OBJECTIVES: Haptoglobin (Hp) phenotypes 1-1, 2-1, and 2-2 are associated with inflammatory diseases. Since their biochemical structures are rather heterogeneous, it is necessary to accurately determine the plasma Hp levels. DESIGN AND METHODS: Immunodiffusion, immunoturbidimetric, and noncompetitive ELISA were conducted to determine the differences in immunoreactivity among Hp phenotypes and to verify that such difference may significantly affect the outcome of Hp determinations. A novel ELISA using phenotype-matched calibrators was performed to compared with a commercial GenWay ELISA kit using a single calibrator in normal healthy males. RESULTS: In immunodiffusion and immunoturbidimetric assays, the immunoreactivity of Hp 1-1 was markedly higher than 2-1 and 2-2, while an opposite result was observed using an ELISA. The latter was primarily due to the repeated antigenic epitopes in polymeric 2-1 and 2-2. Thus, Hp levels could be significantly over- or underestimated depending on the method. An accurate ELISA could be achieved when using each type-specific Hp calibrator matched to each type subject. We show the mean levels of Hp 1-1 subjects (n=16; 184+/-42 mg/dL) to be significantly and differentially greater than 2-1 (n=28; 153+/-55 mg/dL) (p<0.05) and 2-2 (n=24; 93+/-54 mg/dL) (p<0.01) subjects. CONCLUSIONS: Due to the diverse immunochemical structure among the Hp types, phenotyping should be performed in all the patients and a type-matched Hp calibrator should be used in clinical Hp determination.
OBJECTIVES:Haptoglobin (Hp) phenotypes 1-1, 2-1, and 2-2 are associated with inflammatory diseases. Since their biochemical structures are rather heterogeneous, it is necessary to accurately determine the plasma Hp levels. DESIGN AND METHODS: Immunodiffusion, immunoturbidimetric, and noncompetitive ELISA were conducted to determine the differences in immunoreactivity among Hp phenotypes and to verify that such difference may significantly affect the outcome of Hp determinations. A novel ELISA using phenotype-matched calibrators was performed to compared with a commercial GenWay ELISA kit using a single calibrator in normal healthy males. RESULTS: In immunodiffusion and immunoturbidimetric assays, the immunoreactivity of Hp 1-1 was markedly higher than 2-1 and 2-2, while an opposite result was observed using an ELISA. The latter was primarily due to the repeated antigenic epitopes in polymeric 2-1 and 2-2. Thus, Hp levels could be significantly over- or underestimated depending on the method. An accurate ELISA could be achieved when using each type-specific Hp calibrator matched to each type subject. We show the mean levels of Hp 1-1 subjects (n=16; 184+/-42 mg/dL) to be significantly and differentially greater than 2-1 (n=28; 153+/-55 mg/dL) (p<0.05) and 2-2 (n=24; 93+/-54 mg/dL) (p<0.01) subjects. CONCLUSIONS: Due to the diverse immunochemical structure among the Hp types, phenotyping should be performed in all the patients and a type-matched Hp calibrator should be used in clinical Hp determination.
Authors: Tracey L Weissgerber; Paula L McGee; Leslie Myatt; John C Hauth; Michael W Varner; Ronald J Wapner; John M Thorp; Brian M Mercer; Alan M Peaceman; Susan M Ramin; Philip Samuels; Anthony C Sciscione; Margaret Harper; George Saade; Yoram Sorokin Journal: J Matern Fetal Neonatal Med Date: 2014-01-13
Authors: Catherine F M Bowden; Anson C K Chan; Emily J W Li; Angelé L Arrieta; Lindsay D Eltis; Michael E P Murphy Journal: J Biol Chem Date: 2017-11-06 Impact factor: 5.157