抗白念珠菌芽管单克隆抗体的制备及特性鉴定

目的制备抗白念珠菌芽管的单克隆抗体mAb03.2C1-C2,并对其特性进行分析,以探讨其应用于实验室检测的可行性。方法利用杂交瘤技术制备分泌抗白念珠菌芽管胞壁外膜抗原mAb的杂交瘤细胞株,对mAb的Ig亚类进行鉴定。用间接免疫荧光(IIF)法对mAb的抗体活性及特异性进行测定。在白念珠菌芽管形成条件下,加入mAb,观察其对白念珠菌芽管诱导的抑制及白念珠菌对上皮细胞、内皮细胞黏附的抑制。复苏冻存的杂交瘤细胞株,分析其持续分泌mAb的能力。结果获得1株mAb03.2C1-C2,其Ig亚类为IgG1。该mAb仅与白念珠菌芽管特异性结合,并能显著降低白念珠菌芽管的生成率以及在芽管形成条件下对上皮细胞、内皮细胞的黏附,其抑制作用与该mAb的浓度呈正比。结论制备的mAb03.2C1-C2抗体效价高,在体外能抑制白念珠菌芽管的形成,降低白念珠菌的侵袭力。而且其对白念珠菌芽管具有高度的特异性,可用于白念珠菌和都柏林念珠菌的快速鉴别。

Prepare and study on the characterization of a new monoclonal antibody to germ tube Candida albicans

AIM: To prepare and identify the monoclonal antibody(mAb) specific for the germ tube of Candida albicans. METHODS: mAb were prepared via hybridoma technique. Indirect immunofluorescence (IIF) was used to analyze the activity and specificity of the mAb. The protection of the mAb was analyzed via the inhibition of the mAb to the germ tube formation and the adhesion of C.albicans to the epithelial and endothelial cells. The frozen hybridoma cells were cultured to analyze the ability of the secretion of the mAb. RESULTS: mAb03.2C1-C2 belongs to IgG1 subclass. Relative molecular mass(M_r) of antigens recognized by the mAb was 156, 48, 22 and 12. The target antigen could be detected 30 minutes after the germ tube formation. The epitope might lie in the N-carbohydrate chain. mAb03.2C1-C2 was shown by IIF test to be specific to the surface of the germ tube or mycelium phase of C. albicans. In the protective mAb screening experiment, it was found that mAb3.2C1-C2 could inhibit C.albicans germ tube formation and the adhension of C.albicans to the epithelial and endothelial cells. CONCLUSION: In vitro, mAb03.2C1-C2 could inhibit the formation of germ tube of C.albicans, which could depress the invasiveness of C.albicans. This anti-C.albicans cell wall surface-specific mAb may be a good candidate for use in tests for the rapid differentiation of the two closely related species C.albicans and C.dubliniensis.