Mazza Maria, Guglielmetti Chiara, Pagano Marianna, Sciuto Simona, Ingravalle Francesco, Martucci Francesca, Caramelli Maria, Acutis Pier Luigi
Italian Reference Centre for TSEs, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Via Bologna 148-10154, Turin, Italy.
J Vet Diagn Invest. 2012 Sep;24(5):971-5. doi: 10.1177/1040638712457352.
Prion protein (PrP) is encoded by the PRNP gene, which is highly polymorphic in goats, with polymorphisms encoding amino acid substitutions at the protein level. In the current study, the reactivity of monoclonal antibody (mAb) F99/97.6.1 in binding PrP from goats polymorphic at PRNP codon 222 was investigated. Nervous tissue from 30 scrapie-negative goats with 3 different genotypes (222Q/Q, 222Q/K, and 222K/K) was analyzed by Western blot using mAbs P4 and F99/97.6.1. Although PrP was detected in all 30 samples by mAb P4, detection of PrP by mAb F99/97.6.1 was limited to 222Q/Q (12/12). No PrP was detected by mAb F99/97.6.1 in the 222K/K samples (n = 6), and the signal intensity of mAb F99/97.6.1 for PrP was lower for the 222Q/K samples (12/12 samples). To further investigate these results, additional Western blot analyses were performed, and the PrP signals detected by mAbs F99/97.6.1 and SAF84 were then quantified. The mean F99/SAF84 ratio (± standard deviation) calculated for the 222Q/Q group was 0.73 ± 1.26, and the mean for the 222Q/K group was 0.27 ± 1.31. Statistical analysis of these values evidenced statistically significant differences between the 222Q/Q and 222Q/K samples. The results of the study thus revealed an inhibition by lysine at position 222 on the binding of mAb F99/97.6.1 to goat PrP. This has implications for the use of mAb F99/97.6.1 for diagnostic purposes. Because the 222K allele could be a target for genetic selection in goats, the differential reactivity of mAb F99/97.6.1 could be exploited with a genotyping test setup.
朊病毒蛋白（PrP）由PRNP基因编码，该基因在山羊中具有高度多态性，其多态性在蛋白质水平上编码氨基酸替换。在本研究中，研究了单克隆抗体（mAb）F99/97.6.1与PRNP密码子222处多态性的山羊PrP结合的反应性。使用单克隆抗体P4和F99/97.6.1通过蛋白质印迹法分析了30只具有3种不同基因型（222Q/Q、222Q/K和222K/K）的瘙痒病阴性山羊的神经组织。虽然单克隆抗体P4在所有30个样本中都检测到了PrP，但单克隆抗体F99/97.6.1对PrP的检测仅限于222Q/Q（12/12）。在222K/K样本（n = 6）中，单克隆抗体F99/97.6.1未检测到PrP，并且对于222Q/K样本（12/12个样本），单克隆抗体F99/97.6.1对PrP的信号强度较低。为了进一步研究这些结果，进行了额外的蛋白质印迹分析，然后对单克隆抗体F99/97.6.1和SAF84检测到的PrP信号进行了定量。222Q/Q组计算的平均F99/SAF84比值（±标准差）为0.73±1.26，222Q/K组的平均值为0.27±1.31。对这些值的统计分析证明222Q/Q和222Q/K样本之间存在统计学上的显著差异。因此，该研究结果揭示了222位赖氨酸对单克隆抗体F99/97.6.1与山羊PrP结合的抑制作用。这对将单克隆抗体F99/97.6.用于诊断目的具有影响。由于222K等位基因可能是山羊遗传选择的目标，单克隆抗体F99/97.6.1的差异反应性可通过基因分型测试设置加以利用。
