Histopathologic Methods for Mouse Oxazolone Induced Ear Delayed Type Hypersensitivity

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Oxazolone Induced Ear Delayed Type Hypersensitivity (Mouse) Histology/Histopathology Methods

Ear Width

The ear thickness was measured at 4 sites starting at the base (thickest part if orientation is unclear) and progressing toward the tip (thinnest area), with approximately equally spaced measurements taken proximal to the mid point (toward head), one taken distal to the midpoint, and one at the midpoint. Measure #1 nearest to the base, #2 between midpoint and the base measure, #3 is the mid point, and #4 is distal (toward tip, approximately). This parameter documents edematous thickening and greater widths generally correlate with greater inflammation.

Dermal Inflammation Score

0 = Normal, no inflammation
0.5 = Very minimal, focal 1-2 inflammatory cells/25×25 square µm area
1 = Minimal, diffuse or multifocal minimal infiltrate, 1-2 inflammatory cells/25×25 square µm area
2 = Mild, diffuse or multifocal mild infiltrate, 3-5 inflammatory cells/25×25 square µm area
3 = Moderate, diffuse mild (3-5) infiltrate of inflammatory cells plus area of more severe infiltrate 6-12 inflammatory cells/25×25 square µm area
4 = Marked, diffuse marked infiltrate of inflammatory cells, 9-12 inflammatory cells/25×25 square µm area
5 = Severe, diffuse severe infiltrate of inflammatory cells, >12 inflammatory cells/25×25 µm area

Epidermal Inflammation and Hyperplasia Score

0 = Normal, no inflammation
0.5 = Very minimal inflammation (no obvious epidermal abscess) or focal epidermal hyperplasia generally less than 30 µm thick
1 = Minimal, 1-2 epidermal accumulations of inflammatory cells (less than 600µm total abscess length) or scattered single cell accumulations or multifocal or diffuse minimal epidermal hyperplasia generally less than 30 µm
2 = Mild, 3-4 epidermal accumulations of inflammatory cells (600-800 µm total abscess length) or mild multifocal or diffuse hyperplasia (skin thickness is 10-40 µm)
3 = Moderate, 5-6 epidermal accumulations of inflammatory cells (800-1100 µm total abscess length) or moderate diffuse hyperplasia (skin thickness is 40-70 µm)
4 = Marked, 7-8 epidermal accumulations of inflammatory cells (1100-1400 µm total abscess length), or marked diffuse hyperplasia (skin thickness is 60-90 µm)
5 = Severe, >8 epidermal accumulations of inflammatory cells (greater than 1400 µm total abscess length) or severe diffuse hyperplasia (skin thickness is >90 µm)

Summed Inflammation Score

The dermal and epidermal inflammation scores are summed.

General Inflammation