MULTIENZYME CONTROL SERUM (SERACLEAR-HE) CONTAINING HUMAN ENZYMES FROM ESTABLISHED CELL-LINES AND OTHER SOURCES .3. EVALUATION AS CANDIDATEWORKING ENZYME REFERENCE MATERIAL FOR GAMMA-GLUTAMYL-TRANSFERASE
A. Eto et al., MULTIENZYME CONTROL SERUM (SERACLEAR-HE) CONTAINING HUMAN ENZYMES FROM ESTABLISHED CELL-LINES AND OTHER SOURCES .3. EVALUATION AS CANDIDATEWORKING ENZYME REFERENCE MATERIAL FOR GAMMA-GLUTAMYL-TRANSFERASE, Clinical chemistry, 42(12), 1996, pp. 2008-2014
Seraclear-HE, containing gamma-glutamyltransferase (GGT, EC 2.3.2.2) d
erived from the cell culture of a human macrophage cell line, was eval
uated as a candidate enzyme reference material (ERM) to calibrate rout
ine methods in terms of a Reference Method for GGT, We have compared t
his preparation with commercially available materials, including Certi
fied Reference Material 319, at 30 degrees C and 37 degrees C with res
pect to kinetic properties and with respect to commutability between t
he Reference Method and each of 15 analytical procedures involving fir
e structurally different donor substrates, GGTs of human origin are fa
r more commutable with reagents of varied types than are GGTs derived
from animals, Calibration of 44 patients' sera with Seraclear-HE decre
ased average intermethod variation from 20% to similar to 4%, whereas
GGTs of animal origin showed intermethod variations of similar to 30%
with no benefit from calibration, Seraclear-HE is promising as a secon
dary or working ERM to be used as an intermethod calibrator.