Nijsten M W, Olinga P, The T H, de Vries E G, Koops H S, Groothuis G M, Limburg P C, ten Duis H J, Moshage H, Hoekstra H J, Bijzet J, Zwaveling J H
Department of Surgery, University Hospital Groningen, and the Groningen Institute for Drug Studies, The Netherlands.
Crit Care Med. 2000 Feb;28(2):458-61. doi: 10.1097/00003246-200002000-00028.
Procalcitonin (PCT) is a 13 kD protein of which plasma concentrations are strongly increased in inflammatory states. PCT concentrations are claimed to have a more powerful discriminatory value for bacterial infection than the acute phase proteins serum amyloid A (SAA) or C-reactive protein (CRP). The source of production and its mechanism of induction are unknown. We investigated the inducibility of PCT both in vivo and in vitro and compared the behavior of PCT with those of SAA and CRP.
A prospective descriptive patient sample study and a controlled liver tissue culture study.
A university hospital.
Cancer patients who were treated with human tumor necrosis factor-alpha (rhTNF-alpha; 5 patients) or interleukin-6 (rhIL-6; 7 patients).
Serial serum samples were collected for analysis of concentrations of PCT, SAA, and CRP. In the TNF-alpha group, frequent sampling was performed on the first day to allow analysis of initial responses. In a human liver slice model, the release of PCT, SAA, and CRP was measured on induction with rhTNF-alpha and rhIL-6 for 24 hrs. We found that PCT displayed acute phase reactant behavior in vivo after administration of both rhTNF-alpha and rhIL-6. After rhTNF-alpha-administration, PCT reached half-maximal concentrations within 8 hrs, 12 hrs earlier than either SAA or CRP did. PCT, SAA, and CRP were produced in detectable quantities by liver tissue in vitro. PCT production by liver slices was enhanced after stimulation with rhTNF-alpha or rhIL-6; SAA and CRP concentrations were elevated after stimulation with rhTNF-alpha.
We found that PCT and acute phase proteins such as CRP are induced by similar pathways. The liver appears to be a major source of PCT production. Thus, PCT may be considered an acute phase protein. The different kinetics of PCT, rather than a fundamentally different afferent pathway, may explain its putative diagnostic potential to discriminate bacterial infection from other causes of inflammation.
降钙素原（PCT）是一种13 kD的蛋白质，其血浆浓度在炎症状态下会大幅升高。据称，PCT浓度对细菌感染的鉴别价值比急性期蛋白血清淀粉样蛋白A（SAA）或C反应蛋白（CRP）更强。其产生来源及其诱导机制尚不清楚。我们在体内和体外研究了PCT的诱导性，并将PCT的行为与SAA和CRP的行为进行了比较。
一项前瞻性描述性患者样本研究和一项对照肝组织培养研究。
一家大学医院。
接受重组人肿瘤坏死因子-α（rhTNF-α；5例）或白细胞介素-6（rhIL-6；7例）治疗的癌症患者。
采集系列血清样本以分析PCT、SAA和CRP的浓度。在TNF-α组，第一天进行频繁采样以分析初始反应。在人肝切片模型中，用rhTNF-α和rhIL-6诱导24小时后测量PCT、SAA和CRP的释放。我们发现，给予rhTNF-α和rhIL-6后，PCT在体内表现出急性期反应物的行为。给予rhTNF-α后，PCT在8小时内达到最大浓度的一半，比SAA或CRP早12小时。肝组织在体外可产生可检测量的PCT、SAA和CRP。用rhTNF-α或rhIL-6刺激后，肝切片产生的PCT增加；用rhTNF-α刺激后，SAA和CRP浓度升高。
我们发现PCT和CRP等急性期蛋白由相似途径诱导产生。肝脏似乎是PCT产生的主要来源。因此，PCT可被视为一种急性期蛋白。PCT不同的动力学特性，而非根本不同的传入途径，可能解释了其在鉴别细菌感染与其他炎症原因方面的假定诊断潜力。
