncogenic or establish a persistent infection.
4. Feasible even if virus cannot be cultivated
1. May be less immunogenic than conventional inactivated whole-virus vaccines.
2. Requires adjuvant .
3. Fails to elicit CMI.
Facts about Viral Antigens:
1. A Viral Protein Mimics its Way into cells.
2. Viral Protein Helps Infected T Cells Stick To Uninfected Cells.
3. The Viral Protein A238L Inhibits Cyclooxygenase-2 Expression through a Nuclear Factor of Activated T Cell-dependent Trans-activation Pathway.
4. Viral Protein is an effective preventative against ear infection.
5. HIV-1 Viral Protein R Induces Apoptosis via a Direct Effect on the Mitochondrial Permeability Transition Pore.
6. The Level of Viral Antigen Presented by Hepatocytes Influences CD8 T-Cell Function.
7. Antigen-presenting cells from calves persistently infected with bovine viral diarrhea virus, a member of the Flaviviridae, are not compromised in their ability to present viral antigen.
8. There is a difference in the distribution and spread of a viral antigen, development of lesions and correlation between presence of viral antigen and lesions.
9. The absence of viral antigens on the surface of equine herpesvirus-1-infected peripheral blood mononuclear cells is a strategy to avoid complement-mediated lysis.
10. Viral Protein Influences Key Cell-signaling Pathway.
11. A viral protein produced by cancer-causing virus influences a key signaling pathway in the immune cells that the virus infects. This stimulates the cells to divide, helping the virus spread through the body.
12. Protection by recombinant viral proteins against a respiratory virulent avian metapneumovirus has been achieved.
13. Viral O-acetylesterases are found in influenza C viruses and Corona-viruses. Viral O-acetylesterases remove cellular receptors from the surface of target cells which destroys the receptor. Recombinant viral O-acetylesterases derived from Sf9 insect cells as chimeric proteins fused to eGFP specifically hydrolyze 9-O-acetylated sialic acids, while that of sialodacryoadenitis virus, a rat coronavirus related to mouse hepatitis virus, is specific for 4-O-acetylated sialic acid. The recombinant esterases were shown to specifically de-O-acetylate sialic acids on glycoconjugates. The recombinant viral proteins can be used to unambiguously identify O-acetylated acids.
Products for Viral Antigens
- Feline Leukemia Virus(1)
- Helicobacter Pylori(3)
- Hepatitis A(14)
- Hepatitis B(10)
- Hepatitis C(74)
- Hepatitis D(1)
- Hepatitis E(5)
- S. Typhi(5)
- Shiga Like Toxin(2)
- West Nile(2)
- Cat.No. 产品名称 Information
- GP26445 Dengue Envelope-2 14 kDa Recombinant Dengue Envelope 2 produced in E
- GP26444 Anhui H7N9 Anhui H7N9 produced in Sf9 Baculovirus cells is a single, glycosylated polypeptide chain containing 330 amino acids (19-339 aa) and having a molecular mass of 36 kDa
- GP26443 SIV GAG SIV GAG Recombinant produced in E
- GP26442 HIV-2 gp160 HIV-2 gp160 produced in E
- GP26441 HIV-1 GAG HIV-1 GAG Recombinant produced in E
- GP26440 HIV-1 CRF HIV-1 CRF Recombinant produced in E
- GP26439 HIV-1 gp41 Subtype-c Recombinant HIV-1 gp41 Subtype-c produced in E
- GP26438 HIV-1 gp41 Subtype-b Recombinant HIV-1 gp41 Subtype-b produced in E
- GP26437 HIV-1 NEF Biotin Recombinant HIV-1 nef Biotin Labeled is a full length protein produced in E
- GP26436 Treponema TP0453 Recombinant Treponema pallidum Outer Membrane Protein TP0453 has a Mw of 26kDa, and was purified from E
- GP26435 Toxoplasma P35 Recombinant Toxoplasma Gondii P35 (GRA8) containing 217 amino acids was purified from E
- GP26434 CMV Pp65, 561 a.a. The E
- GP26433 CMV Pp38 The E
- GP26432 HBsAg adw CHO Recombinant Hepatitis B Surface Antigen Adw subtype, CHO has a Mw of 23kDa, containing 226 amino acids and was purified from CHO cell line
