SPP1 and heart failure: Recombinant osteopontin (OPN) and CD163 were administered to assess their therapeutic effect in Cd163<sup>-</sup> <sup>/</sup> <sup>-</sup> mice.<h4>Results</h4>Circulating soluble CD163 levels were markedly elevated in patients with ICM-induced heart failure compared with individuals without heart failure (median difference 34.5 ng/mL, IQR 13.6-54.6 ng/mL, p = .002) and showed a positive correlation with the extent of systolic dysfunction and left ventricular (LV) dilation.