Table 2.

Histopathologic grading scale of TNBS-E-induced colitis

Grade of colitis	Microscopic findings
0	No damage
I	Mild mocosal and/or submucosal inflammatory infiltrate and edema: punctuate mucosal erosions often associated with capillary proliferation, muscularis mucosa intact
II	Grade I changes involving 50% of the specimen
III	Prominent inflammatory infiltrate and edema frequently with deeper areas of ulceration extending through the muscularis mucosa into the submucosa, rare inflammatory cells invading the muscularis propria but without muscle necrosis
IV	Grade III changes involving 50% of the specimen
V	Extensive ulceration with coagulative necrosis bordered inferiorly by numerous neutrophils and fewer mononuclear cells, necrosis extends deeply into the muscularis propria
VI	Grade V changes involving 50% of the specimen