Immunofluorometric assay of pepsinogen C and preliminary clinical applications.
We developed mouse monoclonal antibodies (Abs) against pepsinogen C with highly purified antigen isolated from gastric mucosa. The Abs were used to construct a two-site sandwich-type assay for pepsinogen C with time-resolved fluorometry as a detection technique. The assay has a detection limit of 0.1 microgram/L and is precise (within-run and day-to-day CVs < 11%). We used this assay to measure pepsinogen C in seminal plasma, breast cyst fluid, amniotic fluid, male and female serum, serum from patients with prostate cancer, urine, breast tumor cytosolic extracts, breast milk, and cerebrospinal fluid. Highest pepsinogen C concentrations were in seminal plasma, followed by breast cyst fluid and amniotic fluid. We found no correlation between prostate-specific antigen concentrations and concentrations of pepsinogen C in serum of prostate cancer patients, and concluded that this marker is not useful for either diagnosing or monitoring prostatic carcinoma. The availability of a highly sensitive, reliable, and convenient method for quantifying pepsinogen C will allow investigations into the possible diagnostic value of this analyte in various clinical conditions, including benign breast diseases, breast cancer, fertility, and pregnancy.
Diamandis
E P
EP
Department of Pathology, Mount Sinai Hospital, Canada. epd@eric.on.ca
Nadkarni
S
S
Bhaumik
B
B
Abdelrahman
A
A
Melegos
D N
DN
Borchert
G
G
Black
M H
MH
Alonso
M
M
Salas
A
A
de los Toyos
J R
JR
Sampedro
A
A
López-Otín
C
C
D000653:Amniotic Fluid / Q000201:enzymology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D001826:Body Fluids / Q000201:enzymology*; D001943:Breast Neoplasms / Q000201:enzymology; D002138:Calibration; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D005260:Female; D015200:Fluoroimmunoassay / Q000379:methods*; D006801:Humans; D008297:Male; D008895:Milk, Human / Q000201:enzymology; D010435:Pepsinogens / Q000032:analysis* / Q000276:immunology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000201:enzymology; D015203:Reproducibility of Results; D012661:Semen / Q000201:enzymology; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; D015415:Biomarkers; D010435:Pepsinogens; D017430:Prostate-Specific Antigen