Sorensen N S, Tegtmeier C, Andresen L O, Piñeiro M, Toussaint M J M, Campbell F M, Lampreave F, Heegaard P M H
Department of Veterinary Diagnostics and Research, Danish Institute for Food and Veterinary Research, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
Vet Immunol Immunopathol. 2006 Sep 15;113(1-2):157-68. doi: 10.1016/j.vetimm.2006.04.008. Epub 2006 Jun 13.
The pig acute phase protein (APP) response to experimental Streptococcus suis (S. suis) infection was mapped by the measurement of the positive APPs C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin (Hp) and major acute phase protein (pig-MAP) and the negative APPs albumin and apolipoprotein (Apo) A-I. The aim was to elucidate the differences in the acute phase behaviour of the individual APPs during a typical bacterial septicaemic infection. Pigs were inoculated subcutaneously with live S. suis serotype 2 and blood was sampled before and on various days post inoculation (p.i.), until the pigs were killed and autopsied on day 14 p.i. Clinical signs (fever and lameness) were observed in four of the five inoculated pigs from day 2 p.i., and these pigs also had arthritic lesions at autopsy. CRP and SAA showed fast increases in serum concentrations, CRP being elevated from days 1 to 12 p.i. and peaking at 10 times the day 0-levels on day 1 p.i. SAA rose quickly to peak levels of 30-40 times the day 0-level on days 1-2 and returned to pre-inoculation level on day 5 p.i. Hp and pig-MAP showed slightly slower responses, both peaking around 5 days p.i. Hp was increased throughout the experiment with maximum levels around 10 times the day 0-levels, and pig-MAP was elevated on days 1-12 p.i. with peak levels of around seven times the day 0-levels. Apo A-I was decreased from days 1 to 8 and showed minimum levels of about 40% of day 0-levels around 1-2 days p.i. No clear pattern of changes in albumin levels could be identified. One pig, showing clinical signs on day 2 only, also showed an APP response, although of a relatively short duration, whereas three pigs presenting clinical signs for several days had a more protracted acute phase response. Remarkably, the one pig showing no clinical signs and no arthritic lesions showed an APP response comparable to that of the other, clinically affected pigs. Thus, both acute clinical and subclinical S. suis infection could be revealed by the measurement of one or more of the APPs CRP, SAA, Hp, pig-MAP and Apo A-I. The combined measurement of two or three APPs, including proteins with slow and fast kinetics, should be used to achieve the highest sensitivity for the detection of ongoing S. suis infection during a prolonged time period. A diagnostic tool based on such APP-measurements could considerably improve strategic control procedures for this important infection.
通过检测阳性急性期蛋白C反应蛋白（CRP）、血清淀粉样蛋白A（SAA）、触珠蛋白（Hp）和主要急性期蛋白（猪-MAP）以及阴性急性期蛋白白蛋白和载脂蛋白A-I，对猪对实验性猪链球菌（S. suis）感染的急性期蛋白（APP）反应进行了研究。目的是阐明在典型的细菌性败血症感染期间，各个APP急性期行为的差异。给猪皮下接种2型活猪链球菌，在接种前及接种后（p.i.）不同天数采集血液，直至在接种后第14天处死猪并进行尸检。从接种后第2天起，在5头接种猪中有4头观察到临床症状（发热和跛行），这些猪在尸检时也有关节炎病变。CRP和SAA的血清浓度迅速升高，CRP在接种后第1天至第12天升高，在接种后第1天达到0天水平的10倍峰值。SAA在第1 - 2天迅速上升至0天水平的30 - 40倍峰值，并在接种后第5天恢复到接种前水平。Hp和猪-MAP的反应稍慢，均在接种后约5天达到峰值。在整个实验过程中，Hp均升高，最高水平约为0天水平的10倍，猪-MAP在接种后第1天至第12天升高，峰值水平约为0天水平的7倍。载脂蛋白A-I在第1天至第8天下降，在接种后第1 - 2天左右达到最低水平，约为0天水平的40%。白蛋白水平未发现明显的变化模式。一头仅在第2天出现临床症状的猪也表现出APP反应，尽管持续时间相对较短，而三头出现临床症状数天较长的猪急性期反应更为持久。值得注意的是，一头未出现临床症状且无关节炎病变的猪表现出与其他临床受影响猪相当的APP反应。因此，通过检测一种或多种APP，即CRP、SAA、Hp、猪-MAP和载脂蛋白A-I，可揭示急性临床和亚临床猪链球菌感染。应联合检测两种或三种APP，包括具有慢动力学和快动力学的蛋白质，以在较长时间段内实现检测正在进行的猪链球菌感染的最高灵敏度。基于此类APP检测的诊断工具可显著改善对这种重要感染的战略控制程序。
