Abstract
The ability to consistently and reliably assess the total number and the size distribution of isolated pancreatic islet cells from a small sample is of crucial relevance for the adequate characterization of islet cell preparations used for research or transplantation purposes. Here, data from a large number of isolations were used to establish a continuous probability density function describing the size distribution of human pancreatic islets. This function was then used to generate a polymeric microsphere mixture with a composition resembling those of isolated islets, which, in turn, was used to quantitatively assess the accuracy, reliability, and operator-dependent variability of the currently utilized manual standard procedure of quantification of islet cell preparation. Furthermore, on the basis of the best fit probability density function, which corresponds to a Weibull distribution, a slightly modified scale of islet equivalent number (IEQ) conversion factors is proposed that incorporates the size distribution of islets and accounts for the decreasing probability of finding larger islets within each size group. Compared to the current calculation method, these factors introduce a 4-8% downward correction of the total IEQ estimate, but they reflect a statistically more accurate contribution of differently sized islets.
| Original language | English |
|---|---|
| Pages (from-to) | 1223-1235 |
| Number of pages | 13 |
| Journal | Cell Transplantation |
| Volume | 18 |
| Issue number | 10-11 |
| DOIs | |
| State | Published - Dec 1 2009 |
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Keywords
- Frequency distribution
- Islet isolation
- Islets of langerhans
- Probability density function
- Type 1 diabetes
- Weibull distribution
ASJC Scopus subject areas
- Cell Biology
- Transplantation
- Biomedical Engineering
Cite this
Quantitative assessment of islet cell products : Estimating the accuracy of the existing protocol and accounting for islet size distribution. / Buchwald, Peter; Wang, Xiaojing; Khan, Aisha; Bernal, Andres; Fraker, Christopher; Inverardi, Luca A; Ricordi, Camillo.
In: Cell Transplantation, Vol. 18, No. 10-11, 01.12.2009, p. 1223-1235.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Quantitative assessment of islet cell products
T2 - Estimating the accuracy of the existing protocol and accounting for islet size distribution
AU - Buchwald, Peter
AU - Wang, Xiaojing
AU - Khan, Aisha
AU - Bernal, Andres
AU - Fraker, Christopher
AU - Inverardi, Luca A
AU - Ricordi, Camillo
PY - 2009/12/1
Y1 - 2009/12/1
N2 - The ability to consistently and reliably assess the total number and the size distribution of isolated pancreatic islet cells from a small sample is of crucial relevance for the adequate characterization of islet cell preparations used for research or transplantation purposes. Here, data from a large number of isolations were used to establish a continuous probability density function describing the size distribution of human pancreatic islets. This function was then used to generate a polymeric microsphere mixture with a composition resembling those of isolated islets, which, in turn, was used to quantitatively assess the accuracy, reliability, and operator-dependent variability of the currently utilized manual standard procedure of quantification of islet cell preparation. Furthermore, on the basis of the best fit probability density function, which corresponds to a Weibull distribution, a slightly modified scale of islet equivalent number (IEQ) conversion factors is proposed that incorporates the size distribution of islets and accounts for the decreasing probability of finding larger islets within each size group. Compared to the current calculation method, these factors introduce a 4-8% downward correction of the total IEQ estimate, but they reflect a statistically more accurate contribution of differently sized islets.
AB - The ability to consistently and reliably assess the total number and the size distribution of isolated pancreatic islet cells from a small sample is of crucial relevance for the adequate characterization of islet cell preparations used for research or transplantation purposes. Here, data from a large number of isolations were used to establish a continuous probability density function describing the size distribution of human pancreatic islets. This function was then used to generate a polymeric microsphere mixture with a composition resembling those of isolated islets, which, in turn, was used to quantitatively assess the accuracy, reliability, and operator-dependent variability of the currently utilized manual standard procedure of quantification of islet cell preparation. Furthermore, on the basis of the best fit probability density function, which corresponds to a Weibull distribution, a slightly modified scale of islet equivalent number (IEQ) conversion factors is proposed that incorporates the size distribution of islets and accounts for the decreasing probability of finding larger islets within each size group. Compared to the current calculation method, these factors introduce a 4-8% downward correction of the total IEQ estimate, but they reflect a statistically more accurate contribution of differently sized islets.
KW - Frequency distribution
KW - Islet isolation
KW - Islets of langerhans
KW - Probability density function
KW - Type 1 diabetes
KW - Weibull distribution
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UR - http://www.scopus.com/inward/citedby.url?scp=75149139995&partnerID=8YFLogxK
U2 - 10.3727/096368909X476968
DO - 10.3727/096368909X476968
M3 - Article
VL - 18
SP - 1223
EP - 1235
JO - Cell Transplantation
JF - Cell Transplantation
SN - 0963-6897
IS - 10-11
ER -