Abstract
Noninvasive imaging atherosclerotic (AS) plaque is of great importance for early diagnosis. Recently, CD93 in MΦ was linked to atherosclerosis development. Herein, we have investigated whether CD93 in MΦ is a potential novel target for atherosclerotic plaque imaging. CD93hi and CD93lo MΦ were prepared with or without LPS stimulation, before biological activity was evaluated. A rat AS model was produced with left carotid artery clamped. Whole-body/ex vivo phosphor autoradiography of the artery and biodistribution were investigated after incorporation of 3 H-2-DG into CD93hi and CD93lo MΦ or after 125 I-α-CD93 (125 I-anti-CD93mAb) injection. The plaque tissue was subjected to CD93/CD68 immunofluorescence/immunohistochemistry staining. CD93hi and CD93lo MΦ cells were successfully prepared without significant effect on bioactivity after incorporative labelled with 3 H-2-DG. The AS model was successfully established. Biodistribution studies showed that adoptive transfer of 3 H-2-DG-CD93hi MΦ or 125 I- α-CD93 injection resulted in accumulation of radioactivity within the atherosclerotic plaque in the clamped left carotid artery. T/NT (target/non-target, left/right carotid artery) ratio was higher in the 3 H-2-DG-CD93hi MΦ adoptive transfer group than in the 3 H-2-DG-CD93lo MΦ group (p < .05). Plaque radioactivity in the 125 I-α-CD93 injection group was significantly higher than in the 125 I-IgG control group (p < .01). The higher radioactivity accumulated in the clamped left carotid artery was confirmed by phosphor autoradiography. More importantly, CD93/CD68 double-positive MΦ accumulated at the atherosclerotic plaque in 3 H-2-DG-CD93hi MΦ adoptive transfer group, which correlated with plaque radioactivity (r = .99, p < .01). In summary, both adoptive-transferred 3 H-2-DG-labelled CD93hi MΦ and 125 I-α-CD93 injection specifically targeted CD93 in atherosclerotic plaque. CD93 is a potential target in atherosclerotic plaque imaging.