Rationale - disconnect: because in vitro and in vivo binding site conditions are different in terms of physiological substances near the binding site or feedback mechanisms that may affect binding. (Ting book)
20230726ACUC committee,
Imaging protocol, Rob (Takeda ex employee)
FEPPA, & DPA714 both area ready to go at Dana Farber,
TSPO longitudinal (~3w observation, to determine maximal uptake) → main study (202310) → result 202311 → PDE
Labelling imaging
Led by TE
Imaging
20230911(Parra, 2020 #2452)
[NLRP3 PET] 6OHDA rat
IACUC already approved,
Surgery validated, already up & running
Precursor to be synthesized for 11C labeling (old for 18F: stability x) (C not liked, but POC possible) (11c labeling is possible at Dana Farber)
PET study in 202312, : surgery 20231211 → scanning 1(D1 dpa714, D3 FEPPA, D7 DPA714, D14 FEPPA, D21 DPA714) , Scanning 2 (reverse order)

PE2I) → result 202401 (?),
[TSPO PET] AAV aSyn rat
  • To amend Sortwell protocol,
  • To amend MSU contract
  • IACUC approval when? Dec가능tjd
All these need to be completed before 202409 (CS)
2024020820240208: precursor has been shipped,

[18F]DPA714 7 days post surgery confered the greatest signal window.
o
[study1: time course]
Ipsilateral AAV-aSyn and contralateral AAV-EV
  • (The AAV asyn overexpression will ramp up and be maximal 3 weeks after surgery)
  • At each imaging time point 4 satellite animals will be euthanized and brains harvested (2 frozen + 2 formalin fixed) for IHC and ARG work
  • We're not going to do a dynamic scan. We're going to do a 30 min static scan
-(four) image three rats longitudinally, so the same three rats will be imaged at all time points. The additional rat imaged will be killed fixed, for pathology group (also additoial brain fron satellite anial)
-(satellite animal)
20240408The chemistry has been worked out that we have our collaborators at Dana Farber can actually make the C eleven tracer (NLRP3 PET 지칭)

[plan]
6OHDA surgery at (Robbie Robertson) TBOS (or at Dana Farber) → transfer the animals to Dana Farber and they can actually do the image (C11 의 half life 짧아서 tbos 에서 못하고 imaging 는 Dana Farber 에서 해야함)
x days post surgeryx weeks post surgery
surgey4/15/2024
Ship → TBOS arrival4/18/2024all 16) arrived safely
recovery for 1 w
1st imaging4/23/2024scanning the first 5 rats today. 3 of which will be for the longitudinal assessment, the other 2 will be euthanized and brains harvested for IHC121.7
4/30/2024192.7
5/7/2024263.7
5/14/2024334.7
5/21/2024405.7
5/29/2024476.7
6/4/2024547.7
6/11/2024618.7
6/18/2024689.7
6/25/20247510.7
7/2/20248211.7
7/9/20248912.7

[study 2: Tx impact]

rodent: dpa more metabolic activity (DPA with the DE fluoridation with the skull uptake, you can see, you can see that the the skull uptake here which is which is which is a result of DE fluoridation), FEPPA is better, human: vice versa

GOF mouse

20230111
compound[3H]TR06706493
result
Next step-Possible at-Risk in vivoPET experiment in 4-level 6-OHDA rats and NLRP3 GoFmice with in vivo candidates tracer ((for 18F-label).)
-ARG study of patient samples using TR493

6OHDA Rat

Initial (202202)Optimized (202204)Blocking study
comp undTR850 (iv);
0.01mg/kg at 1hr 이건 안 하는 듯
0.01mg/kg at 2hr (n=6)
0.1mg/kg at 4hr (n=6)
0.1mg/kg at 2hr (repeat from first study)(n=5)

다른 in vivo LCMS study 에서는 what dose? 많은 dose 쓰면 안 되나?
6OHDA → (d10)blocker, Tool compound (TR06692993 would be the best compound as a blocker with enough exposure and good permeability & low clearance. Please share estimated brain free conc of TR993 at 5 PO in rats): PO 30mg/kg
→ after 1hr(Cmax), tracer (TR06647850 IV) → 4h after, tissue collection
melisurgeries beginning of April, → dosing will be mid-April. Samples will be collected on 13th Apr (TSD time) → The concentrations of TR850 will be generated next week1 week habituation , → the dosing will be on 25th, July → the samples (plasma and striatum) will be obtained on 1st , August → PK data will be available around the middle of August. @Rolzin, Paul
May I ask to measure the NLRP3 protein level in the striatum again?, because this is the first time study at CRO and we would like to confirm the reproducibility of NLRP3 increase in the LPS model.
The brain surgery might be affected the BBB penetration. As control, sham surgery would be desirable?

After confirming an appropriate regimen of TR850, team will discuss on the protocol for the blocking study of TR850 with CN candidate.
Fold change is similar between vehicle treated and '993 treated animals → significant blocking not observed.
The increase in TR850 concentration at the injection site may be due to the disruption of morphological change of the BBB barrier caused by 6OHDA injection.

29 Jun 2022 2022 年 6 月 29 日 14:11
Untitled Section Page 1 change of the BBB barrier caused by 6OHDA injection
ult(small NLRP3 WB bar-chart inset, kept as evidence) NLRP3 (WB: ↑ 2x at ?mg, x h?)
-Maybe ↑ SB
-Paul: I do worry about changes in nonspecific binding (eg. any tissue morphology changes in the striatum and that what we are seeing is not specific binding (due to increased NLP3 expression).
Blocking study plan:

LPS (systemic) Rat

1st2nd3rd
compTracer (850) dose: (0.1 & 1 mpk
LPS dose: (2 mpk
tissue collection time: 1& 2 h
↓ Tracer (850) dose: (0.1 & 1 mpk → ) 0.01 & 0.1 mpk
↓ LPS dose: (2 mpk → ) 0.5 mpk
↓ tissue collection time: 1& 2 h ) → 2 & 4 h
LPS (ip): 0.5 mpk, 4 days → IV (different tracer) TR06683014 and TR06683015 (iv) , → tissue collection after 1,2h
liThe brain samples in this study were shipped to TSD Paul to check the NLRP3 expression levels. The results of NLRP3 expression will be generated next week.
3Plasma and striatum concentrations of TR06683014 and TR06683015 at 1 & 2 hr of 0.01 mpk in LPS rats was generally comparable with ~10ul...
ult↑ NLRP3, ↑ IL-1b, =THTR06647850: Fold increase at 4 hr of 0.1 mg/kg in LPS rats was observed as well as 6-OHDA rats. However, there was no difference between control LPS rats but no increase was observed in < mg/kg LPS rats. The results of the 2 mg/kg group was reasonable because the final dosing of LPS wasThere was no big difference of Kp...

Uncertain Spans

locationtranscriptionuncertainty
1st imaging schedule, “x weeks post surgey” columninitial value 1.7 next to 4/23/2024The 1.7 weeks figure is calculated from 12 days post-surgery; preserved as-seen.
6OHDA Rat ult rowinline NLRP3 WB bar-chartBar chart with multiple bars (cell numbers not legible) is kept as evidence; the caption “NLRP3 (WB: ↑ 2x at ?mg, x h?)” is preserved.
LPS (systemic) Rat 3rd column tail”There was no big difference of Kp…”Tail of the cell continues beyond the photo; the rest is cropped at the page edge.
20240208 row”[18F]DPA714 7 days post surgery confered the greatest signal window.""confered” preserved as misspelled in original.
Bottom-left “comp und / meli / ult / li / 3” row labelsleftmost row identifiersTruncated in the photo; preserved as-seen.