20240722_183101

row	TSPO	P2X7 receptor	CSF1R
	2022, https://doi.org/10.1101/2022.09.21.22280 194 De novo PD patients vs HC (Rodriguez-Chinchilla, 2020 #2163) Raav-BASED ASYN RAT MODEL (intranigral injection of AAV) → [18F]-DPA714 ↑ in SN, preceding TH loss. DPA-714 signal이 16w 까지 계속 증가하며 이 때 microglial morphology는 reactive 가 predominant!. Correlation between DPA-714 and IBA1 cells: r=0.41 (significant), Correlation between DPA-714 and TH cells: r=0.45 (significant), Correlation between DPA-714 and GFAP cells: only r=0.17 (non-significant). Cf) (Hagens, 2018 #2144) POC of [18F]DPA in MS patients ~~2nd generation~~ [3rd generation] insensitive to TSPO rs6971 polymorphisms ( [18F]GE-180 (=flutriciclamide) (R,S)-[18F]GE-387, [11C]ER176, [11C]CB184, [11C]CB190, [11C]N'-MPB, [18F]LW223 Good review: (Zhou, 2021 #2050)	[SMC] (Lee, 2022 #2005): 18F([1] 5-cyano-N-(4-(4-(2-[¹⁸F]fluoroethyl)piperazin-1-yl)-2-(piperidin-[¹⁸F]1-yl)phenyl)furan-2-carboxamide, Chemistry: = 18F-labeled derivative of CPPC with a longer half-life In vitro studies Cell-free assay, (FRET assay): Binding Affinity: IC50 (phosphorylation extent) of 3.42 nM (comparable to CPPC) 'well plate binding study' Binding confirmed in well plates coated with CSF1R (vs non-coated wells, x7 fold) In vivo studies Model set up: LPS (10 mpk, ip) → ↑ CSF1R in brain (x124, vs control mouse, ELISA). 이 실험에선 tracer 안 사용 PET study: [18F]1 in the LPS mouse → ↑ brain uptake (vs control, SUV from TAC analysis, 몇배인지 숫자무). Blocking study (pet uptake가 낮아서 ex-vivo biodistribution study한 듯): 3군 (control, LPS, LPS+Blocker) : LPS, (hot) tracer, (cold) blocker 모두 in vivo 상태에서 systemic injection함. → 45min 후 mouse culling → 18F]1 level (by what assay? HPLC?): LPS mice 에서 ↑ 78%, which decreased by 22% by a blocker (CPPC)	18F-JNJ-64413739, has initial human data, preclinical data are available online (www.nas.edu). 11C-GSK1482160, has been evaluated in vitro, in vivo in both mice and EAE rat models (Han et al., 2017), have human data presented at conference [108, 110] 11C-GSK1482160 has been characterised in a LPS model of inflammation where V_T was significantly increased upon treatment, with 97% of the increased signal displaced in LPS and homologous block-treated animals [111]. The in vivo selectivity profile for 11C-GSK1482160 is currently lacking heterologous P2X7 blocking data. In vitro response to P2X7-expressing cells and correlation to expression of P2X7 and activated microglia in an ex vivo multiple sclerosis rodent model both increase confidence in selectivity [111,112], but are not in themselves proof of P2X7 binding in vivo. a second generation CSF1R PET in development by J&J : potential that this new ligand is undergoing FiH testing [11C]NCGG401 (Ogata, 2022 #2023) National Center for Geriatrics and Gerontology showed a high potency to inhibit human CSF1R kinase activity (IC50 27.9 nM) by ATP-competitive assay a high binding affinity to human CSF1R - Kd 26.0 nM (by microscale thermophoresis) (HOT) In vivo: (Cold in vivo 는 안 했군!) (baseline:) in three rats, brain radioactivity peaked at 2 min (SUV 1.2), followed by a rapid washout (Figure 2a, 2b). The time activity curves showed the highest activity in the cerebellum and the lowest in the cingulate at 60 min after injection. The peak brain uptake of [11C]NCGG401 appeared to be slightly higher than the reported brain uptake of [11C]BLZ945 (3% ID/g in mice20), although this increased uptake could be due to species differences. However, [11C]NCGG401 was still be a substrate of efflux transporters because the peak brain uptake was increased by ~30% and ~50% after administration of cyclosporine A (25 and 50 mg/kg) and tariquidar (15 mg/kg), respectively (Supplementary figure S4). *blocking : pre-administration of NCGG401 (1.0 mg/kg) starting at 30 min before the tracer injection over 10 min. Pre-administration of NCGG401 did not affect the apparent rate of tracer washout (Figure 2c), not showing SB! (실패! 원인해석: The blocking agents need to be administered well before the bolus injection of the tracer so that receptor occupancy by cold blocking agents is relatively stable.) ARG: The radioactivity was blocked by 10 µM NCGG401 showing decreased radioactivity by 24% (작다!) in the brain tissue samples from rat and 20% in the samples from AD patients, respectively. These findings suggest that [11C]NCGG401 specifically binds to the rat brain and human hippocampus
Link to microglia	nonspecific to migroglia, reactive glial cells. Due to limitations of TSPO-targeted PET, including a lack of cell type specificit	11C-SMW139, currently being evaluated in PD patients (www.clinicaltrialsregister.eu, EudraCT Number: 2018-000405-23, https://www.clinicaltrialsregister.eu/ctr-search/trial/2018-000405-23/FI). It was proposed as potential marker of M1 microglia, however, there is little evidence to support lack of expression of P2X7 on M2 subpopulation, with multiple studies contradicting this hypothesis [267, 268].	The gene encoding the cognate ligand for CSF1R, CSF1, is up-regulated in stage 2 disease-associated microglia (DAM),
