Soluble interleukin-2 receptor (sIL-2r) is released directly from the surface of lymphocytes expressing interleukin-2 receptor alpha chain (CD25), and its serum concentration has been found to reflect the prognosis of human lymphoproliferative malignancies. In this study, we demonstrated the presence of sIL-2r in canine serum and developed a specific sandwich enzyme-linked immunosorbent assay (ELISA) to quantify the concentration of canine serum sIL-2r. In the immunoprecipitation (IP) assay, CD25 protein weighing approximately 45 kDa was detected in canine serum, smaller than the membrane-bound CD25 (approximately 55 kDa). To measure the concentration of serum sIL-2r in dogs, an ELISA system was developed. Serum sIL-2r levels were significantly higher in dogs with multicentric high-grade B-cell lymphoma before therapy than that in healthy dogs. Serum sIL-2r concentration was also found to be elevated in a proportion of dogs with other types of lymphoma. Changes in serum sIL-2r levels generally paralleled the changes in mass and lymph node size in dogs with high-grade B-cell lymphoma. This study demonstrated that serum sIL-2r level would be a marker to monitor tumour growth and regression in canine lymphoma.

中文翻译：

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淋巴瘤犬血清可溶性白介素2受体α链浓度的测量。

可溶性白介素2受体（sIL-2r）从表达白介素2受体α链（CD25）的淋巴细胞表面直接释放，其血清浓度已反映出人类淋巴增生性恶性肿瘤的预后。在这项研究中，我们证明了犬血清中sIL-2r的存在，并开发了一种特异性的夹心酶联免疫吸附测定（ELISA）来定量犬血清sIL-2r的浓度。在免疫沉淀（IP）分析中，在犬血清中检测到重约45 kDa的CD25蛋白，小于膜结合的CD25（约55 kDa）。为了测量狗中血清sIL-2r的浓度，开发了ELISA系统。治疗前多中心高级别B细胞淋巴瘤犬的血清sIL-2r水平明显高于健康犬。在患有其他类型淋巴瘤的狗中，也发现血清sIL-2r浓度升高。血清sIL-2r水平的变化通常与高度B细胞淋巴瘤犬的质量和淋巴结大小变化平行。这项研究表明血清sIL-2r水平将成为监测犬淋巴瘤中肿瘤生长和消退的标志物。