In addition, we also measured the binding ΔH 0 s between Gx-psDiMan and wild type DC-SIGN by isothermal titration calorimetry (ITC). These were performed by titrating concentrated DC-SIGN (30 µM) into concentrated Gx-psDiMan solution (e.g., 300 nM for x = 5, and 100 nM for x = 13) in the ITC cell to measure binding induced heat changes (see SI, section 6) and the results were summarized in Table . It should be noted that ITC cannot provide accurate measurement of the binding ΔG 0 (hence Kd) directly for very strong interactions (e.g., sub-to low-nM Kds), although its measurement of ΔH 0 values is accurate.