|
1 | 1 | # Overview |
2 | 2 |
|
3 | | -Per-clonotype structural developability analysis for antibody candidates. Consumes per-clonotype PDB files from the [3D Structure Prediction](https://github.com/platforma-open/3d-structure-prediction) block upstream and emits per-clonotype liability calls, surface developability metrics, and a composite developability cost that downstream blocks (Lead Selection) can rank candidates on. |
4 | | - |
5 | | -Sequence-only liability scanners (see our sister [Antibody Sequence Liabilities](https://github.com/platforma-open/antibody-sequence-liabilities) block) flag every regex match without knowing whether the chemically reactive atom is solvent-exposed. This block adds 3D context: filters motif hits by relative solvent-accessible surface area (rSASA), weights each hit by region (CDR3 > CDR1/2 > FR), gates low-confidence residues using the per-residue predicted error emitted by ImmuneBuilder, and adds structural-only signals (surface hydrophobicity / charge patches, free-Cys state, CDR-H3 compactness). |
6 | | - |
7 | | -Surface metrics follow [Raybould 2019 TAP](https://doi.org/10.1073/pnas.1810576116) verbatim for paired Fv (surface hydrophobicity, positive-charge patches, negative-charge patches, Fv charge symmetry) and [Gordon 2025 TNP](https://github.com/oxpig/TNP) for VHH (same metrics with type-restricted charge patches plus CDR-H3 compactness). SASA is computed with [FreeSASA](https://freesasa.github.io/) under the Shrake-Rupley algorithm at a 1.4 Å probe radius, the configuration both calibration cohorts use. Threshold bands are pinned to the literature cohorts: cohortSize 242 for Fv (Raybould 2019 Table 2), cohortSize 36 for VHH (Gordon 2025 `assign_flag()`). |
8 | | - |
9 | | -Outputs are per-clonotype scalar `PColumn`s keyed on `pl7.app/vdj/scClonotypeKey`. The composite cost `structuralDevelopabilityScore` aggregates motif risk (`fixabilityWeight × regionWeight × exposure`), per-metric threshold-flag bumps, and cysteine penalties. Two categorical risks ride alongside: `structuralDevelopabilityRisk` (None / Low / Medium / High) and `structuralIntegrityRisk` (None / Present, for broken or missing canonical disulfides, exposed extra cysteines, and structural-tier motifs). Per-metric raw values + None/Medium/High threshold flags are exported, with `<metric>LowConfidenceResidueFraction` columns letting users discount metrics dominated by low-confidence regions of the prediction. |
10 | | - |
11 | | -## UI |
12 | | - |
13 | | -The Main page renders a per-clonotype results table with default-visible columns (developability cost, risk levels, per-metric flags, cysteine counts) and a "Columns" toggle that reveals raw metric values and low-confidence fractions. Double-clicking a row opens a Mol\*-based 3D structure viewer for that clonotype with confidence-coloured per-residue rendering. Five distribution pages (surface hydrophobicity, positive-charge patches, negative-charge patches, mode-specific Fv-charge-symmetry / CDR-H3 compactness, and developability cost) render the Raybould / Gordon threshold lines so each candidate's standing against the literature thresholds is visible without leaving the chart. A run-summary alert fires when more than 25% of clonotypes have at least one confidence-gated motif. |
14 | | - |
15 | | -## Honest scope |
16 | | - |
17 | | -Flags reflect the **predicted apo conformation**. CDR-H3 in particular can rearrange on antigen binding, so a residue buried in the apo prediction may be exposed in the bound state. The value-prop is "removes apo-state-buried false positives", not "removes all false positives". The per-metric low-confidence-residue fraction lets users discount metrics dominated by uncertain regions of the prediction. |
