Table 2.
The primary stimuli and receptors generating antibody responses. APC, antigen presenting cell; MHC-II, Major histocompatibility-II; LPS, lipopolysaccharide; TLR, Toll-like receptor.
| Stimulus Class | Examples | Receptors | Antibodies Produced | Antibody Isotypes | Recall Memory Responses |
|---|---|---|---|---|---|
| T-dependent | APC-processed protein peptides with MHC-II | T cell receptor | Antigen-specific | IgM, IgG, IgA, IgE | Yes |
| T-independent type 1 (TI-1) | Innate | Polyclonal (not stimulus-specific) | IgM | No | |
| LPS (mice) | - TLR-4 | ||||
| CpG | - TLR-9 | ||||
| Poly-IC (dsRNA) | - TLR-3 | ||||
| R848 | - TLR7/8 | ||||
| T-independent type 2 (TI-2) | Capsular polysaccharides | B cell receptor | Antigen-specific | IgM, IgG, IgA | +/− |