3rd Generation TSPO

[18F]GE-180 (=flutriciclamide)(R,S)-[18F]GE-387[18F]LW223[18F]FEBMP(Singh 2022 #211): ER176, NEBIFQUINIDE, PBR316, CB251 (skull uptake), BS224, FETEM, FTPQ, Fluorovinpocetine[11C]ER176[11C]CB184[11C]CB190[11C]N-MPB
in vitro [18F]GE-180 has already been approved for human use and has undergone favorable first-in-man studies.
NHP However, Chaney et al. indicated that [11C]DPA-713 PET reflects microglial activation with higher accuracy and sensitivity compared to [18F]GE-180 in a mouse model of stroke (53). Ji et al. reported that [18F]FEBMP (200) yielded a higher contrast to neuroinflammation than [11C]PK11195 in PS19 tauopathy mouse model due to its higher glial-TSPO selectivity (Figures 1F, G) (57, 58). {Ramakrishnan, 2021 #2101} healthy rats and NHPs favourable kinetics (ie brain uptake) XXXX
Rodent LPS model James et al. found that the detection of microglial activation by using [18F]GE180 was more sensitive than that by using [18F]PBR06 (94).

Dickens et al.198 demonstrated that [18F]23 could identify sites of activated microglia in both gray and white matter in a LPS-induced model. (Zhang 2021)

López-Picón et al. showed that [18F]GE-180 signal reached plateaus at an early stage, while the Ab load detected by [11C]PIB was still increasing in APP23 mice (90).
HC (Zanotti-Fregonara et al. 2018, PMID 29348317) HC, low brain uptake (VT of 18F-GE180 was about 20 times smaller than that of 11C-PBR28)
patients {Fan, 2016 #2121} FIH
Increased levels of [18F]GE-180 uptake indicative of microglial activation have been reported in patients with AD (Vettermann et al. 2021, PMID 34073557), semantic dementia, MCI, and four-repeat tauopathy compared to non-demented controls, HC (88–91).
. AD (Vettermann et al. 2021, PMID 34073557): no difference vs HC
Zhang 2021에 200) AD rat
Human-brain-ARG
Human-brain-homogKi? {MacAskill, 2021 #2115} human brain homog, sup fig5G, Ki 0.6 nM (~0.4 nM for HABs and ~0.9 nM for LABs)
Human-brain-homog [binding affinity] {Ramakrishnan, 2021 #2101} (human cortical brain tissue memb suspension, 5.48 ± 0.68 nM (n = 7) for HABs and 9.83 ± 1.28 nM (n = 7) for LABs {MacAskill, 2021 #2115} human brain homog, fig2, not affected by rs6971 polymorphism ((LAB/HAB)=1), 근데 sup fig5G 에는 좀 다른데? v{Tiwari, 2015 #2110} ratio (LAB/HAB): ~1.1 (good)
(fig4), 그림에서 SB 좀 적어보이는데?
Kd: 못 찾음
Human-other {Cumming, 2018 #2126} 2nd Ki against [3H]PK11195 binding, human platelets:
2.5 nM (HAB) 38 nM (LAB) GE Investigator's Brochure)
{MacAskill, 2021 #2115} Vt: fig3. SB 괜찮아보임. Suv: Suppl fig9, 28.7% displacement
binding affinity (Ki, nmol/L) {Chau, 2015 #2122} Rat heart: 0.59 nM
Human (colonic cell membranes): 9.2 nM
binding affinity (Ki, nmol/L) {Qiao, 2019 #2114} 36.3 ± 6.9 (human embryonic kidney cell lines) {Tiwari, 2014 #2111} rat brain homog: 6.6 ± 0.7
lipophilicity (logD)
ratio (LAB/HAB): in vivo {Qiao, 2019 #2114} (human embryonic kidney cell lines) 1.3,
{Ramakrishnan, 2021 #2101} (human cortical brain tissue memb suspension, 1.8
1 to 1.4 (In vivo VT ratio for MAB/HAB) (Zhang 2021, 2nd) {Tiwari, 2014 #2111} rat brain homog: 3.43
ratio (LAB/HAB): human -(Feeney et al. 2016, PMID 27349244) HC: (MAB=HAB).
- 1.4 ((Vettermann et al. 2021, PMID 34073557) HC+Pts (but MAB=HAB)
selectivity {Ji, 2021 #2112} mouse brain, [18F]FEBMP (200) yielded a higher contrast to neuroinflammation than [11C]PK11195 in PS19 tauopathy mouse model due to its higher glial-TSPO selectivity (요약그림 in Zhou 2021).
TSPO in cerebral …

Uncertain Spans

locationtranscriptionuncertainty
HC / [18F]GE-180 cellZanotti-Fregonara et al. 2018, PMID 29348317author surname diacritics not crisp at this zoom; PMID is legible.
selectivity / [18F]FEBMP cell요약그림 in Zhou 2021Korean fragment is small and partly compressed.
last rowTSPO in cerebral …row clipped at bottom edge of photo.