Oregon State University, Eastern Oregon Agricultural Research Center, Burns, OR 97720, USA.
J Anim Physiol Anim Nutr (Berl). 2013 Jun;97(3):531-6. doi: 10.1111/j.1439-0396.2012.01298.x. Epub 2012 Apr 5.
The objective was to compare different procedures for determination of haptoglobin in bovine plasma. Nine Angus steers were vaccinated against Mannheimia haemolytica to stimulate an acute-phase response. Blood samples were collected immediately prior to vaccination (day 0), and on days 1, 3, 5, 7 and 10. Plasma samples were frozen in duplicates at -80 °C. One set of the duplicates was analysed for haptoglobin concentrations using a commercial ELISA kit. A day effect was detected (p < 0.01) because haptoglobin peaked on day 3 and returned to baseline on day 7 relative to vaccination. The second duplicate was analysed using a procedure that measures haptoglobin-haemoglobin complexing by estimating differences in peroxidase activity (CPPA) with results expressed as optical density. Further, based on the ELISA results, the plasma sample with the greatest haptoglobin concentration was also serially diluted into a plasma sample with negligible haptoglobin concentration from the same steer (1:1 through 1:1024 dilution). These dilutions were used within the CPPA method to generate a standard curve and estimate plasma haptoglobin concentrations (CPPA + STD). A linear standard curve was generated (r(2) = 0.99). A day effect similar to the ELISA method was detected for the CPPA and CPPA + STD methods (p < 0.01). Results obtained from CPPA and ELISA methods were positively correlated (r = 0.97; p < 0.01). The values generated by the CPPA + STD procedure were similar (p = 0.38) compared to the values generated by the ELISA method. In conclusion, assessing concentrations of haptoglobin in bovine plasma using the CPPA and CPPA + STD methods generate highly correlated or similar results, respectively, compared to ELISA. Therefore, the CPPA + STD and CPPA methods can be used as a less expensive alternative to ELISA to determine concentrations or monitor changes in plasma haptoglobin in bovine samples.
本研究旨在比较不同方法在测定牛血浆中触珠蛋白（haptoglobin）的效果。9 头安格斯阉牛接种曼海姆氏菌（Mannheimia haemolytica）疫苗以刺激急性期反应。在接种前（第 0 天）及接种后第 1、3、5、7 和 10 天采集血样。采集的血浆样本以 2 份为一组，立即置于-80°C 下冷冻。一组样本使用商业 ELISA 试剂盒分析触珠蛋白浓度。研究发现存在日效应（p<0.01），因为与接种相比，触珠蛋白在第 3 天达到峰值，并在第 7 天恢复到基线。第二组样本使用通过估计过氧化物酶活性（CPPA）差异来测量触珠蛋白-血红蛋白复合物形成的方法进行分析，结果以光密度表示。此外，根据 ELISA 结果，从同一只牛的血浆样本中选择具有最大触珠蛋白浓度的样本，依次稀释至具有可忽略触珠蛋白浓度的样本（1:1 到 1:1024 稀释）。这些稀释液用于 CPPA 方法中生成标准曲线并估计血浆触珠蛋白浓度（CPPA+STD）。生成了线性标准曲线（r2=0.99）。CPPA 和 CPPA+STD 方法均检测到与 ELISA 方法类似的日效应（p<0.01）。CPPA 和 ELISA 方法获得的结果呈正相关（r=0.97；p<0.01）。CPPA+STD 程序生成的值与 ELISA 方法生成的值相似（p=0.38）。结论：与 ELISA 方法相比，CPPA 和 CPPA+STD 方法分别用于评估牛血浆中触珠蛋白浓度时，生成的结果高度相关或相似。因此，CPPA+STD 和 CPPA 方法可作为 ELISA 的廉价替代方法，用于确定牛样本中触珠蛋白的浓度或监测其变化。
