Sturtevant J E, Latgé J P
Unité de Mycologie, Institut Pasteur, Paris, France.
Infect Immun. 1992 May;60(5):1913-8. doi: 10.1128/iai.60.5.1913-1918.1992.
Activation and deposition of C3 on Aspergillus fumigatus conidia have been previously demonstrated. This study investigated in further detail the interactions between complement component C3 and the conidia of A. fumigatus. Immunoblotting and 125I-C3 binding studies showed that C3 deposition was rapid (less than 15 min) and parallel to the formation of iC3b. Immunoblotting experiments identified a 54- to 58-kDa conidial protein which binds human complement component C3 and/or a C3 fragment(s). 125I labeling of the outer layer of the conidia demonstrated that this protein doublet was present on the surface of the spore. The further degradation of C3 to low-molecular-mass fragments (40, 37, and 30 kDa), in the absence of plasma, by intact living conidia and a preparation of the outer conidial wall layer indicated the ability of fungal components to cleave C3. These data suggest that interactions between conidia and C3 are not limited only to deposition via activation of the alternative complement pathway; they also include degradation of bound C3.
先前已证实C3在烟曲霉分生孢子上的激活和沉积。本研究进一步详细调查了补体成分C3与烟曲霉分生孢子之间的相互作用。免疫印迹和¹²⁵I-C3结合研究表明，C3沉积迅速（不到15分钟），且与iC3b的形成平行。免疫印迹实验鉴定出一种54至58 kDa的分生孢子蛋白，其可结合人补体成分C3和/或C3片段。分生孢子外层的¹²⁵I标记表明，这种蛋白双峰存在于孢子表面。在无血浆的情况下，完整的活分生孢子和分生孢子外壁层制剂将C3进一步降解为低分子量片段（40、37和30 kDa），这表明真菌成分具有裂解C3的能力。这些数据表明，分生孢子与C3之间的相互作用不仅限于通过替代补体途径激活进行沉积；还包括结合的C3的降解。
