The Study On Natural Antibody 3B4 Againist Interreaction Of Candida Albicans To Host Cell In Vitro

The designation of natural antibodies (NAbs) is given to antibodies, circulating in normal individuals, they are encoded by germline gene in the absence of overt specific antigenic stimulation, aim at one and/or many kinds of exogenous antigen, and their character include: multiple reactance and low affinity. Since the discovery of NAbs, a series of research of its function have been carried out, and the result indicate: NAbs are the important part for the construction of natural imuune system, further more, they play an important role in oncological surveillance, autoimmunity, variant rejection, anti-infection, etc.In recent years, as antibiotics, corticosteroid hormone, immune depressant are widely used, increasing number of HIV infected person, development of heteroplasty, high tumor incidence, and the fungous infection is significantly upgraded, especially for the Candida albicans, human became generally realized that humoral immunity plays an important role in anti-fungous infection, also, natural humoral immunity is the first line of defense for human to resist external infection. The function of natural antibody generally caused attention, however there are some facts indicate natural antibody may have capacity of anti-fungous infection, despite lacing of direct evidence.Our topic group is supported by National Natural Science Foundation of China (30330510,30300318, 30330550, 30425015), we applied non immuned B cell to fuse with myeloma cell, and got 3 strains of hybridoma cell which can secrete natural antibody IgM successfully. Theirs variable region gene are highly homologisation with germline gene, especially for the natural antibody IgM 3B4, its binding activity with antigen is the best, and it is verified that natural antibody IgM 3B4 can regulate the phagocytosis of phagocyte for staphylococcus aureus, and natural antibody IgM 3B4 can combine with glucoprotein of Candida albicans's sporoderm. Based the earlier work, our research apply natural antibody IgM 3B4 obtained by purification, aim at Candida albicans, to investigate the effectiveness of natural antibody IgM 3B4.Using natural antibody IgM 3B4, our research have proved in vitro that:â—‹1 It was found that the different concentrations of natural antibody IgM 3B4 could inhibit Candida albicans germ tube formation in vitro;â—‹2 It was found that the natural antibody IgM 3B4 could inhibit the adherency of Candida albicans to host cell in vitro;â—‹3 Using ELISA and RT-PCR, we have investigated the effectiveness of natural antibody IgM 3B4 on the expression and secretion of IL-6,IL-8,IVAM-1,VCAM-1 of vascular endothelial cell of allantoic veins which infected by Candida albicans, and we discovered that IgM 3B4 significantly improved the expression and secretion of above-mentioned cytokine of vascular endothelial cell of allantoic veins. In conclusion, we have proved that natural antibody IgM 3B4 has capacity of resisting infection of Candida albicans in vitro,the capacity of resisting infection have relation with inhibiting Candida albicans germ tube formation, inhibiting the adherency of Candida albicans to host cell and improving the expression and secretion of IL-6,IL-8, ICAM-1,VCAM-1 of vascular endothelial cell of allantoic veins .