Enhancing Cell Viability and Immunogenicity of OmpA as a Promising Subunit Vaccine Candidate Against Cytotoxic Effects of A. baumannii

BACKGROUND AND OBJECTIVESAcinetobacter baumannii is a significant opportunistic pathogen and a major concern in healthcare settings due to its involvement in nosocomial infections and high antimicrobial resistance. The alarming mortality rate among infected patients underscores its success as a pathogen. Outer membrane protein A (OmpA) has been identified as a crucial virulence factor associated with the survival and pathogenicity of A. baumannii. OmpA interacts with eukaryotic cells, leading to cytotoxicity by binding to death receptors on the cell surface. Additionally, OmpA plays a significant role in bacterial pathogenesis by interacting with epithelial cells, inducing apoptosis, and inhibiting complement activation.MATERIALS AND METHODSThe OmpA was expressed and purified. The purified protein was then injected into groups of mice to induce the production of anti-OmpA antibodies. HeLa cells were plated at ۷۰% confluency. The standard strain of A. baumannii ATCC ۱۹۶۰۶ and a clinical isolate, A. baumannii ۵۸ST, were exposed to Anti-OmpA serum. The cells were incubated with the bacteria-cell solution overnight. MTT test was performed.RESULTS AND DISCUSSIONOmpA was successfully expressed, purified, and visualized as ∼ ۳۸kDa on SDS-PAGE. An increased antibody titer was achieved as measured by indirect ELISA. Cells exposed to the sera showed lower infections than the control group.CONCLUSIONThe presence of anti-OmpA antibodies enhances cell viability against the cytotoxic effects of A. baumannii. OmpA demonstrates immunogenicity and holds promise as a candidate for the development of an effective subunit vaccine against A. baumannii infections.

کلیدواژه ها:

Acinetobacter baumannii ، OmpA ، Cytotoxic effects ، HeLa cell line ، Subunit vaccine