Table 1.
Definition of categories and general criteria in histomorphological scores for intestinal inflammation in mouse models
| Category | Criterion | Definition | Score Value1 |
|---|---|---|---|
| I, Inflammatory cell infiltrate | Severity | Leukocyte density of lamina propria area infiltrated in evaluated hpf: | |
| Minimal: <10% | 1 | ||
| Mild: 10-25%; scattered neutrophils | 2 | ||
| Moderate: 26-50% | 3 | ||
| Marked: >51%; dense infiltrate | 4 | ||
| Extent | Expansion of leukocyte infiltration: | ||
| Mucosal | 1 | ||
| Mucosal and submucosal | 2 | ||
| Mucosal, submucosal and transmural | 3 | ||
| II, Epithelial changes2 | Hyperplasia | Increase in epithelial cell numbers in longitudinal crypts relative to baseline epithelial cell numbers per crypt; visible as crypt elongation: | |
| Minimal: <25% | 1 | ||
| Mild: 25-35% | 2 or 3 | ||
| Moderate: 36-50%; mitoses in middle/upper third of crypt epithelium, distant from crypt base | 3 or 4 | ||
| Marked: >51%; mitoses in upper third of crypt epithelium, distant from crypt base | 4 or 5 | ||
| Goblet cell loss | Reduction of goblet cell numbers relative to baseline goblet cell numbers per crypt: | ||
| Minimal: <20% | 1 or 2 | ||
| Mild: 21-35% | 2 or 3 | ||
| Moderate: 36-50% | 3 or 4 | ||
| Marked: >50% | 4 | ||
| Cryptitis | Neutrophils between crypt epithelial cells | 2 or 3 | |
| Crypt abscesses | Neutrophils in crypt lumen | 3 to 5 | |
| Erosion | Loss of surface epithelium | 1 to 4 | |
| III, Mucosal architecture2 | Ulceration | Epithelial defect reaching beyond muscularis mucosae | 3 to 5 |
| Granulation tissue | Connective tissue repair with new capillaries, surrounded by spindle-shaped fibroblasts, myofibroblasts, macrophages, neutrophils and mononuclear cells as well as cell debris; pseudopolyps: villiformous, hypertrophied areas projecting into the lumen | 4 or 5 | |
| Irregular crypts | Non-parallel crypts, variable crypt diameters, bifurcation and branched crypts | 4 or 5 | |
| Crypt loss | Mucosa devoid of crypts | 4 or 5 | |
| Villous blunting | Mild: villous-to-crypt-length ratio of 2:1 to 3:1 | 1 to 3 | |
| Moderate: villous-to-crypt-length ratio of 1:1 to 2:1 | 2 to 4 | ||
| Villous atrophy | 3 to 5 |
1
Values given for single criteria are not additive but represent the final score value that include all relevant criteria;
2
From well-oriented samples/biopsies with longitudinally cut crypts only, at least 5 comparable crypts.