- GP26431 HBe VLP Recombinant hepatitis B Virus-e Virus Like Particle is produced in E
- GP26430 HAVCR2 Mouse HAVCR2 Mouse Recombinant produced in HEK293 cells is a single, glycosylated polypeptide chain (20-193 a
- GP26429 HCV 8th Generation The E
- GP26428 HCV NS3 Genotype-3a Recombinant Hepatitis C Virus NS3 Genotype-3a produced in E
- GP26427 HCV NS3 Genotype-1b C33C Recombinant Hepatitis C Virus NS3 Genotype-1b C33C (40-315 aa) produced in E
- GP26426 Borrelia p30 Borrelia Burgdorferi p30 Recombinant produced in E
- GP26425 Borrelia p28 Borrelia Burgdorferi p28 Recombinant produced in E
- GP26424 CoV-2 Omicron The E
- GP26423 CoV-2 3CL Recombinant Coronavirus 2019 3CL Protease having a Mw of approximately 33
- GP26422 CoV-2 N (329 a.a.) The E
- GP26421 CoV-2 N (127 a.a.) The E
- GP26420 CoV-2 N (196 a.a.) The E
- GP26419 CoV-2 N (201-419) The E
- GP26418 CoV-2 N-Mosaic The E
- GP26417 CoV-2 N (1-419) The E
- GP26416 CoV-2 N (1-419), Biotin TheHEK293 derived recombinant biotinylated protein contains the Coronavirus 2019 CoV-2 Nucleocapsid, Wuhan-Hu-1 strain, amino acids 1-419 fused toHis-Avi tag at C-terminal
- GP26415 CoV-2 N (1-419), HEK The HEK293 derived recombinant protein contains the Coronavirus 2019 CoV-2 Nucleocapsid, Wuhan-Hu-1 strain, amino acids 1-419 fused to His tag at C-terminal having a calculated Mw of 47
- GP26414 CoV-2 Nucleocapsid The E
- GP26413 CoV-2 Spike S1 (200-800) The E
- GP26412 CoV-2 Membrane Env. The E
- GP26411 CoV-2 Envelope (1-75) The E
- GP26410 CoV-2 Spike (318-542) Recombinant Coronavirus 2019 Spike Receptor Binding Domain (318-542 aa) having a Mw of 25
- GP26409 CoV-2-Spike (1-260) The HEK293 derived recombinant protein contains the Coronavirus 2019-Spike N-Terminal Domain, Wuhan-Hu-1 strain, amino acids 1-260 fused to Fc tag at C-terminal
- GP26408 CoV-2 Spike (300-600) The E
- GP26407 CoV-2-Spike (1-1211) The CHO derived recombinant protein contains the Coronavirus 2019-Spike Full-Length protein, Wuhan-Hu-1 strain, amino acids 1-1211 having a Mw of 134 kDa fused to His tag at C-terminal
- GP26406 CoV-2 Spike (1000-1200) The E
- GP26405 CoV-2 Spike (800-1000) The E
- GP26404 CoV-2 Spike E-Mosaic The E
- GP26403 CoV-2 S2, Sf9 The Sf9 derived recombinant protein contains the Coronavirus 2019 CoV-2 Spike Glycoprotein S2, Wuhan-Hu-1 strain, 685-1211 amino acids, having a Mw of 60
- GP26402 CoV-2 S2 The HEK293 derived recombinant protein contains the Novel Coronavirus 2019-nCoV Spike Glycoprotein S2, Wuhan-Hu-1 strain, amino acids 685-1211 fused to Fc tag at C-terminal
- GP26401 CoV-2 S1 (16-685), Biotin TheHEK293 derived Biotinylated recombinant protein contains the Coronavirus 2019 CoV-2 Spike Glycoprotein S1, Wuhan-Hu-1 strain, amino acids 16-685 fused toHis tag & Avi-tag at C-terminal
- GP26400 CoV-2 S1 (16-685), Fc TheHEK293 derived recombinant protein contains the Coronavirus 2019 CoV-2 Spike Glycoprotein S1, Wuhan-Hu-1 strain, amino acids 16-685 fused to Fc tag at C-terminal
- GP26399 CoV-2 S1 (16-685) The recombinant Coronavirus 2019 CoV-2 Spike Glycoprotein S1, Wuhan-Hu-1 strain containing a total of 680 amino acids (16-685) and having a calculated Mw of 76
- GP26398 CoV-2 S1 (319-529) The recombinant Coronavirus 2019-nCoV Spike Glycoprotein-S1 Receptor Binding Domain containing a total of 221 amino acids (319-529) and having a calculated Mw of 24
- GP26397 CoV-2 S1 (319-537) The HEK293 derived recombinant protein contains the Coronavirus 2019 Spike Glycoprotein S1 Receptor Binding Domain [ RBD ], Wuhan-Hu-1 strain, amino acids 319-537, having a Mw of 26
- GP26396 CoV-2-S1 (319-541), Biotin The HEK293 derived Biotinylated recombinant protein contains the Coronavirus 2019 Spike Glycoprotein S1 Receptor Binding Domain [ RBD ], Wuhan-Hu-1 strain, amino acids 319-541 fused to His tag & AVI tag at C-terminaland having a molecular mass of 28