Mixed-affinity binding in humans with 18-kDa translocator protein ligands

TY - JOUR

T1 - Mixed-affinity binding in humans with 18-kDa translocator protein ligands

AU - Owen, David R J

AU - Gunn, Roger N

AU - Rabiner, Eugenii

AU - Bennacef, Idriss

AU - Fujita, Masahiro

AU - Kreisl, William C

AU - Innis, Robert B

AU - Pike, Victor W

AU - Reynolds, Richard

AU - Matthews, Paul M

AU - Parker, Christine A

PY - 2011

Y1 - 2011

N2 - 11C-PBR28 PET can detect the 18-kDa translocator protein (TSPO) expressed within macrophages. However, quantitative evaluation of the signal in brain tissue from donors with multiple sclerosis (MS) shows that PBR28 binds the TSPO with high affinity (binding affinity [Ki], ∼4 nM), low affinity (Ki, ∼200 nM), or mixed affinity (2 sites with Ki, ∼4 nM and ∼300 nM). Our study tested whether similar binding behavior could be detected in brain tissue from donors with no history of neurologic disease, with TSPO-binding PET ligands other than 11C-PBR28, for TSPO present in peripheral blood, and with human brain PET data acquired in vivo with 11C-PBR28.

AB - 11C-PBR28 PET can detect the 18-kDa translocator protein (TSPO) expressed within macrophages. However, quantitative evaluation of the signal in brain tissue from donors with multiple sclerosis (MS) shows that PBR28 binds the TSPO with high affinity (binding affinity [Ki], ∼4 nM), low affinity (Ki, ∼200 nM), or mixed affinity (2 sites with Ki, ∼4 nM and ∼300 nM). Our study tested whether similar binding behavior could be detected in brain tissue from donors with no history of neurologic disease, with TSPO-binding PET ligands other than 11C-PBR28, for TSPO present in peripheral blood, and with human brain PET data acquired in vivo with 11C-PBR28.

U2 - 10.2967/jnumed.110.079459

DO - 10.2967/jnumed.110.079459

M3 - Article

C2 - 21149489

SN - 1535-5667

VL - 52

SP - 24

EP - 32

JO - Journal of Nuclear Medicine

JF - Journal of Nuclear Medicine

IS - 1

ER -