PB0318 - Evaluation of a novel ADAMTS13 activity reagent using fully automated analyzer

Sunday, June 25, 2023

18:30 – 19:30 ET

Room: Exhibition

Presenting Author(s)

MK

Masayuki Kubo, MD

Medical staff
Department of Blood Transfusion Medicine, Nara Medical University
Kashihara, Nara, Japan

Co-Author(s)

KK

Kazuyasu Konko

Senior Engineer
Protein Technology Group, Reagent Engineering, Sysmex Corporation
Kobe, Hyogo, Japan
EK

Emi Kinoshita

Staff
Protein Technology Group, Reagent Engineering, Sysmex Corporation
Kobe, Hyogo, Japan
SU

Satoshi Uemae

Director
Hemostasis Business Development, ICH Business, Sysmex Corporation
Kobe, Hyogo, Japan
KK

Katsushi Kobayashi

Vice President
Protein Technology Group, Reagent Engineering, Sysmex Corporation
Kobe, Hyogo, Japan
YF

Yoshihiro Fujimura

Professor emeritus
Department of Blood Transfusion Medicine, Nara Medical University
Kashihara, Nara, Japan
MM

Masanori Matsumoto

Professor
Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Nara, Japan
Kashihara, Nara, Japan

Background: ADAMTS13 activity is essential for diagnosing thrombotic thrombocytopenic purpura (TTP). TTP is a life-threatening disease that requires accurate and rapid measurement of ADAMTS13 levels. A novel ADAMTS13 activity reagent for a fully automated quantitative chemiluminescent enzyme immunoassay (CLEIA) was developed for rapid testing, with a reaction time of 17 min.

Aims: To evaluate the basic performance of a novel ADAMTS13 activity reagent and to compare assays using samples from patients with TTP.

Methods: We compared CLEIA using the prototype reagent on a fully automated analyzer with in-house FRETS-VWF73 assay and ADAMTS13-act ELISA “KAINOS” for 27 samples from patients with TTP during the acute phase or clinical remission and 24 samples from healthy donors. The evaluation of between-day precision and on-board stability was performed using three control specimens (low, 20.13 IU/dL; middle, 67.95 IU/dL; high, 99.93 IU/dL).

Results: ADAMTS13 activities measured by CLEIA with the novel reagent showed a good correlation with those measured by the in-house FRETS-VWF73 assay (r=0.98) and ELISA (r=0.89), as shown in Figure 1. However, in the high activity range, the levels of ADAMTS13 activity by CLEIA tended to be higher than those by ELISA. The three samples identified with < 10 IU/dl ADAMTS13 activity by the FRETS-VWF73 assay and ELISA were also consistent with < 10 IU/dl ADAMTS13 activity by CLEIA with the prototype reagent. The coefficients of variations of the three control specimens (low, middle, and high controls) were 3.8%, 3.4%, and 4.7%, respectively, for the between-day precision. In addition, the novel ADAMTS13 activity reagent was stable for 60 days.

Conclusion(s): The ADAMTS13 activity evaluated by CLEIA using our novel reagent was highly correlated with the current standard assay. It is a useful technique in the diagnosis and follow-up of TTP, as it can be performed rapidly using the fully automated analyzer.