| APC | Antigen-presenting cell |
| DLBCL | Diffuse large B-cell lymphoma |
| EIEC | Enteroinvasive Escherichia coli |
| FeLV | Feline leukemia virus |
| FIV | Feline immunodeficiency virus |
| FMT | Fecal microbiota transplant |
| GALT | Gut-associated lymphoid tissue |
| IBD | Inflammatory bowel disease |
| IgH+ | Immunoglobulin heavy |
| ILFs | Isolated lymphoid follicles |
| SCIL | Small-cell GI lymphoma |
| SFB | Segmented filamentous bacteria |
| TCRγ+ | T-cell receptor |
| Treg | Regulatory T cells |
| Th17 | Helper T lymphocytes |
| WHO | World Health Organisation |
| WSAVA | World Small Animal Veterinary Association |