PORB Antibody
Description
Introduction to PORB Antibody
The PORB antibody (e.g., PACO52266) is a polyclonal antibody raised in rabbits against recombinant PorB protein from Neisseria meningitidis serogroup B. PorB, a β-barrel transmembrane protein, facilitates ion transport across bacterial membranes and modulates host immune responses . Its structural and functional diversity across bacterial strains makes it a focal point for studies on microbial adaptation and therapeutic targeting .
Antibody Characteristics
Key specifications of the PORB Polyclonal Antibody (PACO52266) include:
This antibody exhibits high specificity for PorB’s extracellular loops, which are critical for ion selectivity and immune evasion .
Functional Roles in Bacterial Pathogenesis
PorB contributes to bacterial survival through:
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Antibiotic Resistance: Alters outer membrane permeability to reduce drug uptake .
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Immune Evasion: Binds host complement regulators (e.g., factor H) to inhibit opsonization .
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TLR Activation: Acts as a Toll-like receptor (TLR) 1/2 agonist, triggering pro-inflammatory cytokine production .
Studies show PorB variants from N. gonorrhoeae (Gc) and N. meningitidis (Nm) share 70–78% sequence identity, enabling cross-reactive antibody responses .
Mechanistic Insights into Immune Response Modulation
The PORB antibody has been instrumental in elucidating PorB’s adjuvant properties:
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Antigen Trafficking: Enhances antigen deposition on follicular dendritic cells (FDCs) by 2.5-fold compared to CpG adjuvants, promoting B-cell affinity maturation .
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Cellular Immunity: Drives Th1-biased responses (high IgG2a/IgG1 ratios) when delivered via viral replicon particles (VRPs), unlike alum-based Th2 polarization .
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Bactericidal Activity: Anti-PorB monoclonal antibodies demonstrate in vitro killing of Gc (e.g., 80% killing of strain FA1090 at 10 µg/mL) .
Vaccine Development
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4CMenB Vaccine: Elicits cross-reactive PorB antibodies that reduce Gc colonization in murine models .
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Mucosal Immunity: Intranasal delivery of PorB-containing outer membrane vesicles (OMVs) induces mucosal IgA (mean titer >1:160) and serum bactericidal activity .
Antibody Engineering
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Human monoclonal antibodies (e.g., 01C05, 02G22) targeting conserved PorB epitopes show cross-species neutralizing activity .
Challenges and Future Directions
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Antigenic Diversity: PorB’s hypervariable loops necessitate multivalent vaccine formulations .
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Antibody Cross-Reactivity: Low IgG/IgA titers against heterologous PorB variants (<1:100) highlight immunodominance challenges .
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Adjuvant Optimization: Combining PorB with nanoparticle delivery systems may enhance cellular uptake and durability of immune responses .
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- Studies using reconstituted Pchlide-POR-NADPH complexes have shown fluorescence maxima at 77 K. (PMID: 25659137)
- Overexpression of PORA in porB-1 porC-1 seedlings and adult plants has been shown to restore light-dependent chlorophyll production, thylakoid stacking, and photomorphogenesis in response to illumination. (PMID: 20012672)
- Research into the import of PORA and PORB into plastids of intact seedlings has revealed a variety of import pathways that differ in their substrate, cell, tissue, and organ specificities. (PMID: 15842619)
