CSHL Computational Cell Biology
Islet AssessmentJuly 2012
Allan J. RopskiUniversity of Illinois at ChicagoDepartment of Surgery
Islets of Langerhans•Islet Potency Index
▫FDA requirement for use as a biological drug▫Sterility, identity, and purity are established
•Reliably predict transplant outcomes▫Glucose-stimulated insulin secretion; β-cell specific▫In-vivo streptozotocin treated mice; Potency Index▫UIC-MS islet assays▫Phase III human clinical trials*; 52-week follow-up
•Microfluidic optimization▫Ca2+; Mitochondrial Potential; Insulin release▫High-throughput assays
Human Islet Cell Composition• 6 isolations• 32 sampled islets
• Rangesα-cells 28 – 75%β-cells 10 – 65%δ-cells 1 – 22%
Assessment of Human Pancreatic Islet Architecture and Composition by Laser Scanning Confocal MicroscopyJournal of Histochemistry & Cytochemistry; Volume 53(9): 1087–1097, 2005Marcela Brissova, Michael J. Fowler, Wendell E. Nicholson, Anita Chu, Boaz Hirshberg, David M. Harlan, and Alvin C. Powers
N
Glycolysis
ATP
insulin granules
Insulin secretion Glucose
pyruvate
Mitochondria
β-Cell
K+
K+ K+
K+
K+K+
K+
K+
K+
K+
Ca2+
K+
Ca2+Ca2+
Ca2+ Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Zn+
Zn+
Zn+
Zn+Zn+
Zn+
Zn+Zn+
KATP-dependent depolarization
Phase I Phase II
Basal
3 15
Basal
18
1 2
3
4
Phase I Phase II Oscillation
Time (min)
Cal
cium
co
ncen
tratio
n
VDCC dependent calcium influx
Glucose-stimulated insulin release
Basal
Time (min)
Mito
chon
dria
l pot
entia
ls
High glucose
Mitochondrial hypopolarization
A
B
C
N
Glycolysis
ATP
insulin granules
Insulin secretion Glucose
pyruvate
Mitochondria
β-Cell
K+
K+ K+
K+
K+K+
K+
K+
K+
K+
Ca2+
K+
Ca2+Ca2+
Ca2+ Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Zn+
Zn+
Zn+
Zn+Zn+
Zn+
Zn+Zn+
KATP-dependent depolarization
Phase I Phase II
Basal
3 15
Basal
18
1 2
3
4
Phase I Phase II Oscillation
Time (min)
Cal
cium
co
ncen
tratio
n
N
Glycolysis
ATP
insulin granules
Insulin secretion Glucose
pyruvate
Mitochondria
β-Cell
K+
K+ K+
K+
K+K+
K+
K+
K+
K+
Ca2+
K+
Ca2+Ca2+
Ca2+ Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Zn+
Zn+
Zn+
Zn+Zn+
Zn+
Zn+Zn+
KATP-dependent depolarization
N
Glycolysis
ATP
insulin granules
Insulin secretion Glucose
pyruvate
Mitochondria
β-Cell
K+
K+ K+
K+
K+K+
K+
K+
K+
K+
Ca2+
K+
Ca2+Ca2+
Ca2+ Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Ca2+
Zn+
Zn+
Zn+
Zn+Zn+
Zn+
Zn+Zn+
KATP-dependent depolarization
Phase I Phase II
Basal
3 15
Basal
18
1 2
3
4
Phase I Phase II
Basal
3 15
Basal
18
11 22
33
44
Phase I Phase II Oscillation
Time (min)
Cal
cium
co
ncen
tratio
n
Phase I Phase II Oscillation
Time (min)
Cal
cium
co
ncen
tratio
n
VDCC dependent calcium influx
Glucose-stimulated insulin release
Basal
Time (min)
Mito
chon
dria
l pot
entia
ls
High glucose
Mitochondrial hypopolarization
A
B
C
Microfluidic System