18 | | - |
19 | | -## References |
20 | | - |
21 | | -> Raybould MIJ, Marks C, Krawczyk K, Taddese B, Nowak J, Lewis AP, Bujotzek A, Shi J, Deane CM. *Five computational developability guidelines for therapeutic antibody profiling.* PNAS 116(10), 4025–4030 (2019). [https://doi.org/10.1073/pnas.1810576116](https://doi.org/10.1073/pnas.1810576116) |
22 | | -
|
23 | | -> Gordon GL, Raybould MIJ, Deane CM. *TAP 2.0: a refined platform for assessing the developability of nanobodies (in silico).* bioRxiv (2025). [https://doi.org/10.1101/2025.08.11.669635](https://doi.org/10.1101/2025.08.11.669635) |
| 3 | +Per-clonotype structural developability analysis for antibody candidates. |
| 4 | +Consumes per-clonotype PDB files from the [3D Structure |
| 5 | +Prediction](https://github.com/platforma-open/3d-structure-prediction) block |
| 6 | +upstream and emits per-clonotype liability calls, surface developability |
| 7 | +metrics, and a composite developability cost that downstream blocks (Lead |
| 8 | +Selection) can rank candidates on. |
| 9 | + |
| 10 | +Sequence-only liability scanners (see our sister [Antibody Sequence |
| 11 | +Liabilities](https://github.com/platforma-open/antibody-sequence-liabilities) |
| 12 | +block) flag every regex match without knowing whether the chemically reactive |
| 13 | +atom is solvent-exposed. This block adds 3D context: filters motif hits by |
| 14 | +relative solvent-accessible surface area (rSASA), weights each hit by region |
| 15 | +(CDR3 > CDR1/2 > FR), gates low-confidence residues using the per-residue |
| 16 | +predicted error emitted by ImmuneBuilder, and adds structural-only signals |
| 17 | +(surface hydrophobicity / charge patches, free-Cys state, CDR-H3 compactness). |
| 18 | + |
| 19 | +Surface metrics follow [Raybould 2019 |
| 20 | +TAP](https://doi.org/10.1073/pnas.1810576116) verbatim for paired Fv (surface |
| 21 | +hydrophobicity, positive-charge patches, negative-charge patches, Fv charge |
| 22 | +symmetry) and [Gordon 2025 TNP](https://github.com/oxpig/TNP) for VHH (same |
| 23 | +metrics with type-restricted charge patches plus CDR-H3 compactness). SASA is |
| 24 | +computed with [FreeSASA](https://freesasa.github.io/) under the Shrake-Rupley |
| 25 | +algorithm at a 1.4 Å probe radius, the configuration both calibration cohorts |
| 26 | +use. Threshold bands are pinned to the literature cohorts: cohortSize 242 for |
| 27 | +Fv (Raybould 2019 Table 2), cohortSize 36 for VHH (Gordon 2025 |
| 28 | +`assign_flag()`). |
| 29 | + |
| 30 | +> Raybould MIJ, Marks C, Krawczyk K, Taddese B, Nowak J, Lewis AP, Bujotzek A, |
| 31 | +> Shi J, Deane CM. _Five computational developability guidelines for |
| 32 | +> therapeutic antibody profiling._ PNAS 116(10), 4025–4030 (2019). |
| 33 | +> [https://doi.org/10.1073/pnas.1810576116](https://doi.org/10.1073/pnas.1810576116) |
| 34 | +
|
| 35 | +> Gordon GL, Raybould MIJ, Deane CM. _TAP 2.0: a refined platform for assessing |
| 36 | +> the developability of nanobodies (in silico)._ bioRxiv (2025). |
| 37 | +> [https://doi.org/10.1101/2025.08.11.669635](https://doi.org/10.1101/2025.08.11.669635) |
24 | 38 |
|
25 | 39 | SASA computation uses [FreeSASA](https://freesasa.github.io/). Please cite: |
26 | 40 |
|
27 | | -> Mitternacht S. *FreeSASA: An open source C library for solvent accessible surface area calculations.* F1000Research, 5:189 (2016). [https://doi.org/10.12688/f1000research.7931.1](https://doi.org/10.12688/f1000research.7931.1) |
| 41 | +> Mitternacht S. _FreeSASA: An open source C library for solvent accessible |
| 42 | +> surface area calculations._ F1000Research, 5:189 (2016). |
| 43 | +> [https://doi.org/10.12688/f1000research.7931.1](https://doi.org/10.12688/f1000research.7931.1) |
0 commit comments