AGP20 Antibody

ADG20 (Adintrevimab): Anti-COVID-19 Monoclonal Antibody

ADG20 (adintrevimab) is a SARS-CoV-2 neutralizing monoclonal antibody developed by Adagio Therapeutics. While not named "AGP20," its nomenclature and clinical profile suggest a potential nomenclature overlap:

Key Features

• Target: SARS-CoV-2 spike protein (broadly neutralizing against pre-Omicron variants, including Delta) .

• Mechanism: Binds the receptor-binding domain (RBD) to block viral entry.

• Clinical Efficacy:

  Indication	Risk Reduction vs. Placebo	Population
  Pre-exposure prophylaxis	71%	High-risk individuals
  Post-exposure prophylaxis	75%	Household contacts
  Early COVID-19 treatment	77% (hospitalization/death)	≤3 days post-symptom onset

• Structural Classification:
  ADG20 belongs to Class 1 neutralizing antibodies (per Barnes et al. ), characterized by:

  • VH3-53 heavy chain usage

  • Short CDRH3 loops (9–12 amino acids)

  • ACE2-binding site overlap, requiring "up" RBD conformation for epitope access .

gp20: Sperm Surface Glycoprotein with Immunogenic Epitopes

A glycoprotein designated gp20 shares structural homology with CD52 and exhibits O-linked oligosaccharide epitopes recognized by immunoglobulins:

Epitope Analysis

• Structure: GPI-anchored sialylglycoprotein with O-glycosylation at unique CD52 glycoforms .

• Functional Role: Implicated in sperm maturation and capacitation.

• Antigenic Profile:

  • Anti-gp20 antibodies target carbohydrate epitopes (not peptide backbone or GPI anchor).

  • Epitope specificity differs from CAMPATH antibodies (e.g., equatorial sperm head localization vs. pan-surface binding) .

AGP-Targeting Antibodies in Plant and Mammalian Systems

Unrelated to "AGP20," several arabinogalactan protein (AGP)-specific antibodies exist:

Arabinogalactan-Protein (AGP) Antibodies