Millicell Organotypic Insert From Millipore

Question: What combines the advantage of the brain 3D structure and function in vivo with the precision of the controlled environment and drug application in vitro?
Answer: Brain organotypic culture.

But how to sustain viable slices of such a delicate organ like brain? Here come the very handy Millicell organotypic inserts, designed especially for that purpose. The most important part, providing high viability of brain organotypic explants, is the Biopore translucent membrane with 0.4 um pore size consisting of PTFE (polytetrafluoroethene - teflon) and enabling excellent oxygen and nutrient delivery to the explant.

I am using these inserts on an everyday basis to culture Hypothalamo-Neurohypophysial (HNS) explants, which are even more finicky then regular (e.g. hippocampal) explants because of their larger thickness of ~ 600-700 um. The cells of the HNS explant have excellent survival, but the trick here is to keep the medium level just right (not to low – explant will dry out; not to high – explant will “drown”). The Millipore organotypic inserts are ideal for this purpose. The access to the medium, control of its level and exchange are very easy.

The Millipore organotypic inserts have also other useful features. They have a high wall decreasing the possibility of contamination during handling. They can be placed in either multi-well plates or individual Petri dishes on built-in stands enabling the medium to have access to the tissue from underneath. The Biopore PTFE membrane is so great in sustaining cell viability that for some custom design projects, I am trimming the insert and saving the membrane to fit to special handmade devices. Again, the survival of explants is very good. The company also claims that this membrane is particularly good for immunofluorescent staining applications and gives little background, although I have never had a chance to check that in practice. Since my explants are rather thick, I am fixing them in the insert and then prepare thinner slices for the immunofluorescent staining.

One critique I have is that it comes in only one size, thus the versatility of applications is reduced. Nevertheless, I have been more than pleased with the quality of Millipore’s organotypic inserts. I recommend them to anyone who wants to study brain functions without the hassle of the rest of the body attached to it.