C05G5.5 Antibody

Definition and Nomenclature

• C05 Antibody: A broadly neutralizing monoclonal antibody targeting the receptor-binding site of influenza A hemagglutinin (HA), with activity across H1, H2, H3, H9, and H12 subtypes .

• V5-Tag Antibody: A short peptide tag (GKPIPNPLLGLDST) used for protein detection and purification, detected via immunoprecipitation, Western blot, or ELISA .

• CRMP-5 Antibody: An autoantibody linked to paraneoplastic neurological syndromes, detected via immunoblot or immunofluorescence assays .

Possible interpretations of "C05G5.5" include:

• A gene identifier (e.g., C. elegans gene nomenclature).

• A proprietary or experimental antibody code.

• A misreference to C05 or other antibodies.

C05 Antibody

• Mechanism: Dominated by a 24-residue HCDR3 loop, which penetrates the HA receptor-binding site. Avidity (IgG vs. Fab) enhances neutralization despite low Fab affinity (Kd ~10 µM) .

• Efficacy:

  • In Vitro: Neutralizes H1N1, H3N2, H9, and H12 strains.

  • In Vivo: Protects mice from lethal challenge at doses as low as 3 mg/kg .

• Cross-Reactivity: Binds conserved HA stem regions, enabling heterosubtypic neutralization .

V5-Tag Antibody

• Utility: Enables recombinant protein purification via affinity chromatography or detection in WB/ELISA .

• Applications: Widely used in molecular biology for protein expression validation.

CRMP-5 Antibody

• Clinical Relevance: Linked to small-cell lung cancer and paraneoplastic chorea. Detected via immunoblot or IFA .

• Diagnostic Challenges: Requires antigen-specific assays due to cross-reactivity risks .

Challenges and Future Directions

• Nomenclature Ambiguity: "C05G5.5" may represent a gene, uncharacterized antibody, or typographical error. Clarification is critical for targeted research.

• Complementarity-Determining Regions (CDRs): Long CDRs (e.g., C05’s HCDR3) enable targeting of conserved epitopes but may pose structural challenges .

• Immunogenicity: Humanized antibodies (e.g., trastuzumab, bevacizumab) reduce immunogenicity but require careful backmutation to retain affinity .