Expression of IDO in human and murine TDLNs. (A) Sentinel (first
draining) LN from patients with breast carcinoma (left, ×100) and
malignant melanoma (right, ×400), showing an abnormal infiltration
of IDO+ cells (red chromogen). (B) Kaplan-Meier
survival plot of 40 patients with malignant melanoma, stratified into those with
an abnormal accumulation of IDO+ cells in the sentinel LN
(+IDO), versus a normal (negative) pattern. (C)
Expression of IDO in murine B16F10 melanoma. Left: Draining inguinal LN from a
mouse with a B16F10 tumor, day 12, stained for IDO (red, ×100).
Middle: Contralateral inguinal LN from the same animal as at left, stained for
IDO (red, ×100). Right: High-power view of IDO+ cells
shown in the left panel (×1,000). Controls for staining (anti-IDO
antibody neutralized with the immunizing peptide) showed a negative pattern
similar to that seen in the contralateral LN (not shown). (D)
Draining and contralateral LNs from a mouse with B78H1–GM-CSF tumor,
day 12, stained for IDO (red, both ×200).