limitation	A third issue is that TSPO presence reflects a broader inflammatory state since TSPO is also expressed to a lesser extent on astrocytes and on peripheral immune cells in the brain if the BBB is broken. Fourth, current TSPO tracers bind to both the M1 and M2 phenotypes of activated microglia	Issue with cell-specific expression (expressed peripherally & in microglia, astrocytes, and Schwann cells in the CNS. P2X7 receptor is mainly expressed in microglia cells but its expression level is low in astrocytes and some neurons [20].	(De Lucia, 2016 #1790) Although a report recently suggested CSF1R is expressed and functions in neurons (Luo et al. 2013), we observed that CSF1R-modulatory approaches are specific for microglia, and found no evidence that the receptor is expressed either by neurons or astrocytes, supporting previously reported data (Erblich et al. 2011; Gomez-Nicola et al. 2013; Sasmono et al. 2003).
Link to PD	(Gerhard, 2006 #655) Cross-sectional 11 HC & PD (n=18, all stage, mean H&Y 2.3), : ↑ TSPO signal in SN, BG, cortex, ant & post cingulate gyrus, brainstem: But microglial activation did not correlate with clinical severity or putamen 18F]-dopa uptake Correlation analysis (Pearson statistics) revealed a significant negative correlation between [11C](R)-PK11195 binding potential values in the anterior and posterior cingulate and clinical duration of symptoms (r = 0.559, P = 0.012 and r = 0.636, P = 0.005 respectively) as well as in the thalamus (r = 0.526, P = 0.025). BP values in other regions did not correlate significantly	{Van Weehaeghe, 2019 #1793} 2^ND, a small (twofold) increase in the P2X7R gene in RNA extracted from the substantia nigra in PD patients [44].	TO BE EXPLORED!
	Figure 2 (bar-chart panels, kept as evidence in `body_r04_c01.jpg`): Caption: Fig. 2. Mean binding potential values with standard deviation (SD) for the patients at baseline and the healthy volunteers. Significant increases are indicated: P < 0.05; P < 0.01; sn = substantia nigra. Increases indicated as () did not survive testing for multiple comparisons. (positively or negatively) with either clinical parameters or 18 putaminal [F]-dopa signal
	Longitudinal cohort: PD (N=8), no longitudinal change over 2 y, despite change in UPDRS (19→ 25) & putaminal [18F]-dopa Ki values (6.7% ANNUAL DECLINE)
	Cristian's paper: Varnas 2019 (PBR28, PD), Nettis 2020 (PBR28, sc IFN-a CHALLENGE hv), If old paper, 당시엔 NLRP3 assay 없었음. → 피검사결과 없 PET 다시 해야함 (그 사이에 변경 가능성 유) NEW PAPER 있는지 https://doi.org/10.1016/j.apsb.2020.08.006 → 있다면, r-ecall previously TSPO-scanned patients for blood NLRP3 measurement. 뒤져보자.
	(Ghadery, 2017 #1642) "Koshimori 2015 의 extension" stratified by rs6971 polymorphism, MABs) (14 PD patients and 11 age-matched HC (HC)) and 27 (HABs) (16 PD patients and 11 age-matched HC) [18F]-FEPPA → Results: no difference in PD vs HC (Ghadery 2020): [18F]-FEPPA: HAB vs MAB 구분 결과 없는 듯 (Koshimori, 2015 #1773) this is just a part of (Ghadery, 2017 #1642)	{Van Weehaeghe, 2019 #1793} 2^ND recent study in a rat model of neuroinflammation using the 18F analogue [18F]JNJ64413739 showed that P2X7R is involved in early microglial activation. The highest signal was observed 2-3 days after LPS injection, after which this effect disappeared. Moreover, increased uptake of [18F]JNJ64413739 was shown to correspond with increased Iba1 staining, a microglial marker, indicating that P2X7R radioligands are probably able to visualize microglial activation [23].
	(Ouchi, 2005 #656) [11C](R)-PK11195 (300MBq) Cross-sectional: 10 early (drug-naïve) PD patients vs 10 age-matched HC, ↑ (midbrain) TSPO signal in midbrain (didn't look at cortex), Table 2 (kept as evidence in `body_r05_c01.jpg`, lower portion clipped): Levels of Binding Potential (b/c) for [11C]CFT and [11C]PK11195. Mean (SD) with Group / Tracer / [11C]CFT / [11C]PK11195 columns broken into Striatum (Anterior / Caudate / Putamen) and Cortex (Ventral / Frontal / Dorsal / Thalamus) sub-columns; row data values are too small to transcribe with confidence.

Uncertain Spans

location	transcription	uncertainty
`Link to microglia / TSPO cell tail`	reads `including a lack of cell type specificit` with the trailing `y` clipped at the cell edge in this capture.	clipped at cell boundary; not reconstructed.
`Link to PD / TSPO / In vivo PET note in NCGG401 cell`	the cell-text characters surrounding the bar-chart figure are partly clipped by the chart crop; the surrounding paragraph is reconstructed from the visible portions in `body_r03_c01.jpg` and `body_r04_c01.jpg`.	partial clip; preserved as visible.
`Link to PD / Ouchi 2005 Table 2 row values`	Table 2 of Ouchi 2005 is visible at the bottom of `body_r05_c01.jpg` but row data values are too small for confident transcription; only the header structure is recorded.	left as evidence only.