Structural Modeling: Triplet-Axis Assembly Assessment
Authors/Creators
Description
Abstract
CCR5 antagonism, PD-L1 modulation, and broadly neutralizing antibodies (bN-
Abs) represent complementary axes in immune modulation and viral control. To eval-
uate whether these axes could physically co-assemble as a structural triplet, curated
Protein Data Bank (PDB) structures for CCR5 (4MBS), PD-L1 (8GAD), and a PD-
L1-targeted nanobody (5DXW) were analyzed using UCSF ChimeraX (daily build,
2025-10-13, macOS). Manual alignment and visual inspection identified no sterically
permissible three-body geometry, suggesting that a direct CCR5–PD-L1–bNAb com-
plex is structurally improbable. These observations support the interpretation that
synergy across these axes occurs indirectly through regulatory and signaling interac-
tions rather than physical co-binding.
Full report and figures are included in the attached PDF.
Files
IMG_7452.png
Additional details
Software
- Repository URL
- https://firegatebiotech.org/fg-001%3A-immunotherapy
References
- 1. Tan Q., et al. Structure of the CCR5 chemokine receptor bound to maraviroc. Science. 2013;341(6152):1387–1390. (PDB: 4MBS)
- 2. Zak K.M., et al. Structure of the complex of human programmed death ligand 1 and the PD-1 receptor. PNAS. 2015;112(52):E6505–E6514. (PDB: 8GAD)
- 3. Ma L., et al. A PD-L1-targeting nanobody that enhances T-cell activation and anti- tumor immunity. Nature Communications. 2018;9:5364. (PDB: 5DXW)
- 4. Pettersen E.F., et al. UCSF ChimeraX: Structure visualization for researchers, educa- tors, and developers. Protein Science. 2021;30(1):70–78.