Rat brain Endothelial Cell (RBEC) Monolayer
The rat brain endothelial cell (RBEC) monolayer assay is an excellent in vitro test system to model the Blood-Brain-Barrier (BBB) and study the brain penetration of compounds by evaluating their vectorial transport.
General Features
- suitable for studying the blood-brain-barrier penetration of compounds:
"permeability studies" - in vitro assay
- toxicity test: 5 concentrations of TA in triplicate
Specific Features
- brain endothelial cell co-culture system with pericytes and astrocytes
- Mdr1a transporter specific setups are available: Mdr1a inhibitor assessment (Drug-drug Interaction) and Mdr1a substrate assessment
- substrates and inhibitors are harmonized with SOLVO's rat brain microdialysis services
Check out SOLVO's comprehensive blood-brain-barrier transporter testing solutions
SOLVO is developing its Bcrp1-specific rat brain endothelial cell (RBEC) monolayer assay. For further information, please, contact us
Studies available
- Permeability studies
- Mdr1a substrate assessment studies
- Mdr1a inhibitor assessment (DDI) studies
Setups available
SOLVO also offers two setups for the above studies, which differ in the amount of information derived and costs.| 1. Basic setup | - Studies at one concentration |
| 2. Extended setup | - Studies at several concentrations, more controls |
Study parameters can be customized to suite your needs. The following tables summarize some adjustable parameters.
Optional parameters for RBEC monolayer studies
| Parameter | Options | Effect on Price |
| Unidirectional | A-B or B-A | depends on nr of wells |
| Nr. of replicates | triplicates or more | depends on nr of wells |
| TA concentration | no limitations | no effect on price |
| Nr of TA concentrations | no limitations | depends on nr of wells |
| Sink conditions | + 1% BSA in receptor compartment | no effect on price |
| Non-specific binding | wells without cells | depends on nr of wells |
| Nr. of samples taken | time points and compartments | depends on nr of LC/MS/MS analytical samples |
1. Permeability studies (uni- and bi-directional)
| Basic | Extended | ||
| assay conditions | concentration TA | 1 | 3 |
| samples (minutes) | R: 0, 15, 30, 60 | R: 0, 15, 30, 60 | |
| R:receptor D:donor | D: 0, 60 | D: 0, 60 | |
| Nr of replicates | 3 | 3 | |
| Direction | BA or AB/BA | BA or AB/BA | |
| controls | non-specific binding | wells without cells | wells without cells |
| permeability | Sodium fluorescein | Sodium fluorescein | |
| Evans blue albumin | Evans blue albumin | ||
| functionality | quinidine, AB, BA | quinidine, AB, BA | |
| monolayer confluency | TEER | TEER | |
| toxicity | 5 concentrations of TA | 5 concentrations of TA |
2. Mdr1a substrate assessment studies
| Basic | Extended | ||
| assay conditions | concentration TA | 1 | 2 |
| samples (minutes) | R: 0, 60 | R: 0, 60 | |
| R:receptor D:donor | D: 0, 60 | D: 0, 60 | |
| specific inhibitor for Mdr1a | PSC833 | PSC833 | |
| Nr of replicates | 3 | 3 | |
| Direction | AB/BA | AB/BA | |
| controls | non-specific binding | wells without cells | wells without cells |
| permeability | Sodium fluorescein | Sodium fluorescein | |
| Evans blue albumin | Evans blue albumin | ||
| functionality | quinidine, AB, BA | quinidine, AB, BA | |
| specific inhibitor for Mdr1a | PSC833 | PSC833 | |
| monolayer confluency | TEER | TEER | |
| toxicity | 5 concentrations of TA | 5 concentrations of TA |
3. Mdr1a inhibitor assessment (Drug-drug Interaction) studies
| Basic | Extended | ||
| assay conditions | concentration TA | 1 | 5 |
| samples (minutes) | R: 0, 60 | R: 0, 60 | |
| R:receptor D:donor | D: 0, 60 | D: 0, 60 | |
| probe substrate | 3H-quinidine | 3H-quinidine | |
| Nr of replicates | 3 | 3 | |
| Direction | AB/BA | AB/BA | |
| controls | non-specific binding | wells without cells | wells without cells |
| permeability | Sodium fluorescein | Sodium fluorescein | |
| Evans blue albumin | Evans blue albumin | ||
| functionality | quinidine, AB, BA | quinidine, AB, BA | |
| toxicity | 5 concentrations of TA | 5 concentrations of TA | |
| specific inhibitor for Mdr1a | PSC833 | PSC833 | |
| monolayer confluency | TEER | TEER |
Validation data
Moreover, the contribution of the Mdr1a transporter to the active absorption/efflux processes can be determined by the application of selective substrate (quinidine) and inhibitor (PSC833) (Figure 2.).
Scientific background
SOLVO's RBEC (Rat Brain Endothelial Cell) monolayer assay applies primary rat brain microvascular endothelial cells isolated from two-week old rats, co-cultured with rat pericytes and rat astrocytes (triple co-culture system).
Endothelial cells are cultured on the upper side of a semipermeable porous filter, having pericytes on the backside and astrocytes in the bottom of the wells of the culture plate (Figure 1.). Brain endothelial cells in contact with pericytes and astrocytic factors form a tight monolayer which separates two solute compartments, above and below the cell layer, that corresponds to the capillary lumen (apical side) and the brain interstitium (basolateral side), respectively.
Under appropriate cell culture conditions, RBEC monolayers maintain the main characteristics of the cerebral endothelium in vivo such as expression of von Willebrand factor, high activity and inducibility by astrocytes of the alkaline phosphatase and gamma glutamyl transpeptidase activity.
| A) | B) | |
 |  |
ENDOTHELIAL |
| PERICYTES | ||
| ASTROCYTES | ||
| Figure 1. In vivo (A) and in vitro (B) representation of the Blood-brain-barrier | ||