Stinghen Sérvio T, Moura Juliana F, Zancanella Patrícia, Rodrigues Giovanna A, Pianovski Mara A, Lalli Enzo, Arnold Dodie L, Minozzo João C, Callefe Luis G, Ribeiro Raul C, Figueiredo Bonald C
Centro de Genética Molecular e Pesquisa do Câncer em Crianças (CEGEMPAC), Curitiba, PR, CEP 80030-110, Brazil.
J Biomed Biotechnol. 2006;2006(5):56087. doi: 10.1155/JBB/2006/56087.
Human placental (hPLAP) and germ cell (PLAP-like) alkaline phosphatases are polymorphic and heat-stable enzymes. This study was designed to develop specific immunoassays for quantifying hPLAP and PLAP-like enzyme activity (EA) in sera of cancer patients, pregnant women, or smokers. Polyclonal sheep anti-hPLAP antibodies were purified by affinity chromatography with whole hPLAP protein (ICA-PLAP assay) or a synthetic peptide (aa 57-71) of hPLAP (ICA-PEP assay); the working range was 0.1-11 U/L and cutoff value was 0.2 U/L EA for nonsmokers. The intra- and interassay coefficients of variation were 3.7%-6.5% (ICA-PLAP assay) and 9.0%-9.9% (ICA-PEP assay). An insignificant cross-reactivity was noted for high levels of unheated intestinal alkaline phosphatase in ICA-PEP assay. A positive correlation between the regression of tumor size and EA was noted in a child with embryonal carcinoma. It can be concluded that ICA-PEP assay is more specific than ICA-PLAP, which is still useful to detect other PLAP/PLAP-like phenotypes.
人胎盘碱性磷酸酶（hPLAP）和生殖细胞碱性磷酸酶（类PLAP）是具有多态性且热稳定的酶。本研究旨在开发特异性免疫测定法，用于定量癌症患者、孕妇或吸烟者血清中的hPLAP和类PLAP酶活性（EA）。用完整的hPLAP蛋白通过亲和层析纯化多克隆羊抗hPLAP抗体（ICA-PLAP测定法）或hPLAP的合成肽（氨基酸57-71）（ICA-PEP测定法）；非吸烟者的工作范围为0.1-11 U/L，临界值为0.2 U/L EA。ICA-PLAP测定法的批内和批间变异系数分别为3.7%-6.5%，ICA-PEP测定法为9.0%-9.9%。在ICA-PEP测定法中，未加热的肠碱性磷酸酶水平较高时，交叉反应不明显。在一名胚胎癌患儿中，观察到肿瘤大小回归与EA之间呈正相关。可以得出结论，ICA-PEP测定法比ICA-PLAP更具特异性，ICA-PLAP在检测其他PLAP/类PLAP表型方面仍然有用。
