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Analytical Technologies

Genome scale analyses include

  • Single cell and Single nuclei RNAseq on cell lines and organoids

  • Bulk RNAseq

  • Bulk and single nuclei ATACseq

  • Proteomics

Many cell types are found in cerebral organoids made from DO mouse ES cell lines

Interneuron

Fibroblasts

Choroid Plexus

Glutamatergic Neuron

Radial Glia

Mesenchyme

Epithelial 1

Epithelial 2

Microglia

Oligodendrocyte

  DO.1

  DO.2

AJ

WSB

B6

NOD

CAST

Plate based assays include

  • high content analysis  (PE Opera)

  • RTCA impedance assays (ACEAbio)

  • microelectrode array (Axion Maestro)

  • Fl, Lum, hTRF etc. (PE Envision)

Astrocyte swelling kinetics, RTCA assay. 

Cardiotoxicity Screen 

 

We often develop custom assays for our projects but for a recent project involving genetics of tyrosine kinase inhibitor induced cardiotoxicity we also built our own instrumentation. We needed to conduct beating assays for over 700K wells of  cardiomyocytes derived from over 200 ESC lines. No commercially available instrument or assay met the throughput and cost constraints of the project so we designed and built a custom imager to meet our needs.

 

  • Fully automated high throughput beating cell imager

  • Using three instruments, our current screening capability is 10K wells per day, scalable to over 100K wells per day

  • Scans a 384 well plate in 20 minutes, capturing 20 seconds of beating per well

  • Real-time analysis of image data

  • Completely non-invasive and label-free assay

  • Uses conventional low-cost plasticware

  • Can measure beating in very small regions of the well

  • Uses mouse or human ES/IPS cell lines "off the shelf" without modification or purification, i.e., does not require purified cardiomyocytes

  •  

The video below shows a day 9 embryoid body in a single well of a 384 well plate. The motion is digitized by the imager, depicted as black dots in the panel on the right. The analysis software analyzes the motion and automatically places up to four ROI, (small red circles) at points of optimal beating.

 

Brightfield
Digitized

Only the motion inside an ROI is quantified and graphed as shown below. This graph represents beating for ROI #1 in the video above. Each beat consists of two peaks, one for contraction and one for relaxation. A built-in peakfinding routine then catalogs the beats to calculate the beat-to-beat cycle time. The mean and coefficient of variation for beat score and beat cycle are also automatically calculated.

Contractile properties of cardiomyocytes are reflected in the Beat Scores (Y-axis). Arrhythmic responses result in altered mean and CV for beat cycle times. Contractile and arrhythmic activity are measured simultaneously.

 

Embroid bodies exhibit a high degree of variability and heterogeneity of cells and the location and size of cardiomyocyte patches are unpredictable. In our assay, very small beating patches are scored for beating, and any cells/activity outside of the ROI is ignored by the assay. This assay does not require synchronized beating across the entirety of the well surface. In fact, wells with multiple independent beating clusters can serve as in-well replicates.

Cisapride: lengthening beat cycle and fibrillation-like beating with increasing dose

Blebbistatin: inhibition of  contractility but not rhythmicity

Sunitinib: effect on contractility is resolved from effect on beat cycle, and shows different potencies in different genetic backgrounds