Heterologous expression and immunological reactivity of the recombinant lipoprotein GUDIV-517 from Ureaplasma...

Ureaplasma diversum infects cattle and plays a significant role in economic losses in the livestock sector, as it is associated with the development of reproductive and respiratory disorders in these animals. Studies have suggested that membrane-associated lipoproteins (LAMPs) are closely linked to the pathogenicity of these bacteria. Thus, this study aimed to express the lipoprotein GUDIV-517 from U. diversum (rGUDIV-517) in a heterologous system and evaluate the immunogenicity of this antigen in cultured bovine peripheral blood mononuclear cells (PBMC). The vector pET-28a (+) containing the gene sequence gudiv-517 was expressed in Escherichia coli BL21(DE3). The recombinant protein was inoculated into mice (BALB/c) to produce anti-rGUDIV-517 antibodies. Indirect ELISA verified immunogenicity. Quantification of nitric oxide (NO) and Hydrogen peroxide (H₂O₂₎ was performed in the PBMC culture supernatant, and expression analysis of IL-1β, TNF-α, TLR2, TLR4, iNOS, and caspase-3 genes was conducted by quantitative PCR (qPCR). This study demonstrated that booster doses of rGUDIV-517 induce increased IgG production and avidity. Recombinant GUDIV-517 also induced an upregulation of the immune response, characterized by increased H₂O₂ and NO production, as well as the expression of pro-inflammatory markers, in PBMC culture compared to the negative control. All these data make rGUDIV-517 a promising target for diagnostic tests and vaccine development against U. diversum.