CaiJ,YuanH,WangQ,etal.HMGB1-DrivenInflammationandIn-timalHyperplasiaAfterArterialInjuryInvolvesCell-SpecificActionsMediatedby TLR4[J].Arterioscler ThrombVasc Biol,2015 ,35(12): 2579-2593. [10] LeiC,WuB,CaoT,etal.Activationof thehigh-mobilitygroupbox multiple sites of metastasis or sites of potential toxicity. To address this need, in vivo imaging of both adaptive and innate immune cell populations has emerged as a tool to quantify spatial leukocyte accumulation in tumors non-invasively. Here we review recent progress in the translational development of probes for in vivo leukocyte imaging, focusing on complementary