A new immunoassay for TPA determination has been developed in which anti-cytokeratin monoclonal antibodies are used. A three-MAb combination with different anti-cytokeratin antibody specificities has been selected to mimic the complex pattern found for the polyclonal anti-TPA antibody. The accuracy of the assay is good, as judged from analytical recovery experiments, analysis of quality-assessment samples and comparison with the polyclonal Prolifigen TPA IRMA. No significant interferences or cross-reactivities have been identified. The lower limit of detection of the assay (mean + 3 SD of the zero standard) is below 15 U/L and the imprecision in low, giving a working range of 15-4000 UIL.
The improved handling of the assay, including a single incubation step of 2 hours with shaking at room temperature, results in a narrower normal distribution, thereby giving a better separation of normal and pathological samples.
BjörklundB., BjörklundV.Antigenicity of pooled human malignant and normal tissues by cyto-immunological technique: presence of an insoluble heat-labile tumor antigen.Int Arch Allergy1957; 10: 153–84.
2.
BjörklundB., LundbladG., BjörklundV.Antigenicity of pooled human malignant and normal tissues by cyto-immunological technique: II.Nature of tumor antigen. Int Arch Allergy1958; 12: 241–61.
3.
BjörklundB.On the nature and clinical use of tissue polypeptide antgen (TPA).Tumor Diagnostik1980; 1: 9–20.
4.
NathrathW.B.J., HeidenkummerP., BjörklundV., BjörklundB.Distribution of tissue polypeptide antigen (TPA) in normal human tissues: immunohistochemical study on unfixed, methanol-, ethanol-, and formalin-fixed tissues.J Histochem Cytochem1985; 33: 99–109.
LüningB., NilssonU.Sequence homology between tissue polypeptide antigen (TPA) and intermediate filament (IF) proteins.Acta Chem Scand B1983; 37: 731–3.
10.
KirschJ., OehrP., WinklerC.Localization of tissue polypeptide antigen in interphase HeLa cells by immunofluorescence microscopy.Tumordiagn Ther1983; 4: 189–228.
11.
KirschJ., OehrP., WinklerC.Display of TPA in interphase and mitosis (meeting abstract). In: PeetersH. ed. Protides Biol Fluids Proc Colloq 32.Oxford: Pergamon Press, 1985; 723–6.
12.
KirschJ., OehrP., WinklerC.Localization of tissue polypeptide antigen in HeLa cells during mitosis as revealed by immunofluorescence microscopy.Tumordiagn Ther1984; 5: 122–6.
13.
WeberK., OsbornM., MollR., WiklundB., LüningB.Tissue polypeptide antigen (TPA) is related to the non-epidermal keratins 8, 18 and 19 typical of simple and non-squamous epithelia: re-evaluation of a human tumor marker.EMBO J1984; 3: 2707–14.
14.
MollR.Epithelial tumor markers: cytokeratins and tissue polypeptide antigen (TPA).Curr Top Pathol1987; 77: 71–101.
15.
MellerickD.M., OsbornM., WeberK.On the nature of serological tissue polypeptide antigen (TPA); monoclonal keratin 8, 18 and 19 antibodies react differently with TPA prepared from human cultured carcinoma cells and TPA in human serum.Oncogene1990; 5: 1007–17.
16.
LüthgensM., SchlegelG.The clinical value of tissue polypeptide antigen (TPA): A review.J Tumor Marker Oncol1987; 2: 261–71.
17.
PfaffM.O'Conner R, Vollmers HP, Müller-Hermelink HK.Human monoclonal antibody against a tissue polypeptide antigen-related protein from a patient with a signet-ring cell carcinoma of the stomach. Cancer Res1990; 50: 5192–8.
18.
MollR., FrankeW.W., SchillerD., GeigerB., KreplerR.The catalog of human cytokeratins: Patterns of expression in normal epithelia, tumors and cultured cells - review.Cell1982; 31: 11–24.
19.
SundströmB.E., NathrathW.B.J., StigbrandT.I.Diversity in immunoreactivity of tumor-derived cytokeratin monoclonal antibodies.J Histochem Cytochem1989; 37: 1845–54.
LaemmliU.K.Cleavage of structural proteins during the assembly of the head of bacteriophage T4.Nature1970; 227: 680–5.
22.
TowbinH., StaehelinT., GordonJ.Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets.Procedure and some applications. Proc Natl Acad Sci USA1979; 76: 4350–4.
23.
HarlowE., LaneD.In: Antibodies, a laboratory manual.Cold Spring Harbor Laboratory, 1988; 608.
24.
HunterW.H., GreenwoodF.C.Preparation of iodine-131 labeled human growth hormone of high specific activity.Nature1962; 194: 495–6.
SundströmB.E., BrundellJ., StigbrandT.I., HanssonL-O, BombardieriE.Cytokeratins and cancer. 10th International Conference of Human Tumor Markers, Bonn, Germany 1993.
27.
LüningB.On the historical clinical data for tissue polypeptide antigen.Clin Chem1994; 40: 1607–8.
