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Cytological and Biomolecular Measuring Procedures

Working Group 8.32

Reference procedures for cell counting


EMRP (European Metrology Research Programme)
FKZ SIB54 Bio-SITrace

  07/2013 – 06/2016

  The EMRP is jointly funded by the EMRP participating countries within
  EURAMET and the European Union.



EMPIR (European Metrology Programme for Innovation and Research)
FKZ Opens external link in new window16SIP01 Bio-Stand

  04/2017 – 03/2020

  The project receives funding from the EMPIR programme co-financed 
  by the Participating States and from the European Union’s Horizon
  2020 research and innovation programme.


Gas buffered sample injection unit of a PTB reference flow cytometer

EMRP project BioSITrace

Determination of cell concentration is one of the most frequently requested quantities to support medical diagnostics and therapy. Lack of higher order reference methods and materials is a major hindrance for deriving traceability and measurement comparability. The EMRP-Project Opens external link in new windowBioSITrace 'Traceability for biologically relevant molecules and entities' develops such procedures and materials for the enumeration of nucleic acids, lipoproteins and cells. The work package lead by PTB develops and evaluates primary procedures based on flow cytometry and microscopy. A secondary reference procedure along the traceability chain can be based on relative enumerations of the target cell concentration to a calibrator concentration. The application of such procedures will allow manufacturers and end users on-site assessment of the performance of their instruments and protocols.

The research activities will also feed in national and international standardisation at DIN and ISO.
Opens external link in new windowISO 20391-1:2018(en)
Biotechnology — Cell counting — Part 1: General guidance on cell counting methods

Opens external link in new windowISO 20391-2:2019(en)
Biotechnology — Cell Counting — Part 2: Experimental design and statistical analysis to quantify counting method performance

Opens external link in new windowISO 20395:2019(en)
Biotechnology — Requirements for evaluating the performance of quantification methods for nucleic acid target sequences — qPCR and dPCR


1. Neukammer J, Kammel M, Höckner, J, Kummrow A, Ruf A.
Reference Procedure for the Measurement of Stem Cell Concentrations in Apheresis Products
Opens external link in new windowPTB-Mitteilungen 125 No2  (2015) 70-73,  English translation of the original version:
Neukammer J, Kammel M, Höckner J, Kummrow A, Ruf A.
Referenzverfahren zur Messung von Stammzellkonzentrationen
Opens external link in new windowBIOspektrum 03.15, (2015) 294-297, ISSN 0947-0867

2. Kammel M, Kummrow A, John M, Reitz S, Witt K., Neukammer J.
Flow cytometer for reference measurements of blood cell concentrations with low uncertainties
IEEE Transactions on Instrumentation and Measurement (TIM) : Opens external link in new windowSpecial Issue of IEEE International Symposium on Medical Measurements and Applications (2015), Turin, 09, April, 2015

3. Kammel, M.; Kummrow, A.; Neukammer, J.
Reference measurement procedures for the accurate determination of cell concentrations: present status and future developments
Opens external link in new windowJ. Lab. Med. 36 (2012) 25-34.

4. Stebbings R, Wang L, Sutherland J, Kammel M, Gaigalas AK, John M, Roemer B, Kuhne M, Schneider RJ, Braun M, Engel A, Dikshit D, Abbasi F, Marti GE, Sassi M, Revel L, Kim SK, Baradez M, Lekishvili T, Marshall D, Whitby L, Jing W, Ost V, Vonsky M, Neukammer J.
Quantification of Cells with Specific Phenotypes I: Determination of CD4+ Cell Count Per Microliter in Reconstituted Lyophilized Human PBMC Prelabeled with Anti-CD4 FITC Antibody
Opens external link in new windowCytometry A 87A (2015) 244-253