Enzyme immunoassay and characterization of pancreatic stone proteins in human urine.
An enzyme immunoassay of pancreatic stone protein (PSP) in human urine was developed. Mean analytical recovery of pure PSP-S2-5 added to urine was 102.3% (SD 5.9%), and the precision of the assay was 2.0-2.7% within an assay and 2.5-2.9% between assays. In healthy volunteers (age 20-55 years), the mean value of the PSP concentration, expressed as ratios to urine creatinine, was 129 +/- 88 (mean +/- SD) micrograms/g without any differences for sex. Urine PSP correlated with urine N-acetylglucosaminidase (NAG) (r = 0.354). The molecular forms of immunoreactive PSP in urine were characterized by using cation exchange chromatography (Mono S), SDS-PAGE, N-terminal sequence, and enzyme immunoassay analysis. The urine PSP, eluted at the position corresponding to PSP-S2-5 on cation exchange chromatography, was converted to PSP-S1 by trypsin digestion. The difference in mobility on SDS-PAGE between urine PSP and PSP-S2-5 seems to be due to a glycosylated undecapeptide (N-terminal 1-11). The proposed method offers a sensitive, specific, and reproducible tool for laboratory analysis of human urine PSP levels.
Tatemichi
N
N
Department of Clinical Chemistry, Maruko Pharmaceutical Co., Kasugai, Japan.
Takahashi
C
C
Hayakawa
S
S
Hayakawa
T
T
Shibata
T
T
Kitagawa
M
M
Sobajima
H
H
Nakae
Y
Y
D000118:Acetylglucosaminidase / Q000652:urine; D000328:Adult; D000595:Amino Acid Sequence; D002135:Calcium-Binding Proteins / Q000097:blood / Q000737:chemistry / Q000652:urine*; D002851:Chromatography, High Pressure Liquid; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques / Q000592:standards / Q000706:statistics & numerical data; D051847:Lithostathine; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D012015:Reference Standards; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D002135:Calcium-Binding Proteins; D051847:Lithostathine; D009419:Nerve Tissue Proteins; C497617:REG1A protein, human; D000118:Acetylglucosaminidase