Assessment of traumatic brain injury by increased ⁶⁴Cu uptake on ⁶⁴CuCl₂ PET/CT

Copper is a nutritional trace element required for cell proliferation and wound repair. Methods: To explore increased copper uptake as a biomarker for noninvasive assessment of traumatic brain injury (TBI), experimental TBI in C57BL/6 mice was induced by controlled cortical impact, and ⁶⁴Cu uptake in the injured cortex was assessed with ⁶⁴CuCl2 PET/CT. Results: At 24 h after intravenous injection of the tracer, uptake was significantly higher in the injured cortex of TBI mice (1.15 ± 0.53 percentage injected dose per gram of tissue [%ID/g]) than in the uninjured cortex of mice without TBI (0.53 ± 0.07 %ID/g, P 5 0.027) or the cortex of mice that received an intracortical injection of zymosan A (0.62 ± 0.22 %ID/g, P 5 0.025). Furthermore, uptake in the traumatized cortex of untreated TBI mice (1.15 ± 0.53 %ID/g) did not significantly differ from that in minocycline-treated TBI mice (0.93 ± 0.30 %ID/g, P 5 0.33). Conclusion: Overall, the data suggest that increased ⁶⁴Cu uptake in traumatized brain tissues holds potential as a new biomarker for noninvasive assessment of TBI with ⁶⁴CuCl2 PET/CT.