CD80 and neuroblastoma: In contrast, CD80 expression was significantly down-regulated (MFI: 83.0 ± 18.2 vs 43.7 ± 5.1, p < 0.01) while CD86 expression was not changed in NB patients (MFI: 137.3 ± 18.4 vs 153.6 ± 13.1, p = 0.51).