不同液体如血清中急性期蛋白(APPs)的测定,用超灵敏测定法测量的唾液和肉汁可用于评估田间条件下猪种群的疾病状况。肝脏是血清APP的主要生产场所,但是可以在不同于血液的体液中确定的APP的来源仍然未知。这项研究的目的是阐明三种APP的起源:C反应蛋白(CRP),唾液和肉汁中的血清淀粉样蛋白A(SAA)和结合珠蛋白(Hp)。在肝脏中测量这些蛋白质的mRNA表达,通过定量PCR将唾液腺和膈肌与血清中的蛋白质水平进行比较,唾液和肉汁,分别在健康和自然患病的动物中。不出所料,在患病动物的所有体液中,所有APP的浓度均显着较高。所有APPsmRNA水平在膈肌组织中都很低,表达与疾病状态无关。相比之下,我们发现SAA和HpmRNA在患病动物的唾液腺中表达水平较高,而CRPmRNA未检测到。我们的数据表明,肉汁中存在的APP主要来自血清。肉汁中两种蛋白质水平与血清中两种蛋白质水平的良好相关性也支持了这一假设。Further,两组动物内APP水平的变异性较低,建议将肉汁作为替代取样材料。唾液中确定的APP水平,然而,似乎是由于当地产量增加,除了CRP,这表明唾液腺对疾病有反应。这些发现与确定唾液作为健康监测计划的首选诊断样本有关,由于收集的技术和道德优势。
Acute phase proteins (APPs) determination in different fluids like serum, saliva and meat juice measured with ultrasensitive assays can be used to evaluate the disease status of porcine populations under field conditions. Liver is the main production site of serum APPs, but the origin of APPs that can be determined in body fluids different from blood remains unknown. The objective of this
study was to clarify the origin of three APPs: C-reactive protein (CRP), serum amyloid A (SAA) and haptoglobin (Hp) in saliva and meat juice. The mRNA expression of these proteins was measured in liver, salivary gland and diaphragmatic muscle by quantitative PCR and compared with the protein levels in serum, saliva and meat juice, respectively in healthy and naturally diseased animals. As expected, concentrations of all APP were significantly higher in all body fluids from diseased animals. Levels of all APPs mRNA were very low in diaphragmatic muscle tissue, and the expression was independent of the disease status. In contrast, we found higher expression levels of SAA and Hp mRNA in the salivary gland of diseased animals, while CRP mRNA was not detected. Our data indicate that the APP present in meat juice derived predominantly from serum. This assumption is also supported by the good correlation of the levels of both proteins in meat juice with those in serum. Further, the lower variability of the APP levels within the two groups of animals, suggests meat juice as an alternate sampling material. The APP levels that are determined in saliva, however, appear to result from an increased local production except for CRP, indicating that the salivary gland responds to disease. These findings are relevant for the establishment of saliva as the preferred diagnostic sample for health monitoring programmes, due to the technical and ethical advantages of the collection.