Table 2.
Typical Features of Immunoglobulin Super Family Therapeutic Agents
| Feature | IgG Antibody | TCR mimic | TCR |
|---|---|---|---|
| Isoforms | Multiple | Multiple | Alpha/beta or gamma/delta |
| Structure | Homodimer | Homodimer | Heterodimer |
| Mass (Daltons) | 150,000 | 150,000 | 40,000/ 80,000 |
| Affinity (typical; native) | High: 0.1–10nM | High: 0.1–10nM | Low: 0.1–10uM |
| Target antigens | All accessible molecules | Peptide/MHC | Peptide/MHC; Lipid, peptide, metabolite/CD1, MR1, HLA-E; Non peptidic-phospho-antigen/BNT3A1 |
| HLA restriction | No | Yes | Yes and No |
| Soluble forms (native) | Yes | Yes | No |
| Membrane bound (native) | No | No | Yes |
| Typical Platforms: | |||
| ● Native | Yes | Yes | Yes |
| ● Fc modified | Yes | Yes | N/A |
| ● Truncated forms | Various | Various | Yes |
| ● Bispecific forms | Yes | Yes | Yes |
| ● ADC* | Yes | Yes | No |
| ● RIC* | Yes | Yes | No |
| ● CAR* or T-cell | Yes | Yes | Yes |
| Half-life (soluble forms) | Long (weeks) | Long (weeks) | Short (hours) |
| Specificity | High | Variable | Variable |
| Marketed | Multiple | No | One (as of 2022) |
| Current clinical Indications | Diverse & many | Cancer | Cancer |
| Discovery/development | Simple | Complex | Complex |