Abstract: Compositions and methods are disclosed for assessing macrophage involvement in the inflammation of one or more joints of a subject. In certain aspects, the disclosed method includes the steps of administering to the subject a composition comprising a mannosylated dextran construct with an imaging moiety conjugated thereto; acquiring one or more planar images of a first joint of the subject; defining a region of interest (ROI) comprising the first joint; defining a joint specific reference region (RR); determining a MARTAD value of the joint by assessing the ratio of average pixel intensity of the ROI to the average pixel intensity of the RR; and comparing the MARTAD of the first joint to a normal MARTAD value for a corresponding joint, and wherein macrophage involvement is indicated by a joint specific MARTAD value that exceeds the normal MARTAD value by a predetermined threshold.

Abstract: The present application relates to compositions and methods for imaging and/or detecting tumors. In certain embodiments, the imaging and/or detection is targeted to tumor associated macrophages. In some embodiments, a mannosylated dextran construct is used to target and/or detect tumor associated macrophages. In some embodiments, the tumor may be one or more visceral tumors. In some embodiments, the detected and/or targeted tumor may be one or more metastatic tumors.