Assessment of isolated islet equivalents • Cell Transplant Society 1996 • Michel van der Burg • Miracles.Media • 1MEMO_20251205_1 • Poster 3rd International Congress Cell Transplant Society, Miami (USA) Sep 29 – Oct 2, 1996 • TakeNode 1300e7cd-85a4-4cd0-9cbc-a88746e625ab • #IEQ #diabetes #islets #transplant #methods #CTRMS

IEQ – Islet Equivalent

IEQ islet stands for Islet Equivalent, a standard unit used to measure the total volume of islets (clusters of insulin cells and other hormone-producing cells in the pancreas). It is defined as a single spherical islet with a diameter of 150 µm. The IEQ is a crucial parameter for assessing the quantity of islets for procedures like clinical islet transplantation, which is a treatment for type 1 diabetes.

Modified international procedure

Following a consensus report in 1989 – 1990 by Ricordi et al (1a, 1b) on islet isolation assessment, the total volume of isolated islets is generally expressed in the number of islet equivalents (IEQs) — defined as islets of 150 µm diameter— and many centers use the advocated now classic international procedure (CIP) of sizing all islets in classes with 50-µm increments (i.e., 50–100, 100–150, etc.) for calculation of the number of IEQs. For each class the number of IEQs are calculated by multiplying the islet counts with a conversion factor — based on the mean volume of that class.

A modified international procedure — based on our conventional Leiden procedure (2,3) with islet sizing in classes with 25-µm increments — is suggested for accurate assessment of the IEQs especially when isolation yields mostly smaller islets, in our paper ‘Assessment of isolated islet equivalents’ presented at the 3rd International Congress Cell Transplant Society, Miami (USA) Sep 29 – Oct 2, 1996, in both a poster (4) , and proceedings paper (5). A photo of the original poster , (retrieved somewhat wrinkled 30 years later from my archive), is posted here, as well as a pdf from the (corrected proof) manuscript of the proceedings paper below (6).

The Cell Transplant Society was founded in 1991, and has been renamed the Cell Transplant and Regenerative Medicine Society (CTRMS).

Notes

1a. Ricordi C, Gray DW, Hering BJ, Kaufman DB, Warnock GL, Kneteman NM, Lake SP, London NJ, Socci C, Alejandro R, et al. Islet isolation assessment in man and large animals. Acta Diabetol Lat. 1990 Jul-Sep;27(3):185-95. doi: 10.1007/BF02581331. PMID: 2075782.

1b. Quantitative And Qualitative Standards For Islet Isolation Assessment In Man And Large Mammals. International Workshop during the 2nd Congress on Pancreas and Islet Transplantation (1989). Camillo Ricordi. Archive Michel van der Burg • Miracles•Media • 1MEMO_20251206_07 . Available from Dec 6, 2025 URL https://michelvanderburg.com/2025/12/06/

2. Van der Burg MPM, Guicherit OR, Frölich M, Scherft JP, Prins FA, Bruijn JA, Gooszen HG. Assessment of islet isolation efficacy in dogs. Cell Transplant. 1994 Jan-Feb;3(1):91-101. doi: 10.1177/096368979400300113. PMID: 8162296.

3. Paper (Notes 2) included as Chapter 3 in my doctoral thesis (Leiden University, November 1994) : Assessment of islet isolation efficacy in dogs. In : Van der Burg MPM. Pancreatic islet transplantation: studies on the technique and efficacy of islet isolation and transplantation ( Chapter 3). (Doctoral Thesis, Leiden University, 1994), Paperback (1994, Nov 9) Boskoop: Van der Burg (ISBN 9080216410); E-book (2022, Oct 25) Boskoop: Michel van der Burg | Miracles•Media ( ISBN 9789080216402). Retrieved (Nov 24th, 2025) from Leiden University Scholarly Publications, Persistent URL https://hdl.handle.net/1887/3486604 . Direct link to file Chapter 3 , URL https://scholarlypublications.universiteitleiden.nl/access/item%3A3486610/view

4. Van der Burg MPM, Scheringa M, Basir I, Bouwman E. Assessment of isolated islet equivalents. Poster presented at the Third Int. Congress Cell Transplant Soc., Miami (USA) Sept. 29 – Oct. 2, 1996.
In : Assessment of isolated islet equivalents • Cell Transplant Society 1996 • Michel van der Burg • Miracles.Media • @1MEMO 20251205 • URL https://michelvanderburg.com/2025/12/05 • File 1MEMO_20251205_1 • TakeNode 1300e7cd-85a4-4cd0-9cbc-a88746e625ab

5. Van der Burg MPM, Scheringa M, Basir I, Bouwman E. Assessment of isolated islet equivalents. Transplant Proc. 1997 Jun;29(4):1971-1973. doi: 10.1016/s0041-1345(97)00188-7. PMID: 9193483.

6. Manuscript (corrected proof for Transplant Proc paper PMID: 9193483). Van der Burg MPM, Scheringa M, Basir I, Bouwman E. Assessment of isolated islet equivalents • 1MEMO_20251205_2 • TakeNode 48380f3c-b3f7-416e-90bb-ad6c53129e46 • PDF available below , File 1MEMO_20251205_2

#IEQ #diabetes #islets #transplant #methods #CTRMS

Citation info : Assessment of isolated islet equivalents • Cell Transplant Society 1996 • Michel van der Burg • Miracles.Media • @1MEMO 20251205 • TakeNode 1300e7cd-85a4-4cd0-9cbc-a88746e625ab / 48380f3c-b3f7-416e-90bb-ad6c53129e46 • URL https://michelvanderburg.com/2025/12/05