Correction: Apo-Form Selective Inhibition of IDO for Tumor Immunotherapy.

Abstract

Liu, W., Y. Zou, K. Li, H. Zhong, L. Yu, S. Ge, Y. Lai, X. Dong, Q. Xu, and W. Guo. 2022. Apo-form selective inhibition of IDO for tumor immunotherapy. J. Immunol. 209: 180-191. Supplemental Table I did not originally contain the Protein Data Bank (PDB) code for the x-ray crystal structure analyzed in the article. The coordinates of PDB ID 8I7L were released after publication on February 15, 2023. Supplemental Table I has been corrected online. As this structure is marginally different from the one originally analyzed in the article, the first paragraph of the Results section headed "Distinct bonding networks from those of BMS-986205 contributed to the potency of B37" was amended to reflect the updated resolution limit and root-mean-square deviation of this structure. The corrected paragraph is shown below. Having identified B37 as a compound with a superior biochemical profile, we crystallized the hIDO1-B37 complex and refined its structure to a resolution of 2.80 Å (Fig. 3A, Supplemental Table I) to understand the structural basis of binding. Strong electron density associated with B37 and adjacent water molecules was evident in the binding pocket. B37 binding did not significantly alter the overall structure of IDO1 (root-mean-square deviation of 0.671) compared to holo-IDO1 (PDB code: 6AZU) (17). The major structural rearrangement introduced by B37 binding was a shift in the region between G261 and Q271, an event previously observed as a result of binding of the substrate tryptophan or its analogs (29, 30). In particular, the heme-coordinating residue A264 was the most significantly perturbed (root-mean-square deviation measured at Cα = 3.6) upon B37 binding. B37 and heme shared a cavity similar to that of BMS-978587 and BMS-986205 inside IDO1 (Fig. 3B-I), confirming the hypothesis that B37 is a heme-competitive IDO1 inhibitor. Unlike the nearly planar heme molecule, B37 and its halogenated phenyl moiety extend deeply into the "A" pocket located in the distal heme site (7, 11). The corrections have been made in the online version of the article, which now differs from the print version as originally published.