Hi @marvizon
Some labs do intra-DRG injections, but it’s a delicate technique that I myself have not mastered. But if you just want to hit DRG, it’s not necessary, unless you really just want a particular DRG (say, left L5 DRG).
Intrathecal works very well, but it is dependent on titer and serotype and promoter.
Many labs have found that AAV9 in the 10^13 vg/ml range (10 ul typical dose) works very well intrathecally. I’ve done this myself. Which DRGs do you want to hit?
Here is the original reference that I used for my own work:
Recently, this paper found that you can use AAV9 intraplantar and get good retrograde transduction. The key is < P5 animals. I haven’t done this myself although I want.
https://www.cell.com/cell-reports/pdf/S2211-1247(18)30624-7.pdf
I’d do the intrathecal route. You need high titer AAV9 though. I’ve had the best success with AAV from Penn vector core. Addgene distributes their stocks now and makes their vectors. It looks like Addgene carries Cre-dependent inhibitory (hm4di) DREADD in AAV9 but not the activating ones. So you may need a custom prep. Make sure it’s 10^13 vg/ml. I haven’t had success with less. See the reference above too. The issue here though is the hSyn promoter. It works, but not amazingly in DRG. CAG is better.
See this discussion
Good luck. Let us know how it goes.