Abstract: Objective To establish a method for detecting circulating brain microvascular endothelial cells (cBMECs), a novel
biomarker of blood-brain barrier (BBB) injury. Methods Blood samples were collected from 33 patients with AIDS encephalitis
and 13 healthy subjects for detection of cBMECs, cECs and EPCs using magnetic affinity isolation and immune identification
technology. Results The numbers of cBMECs, cECs and EPCs were significantly higher in the AIDS patients than in the control
subjects (t=4.298, P<0.01; t=4.886, P<0.01; t=4.889, P<0.01). An significant association was also noted between HIV load and
cBMEC number (r=0.928, P<0.01). Conclusion We have successfully established a method for detecting peripheral blood
cBMECs, which can be of important value in non-invasive assessment of BBB injury.