抗人白细胞单克隆抗体的特异性及其特性鉴定

Preparation and characterization of monoclonal antibody against human leukocytes

目的制备抗人白细胞单克隆抗体（ｍＡｂ），并对其识别抗原及组织的特异性进行鉴定。方法采用分离的人全白细胞悬液免疫Ｂａｌｂ／ｃ小鼠，取脾细胞与Ｓｐ２／０细胞常规融合，用间接ＥＬＩＳＡ筛选ｍＡｂ，流式细胞仪及免疫组化染色ＳＰ法鉴定其组织特异性。 结果成功地制备１株抗人白细胞 ｍＡｂ，命名为ＳＺ－１０５。ＥＬＩＳＡ法测定其腹水效价为１×１０－５。琼脂糖双扩散鉴定为ＩｇＧ１类。流式细胞仪间接免疫荧光技术及免疫组化ＳＰ法测定表明，ｍＡｂ ＳＺ－１０５可选择性地与外周血液的粒细胞、单核细胞和淋巴细胞呈强阳性反应，而与红细胞及血小板不出现反应。该ｍＡｂ还可与正常人骨髓的白细胞前体起反应。另外，在肝、肺、脾、胸腺及淋巴结正常组织中的巨噬细胞表面，也有ＳＺ－１０５抗原表达。ＳＺ－１０５抗原经亲和层析纯化，再经ＳＤＳ－ＰＡＧＥ 和Ｗｅｓｔｅｒｎ ｂｌｏｔ证实，ｍＡｂ ＳＺ－１０５识别的抗原是相对分子质量（Ｍｒ）为７５ ０００左右的单链蛋白多肽。结论 获得１株具有高度免疫学活性和组织特异性的抗人白细胞ｍＡｂ ＳＺ－１０５，其对研究白细胞的分化、免疫功能，以及隐匿性急、慢性炎症疾病的放免显像诊断都具有一定的临床意义。

Aim To prepare monoclonal antibody(mAb)against human leukocytes and identify its tissue and antigen-recognizing specificity.Methods Balb/c mice was immunized with humanleukocytic suspension. The immunized spleen cells and the Sp2/0 myeloma cells were conventionally fused. The mAbs were screened by indirect ELISA and the tissue specificity of mAbs was identified by flow cytometry and immunohistochemical SP staining. Results One mAb SZ-105 against human leukocytes was obtained. The titer of mAb SZ-105 in ascites was 1×10-5.Its Ig subclass was IgG1. Flow cytometry and immunohistochemical SP staining showed that mAb SZ-105 could react selectively to human granulocytes, monocytes,lymphocytes , and their bone marrow precursors, while not reeognizing platelets and ery-throcytes.In addition, SZ-105 antigen was expressed on the macrophage from liver,lung, thymus, spleen and lymph node.The antigen recognized by mAb SZ-105 was purified by affinity chromatography. and proved to be a singlechain protein with, having a M rof 75 000, by SDS-PAGE and Western blot. Conclusion Preparation of a mAb SZ-105 against leukocytes with higher immuno-activity and tissue specificity will be of certain value to the studies on leukocyticdifferentiation and immunologic function and will also provide a effective approach for the radioimmunoimaging diagnosis of clinically latent acute or chronic infectious diseases.