Evaluation of colitis
The severity of colitis was evaluated by continuously weight change,
colon length, disease activity score, macroscopic damage score,
histological score and colonic cytokines levels following an established
protocol 27.
For assessing disease activity score, two investigators scored the
results by body weight loss, stool consistency and rectal bleeding in a
double-blinded manner. The scores were quantified as follows: body
weight loss on a scale of 0–5 for <5%, 5–10%, 10–15%,
15–20%, 20–25%, >25%, respectively; stool consistency
on a scale of 0–2 for normal, soft, liquid, respectively; and rectal
bleeding on a scale of 0–1 for absent, present, respectively.
For assessing macroscopic damage score, two investigators scored the
results by presence of strictures and hypertrophic zones, adhesion areas
and intraluminal hemorrhage in a double-blinded manner. The scores were
quantified as follows: presence of strictures and hypertrophic zones on
a scale of 0–3 for absent, one stricture, two strictures, more than two
strictures, respectively; mucus on a scale of 0–1 for absent, present,
respectively; adhesion areas between the colon and other intra-abdominal
organs on a scale of 0–3 for absent, one adhesion area, two adhesion
areas, more than two adhesion areas, respectively; intraluminal
hemorrhage on a scale of 0–1 for absent, present, respectively;
erythema on a scale of 0–2 for absent, presence of a crimsoned area
< 1 cm2, presence of a crimsoned area
> 1 cm2 , respectively; and ulcerations
and necrotic areas on a scale of 0–2 for absent presence of a necrotic
area < 1 cm2, presence of a necrotic area
> 1 cm2, respectively.
For assessing colonic histology score, two investigators scored the
results by epithelial surface damage, the loss of crypts and
inflammatory infiltration in a double-blinded manner. The scores were
quantified as follows: crypt damage on a scale of 0–4 for no damage,
basal one-third damaged, basal two-thirds damaged, only surface
epithelium intact, and entire crypt epithelium lost, respectively; depth
of injury on a scale of 0–3 for no, mucosal, mucosal and submucosal,
and transmural injury, respectively; and inflammatory infiltration on a
scale of 0–3 for no, slight, moderate, and severe inflammation,
respectively.