Anti-RBC antibody characteristics and AMIS induction
| Antibody . | Isotype . | Reactivity . | RBC clearance* . | Antigen modulation† . | AMIS . |
|---|---|---|---|---|---|
| 4B7 | IgG1 | HEL | — | No | Yes |
| de4B7 | IgG1 (deglycosylated) | HEL | −‡ | No‡ | Yes |
| 6D7 | IgG1 | HEL | Unknown§ | Unknown | Yes |
| de6D7 | IgG1 (deglycosylated) | HEL | Unknown§ | Unknown | Yes |
| MIMA 29 | IgG2a | Duffy | +++ | Yes | Yes |
| deMIMA 29 | IgG2a (deglycosylated) | Duffy | ++ | Unknown | Yes (partial) |
| CBC-512 | IgG1 | Duffy | +++ | Unknown | Yes |
| deCBC-512 | IgG1 (deglycosylated) | Duffy | — | Unknown | Yes |
| Antibody . | Isotype . | Reactivity . | RBC clearance* . | Antigen modulation† . | AMIS . |
|---|---|---|---|---|---|
| 4B7 | IgG1 | HEL | — | No | Yes |
| de4B7 | IgG1 (deglycosylated) | HEL | −‡ | No‡ | Yes |
| 6D7 | IgG1 | HEL | Unknown§ | Unknown | Yes |
| de6D7 | IgG1 (deglycosylated) | HEL | Unknown§ | Unknown | Yes |
| MIMA 29 | IgG2a | Duffy | +++ | Yes | Yes |
| deMIMA 29 | IgG2a (deglycosylated) | Duffy | ++ | Unknown | Yes (partial) |
| CBC-512 | IgG1 | Duffy | +++ | Unknown | Yes |
| deCBC-512 | IgG1 (deglycosylated) | Duffy | — | Unknown | Yes |
RBC clearance determined by the percentage of cells remaining 2 hours after injection. +++, <50%; ++, <75%; –, >90%.
Antigen modulation (also known as antigen loss) is a process by which an erythrocyte antigen becomes weakened or undetectable subsequent to antibody binding. The data for antigen modulation are based on previously published data by others.8,13
We presume that de4B7 does not induce RBC clearance or antigen modulation because the wild-type 4B7 does not.
Although we did not test RBC clearance by 6D7, all monoclonal and polyclonal anti-HEL antibodies tested thus far have not induced RBC clearance.12