A new radioimmunoassay for the detection of small amounts of white cells and platelets in red cell concentrates: implications for blood transfusion.
In the procedure for quality control of red cell concentrates, made white cell (WBC)-poor by filtration, the particle-counting technique was found to be insufficiently sensitive in detecting the remaining WBCs and platelets. Therefore, direct radioimmunoassays were developed using murine monoclonal antibodies specific for platelets, granulocytes, and T lymphocytes. The sensitivity for platelets was 40 x 10(3) per mL, that for granulocytes was 10 x 10(3) per mL (starting from 0.2 mL of red cell filtrate), and that for T lymphocytes was 0.006 x 10(6) per mL (starting from 5 mL) and 0.0015 x 10(6) per mL (starting from 50 mL). These direct assays were used in experiments on filtration with three types of filters: the Cellselect B-1005, B-1014 and the B-1013 (bedside filter). After filtration of 1 unit of blood cell suspension through the B-1005, the number of remaining platelets was found to vary between less than or equal to 0.04 x 10(6) and greater than 15 x 10(6) per mL (n = 16); after filtration through the B-1013 filter, the remaining platelets were greater than 0.04 x 10(6) per mL. Upon filtration of a second unit of blood cell suspension through the B-1013 filter, the number of remaining platelets varied between less than or equal to 0.04 x 10(6) and 5 x 10(6). In both filter types, the number of remaining granulocytes was always less than 0.01 x 10(6) per mL. A study of T-lymphocyte contamination revealed that, upon filtration of 1 unit of blood through the B-1005, T-lymphocyte numbers were less than or equal to 0.0015 x 10(6) to 0.15 x 10(6) per mL (starting from 5 and 50 mL); upon filtration through the B-1013 filter, the number of remaining T lymphocytes varied between less than or equal to 0.006 x 10(6) and 0.2 x 10(6) per mL (starting from 5 mL). After filtration of a second unit of blood cell suspension through the B-1013 filter, the number of remaining T lymphocytes ranged from less than or equal to 0.006 x 10(6) to 0.1 to 0.5 x 10(6) per mL (starting from 5 mL). The direct radioimmunoassay is an improvement over the present electronic particle-counting techniques with regard to both sensitivity and specificity and may therefore be useful in quality control procedures in blood transfusion as well as in the development of new filters.
Webster
M R
MR
Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, University of Amsterdam.
Prins
H K
HK
Huisman
J G
JG
D000911:Antibodies, Monoclonal; D001792:Blood Platelets / Q000166:cytology*; D001803:Blood Transfusion; D002469:Cell Separation; D017707:Erythrocyte Transfusion; D005374:Filtration; D006098:Granulocytes / Q000166:cytology; D007958:Leukocyte Count; D007962:Leukocytes / Q000166:cytology*; D010976:Platelet Count; D011786:Quality Control; D011863:Radioimmunoassay; D013601:T-Lymphocytes
D000911:Antibodies, Monoclonal