RT Journal Article
SR Electronic
T1 A critical evaluation of enzyme immunoassay kits for detection of antinuclear autoantibodies of defined specificities. II. Potential for quantitation of antibody content.
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP 68
OP 74
VO 29
IS 1
A1 Eng M Tan
A1 Josef S Smolen
A1 J Steven McDougal
A1 Marvin J Fritzler
A1 Thomas Gordon
A1 John A Hardin
A1 Joachim R Kalden
A1 Robert G Lahita
A1 Ravinder N Maini
A1 Westley H Reeves
A1 Naomi F Rothfield
A1 Yoshinari Takasaki
A1 Allan Wiik
A1 Merlin Wilson
A1 James A Koziol
YR 2002
UL http://www.jrheum.org/content/29/1/68.abstract
AB OBJECTIVE: To analyze the performance of different commercial enzyme immunoassay (EIA) kits for measuring antibody levels of antinuclear antibodies (ANA) specific for double stranded (ds) DNA, SSB/La, Sm, and Scl-70. METHODS: Twenty companies that were known major purveyors of EIA kits for detection of ANA were approached to determine their interest and willingness to participate in this study. The manufacturers were advised that they would be sent coded sera containing mixtures of the Arthritis Foundation/Centers for Disease Control reference reagents, and that they were to use their own test kits to analyze the antibody specificities of these sera and to report the data, in optical density (OD) units, or their equivalent. The analysts were blinded to the concentration of the antibodies and the specificities. RESULTS: Initially, 11 manufacturers out of 20 agreed to participate, but 2 subsequently withdrew. The commercial EIA kits have the potential of being able to quantitate specific autoantibody content to ds-DNA, SSB/La, Sm, and Scl-70. However, certain deficiencies in these kits were also detected, the most obvious being lack of uniformly good performance, with kits of certain manufacturers showing exceptional accuracy in 3 out of 4 of their antibody-specific kits and poor accuracy for a 4th kit. CONCLUSION: It is important for clinicians to appreciate that there is marked inter-manufacturer variation in the performance of EIA kits used as an aid in the diagnosis of systemic rheumatic diseases. Manufacturers need to exercise constant surveillance of kit performance and to provide assurance that such is being done. Improved EIA kits would lend themselves to reliable quantitation of antibody levels in human sera and help to determine whether serial measurement of antibody levels might be useful in monitoring disease activity.