Inhibition of Acinetobacter baumannii adhesion to human lung epithelial cells by antibody produced against Omp۳۴

BACKGROUND AND OBJECTIVESAcinetobacter baumannii causes infections such as meningitis, bloodstream infections, pneumonia, urinary tract and skin infections in hospitals, especially in intensive care units. The interaction between A. baumannii and human lung cells leads to infection and cell death due to adhesion and invasion of these cells. Therefore, it is important to study the interaction of A. baumannii with human lung host cells. Outer membrane protein ۳۴ )Omp۳۴) is one of the virulence factors of A. baumannii. Cytotoxicity, adhesion, and attack on human epithelial cells, as well as induction of apoptosis and inhibition of autophagy in human cells, are among the functions of this main pathogenic agent. In-vitro cell culture methods are a useful tool for investigating the interactions between human epithelium and pathogens that occur during infection because bacterial adhesion to cells is considered to be the first major step in bacterial pathogenesis. In this study, A. baumannii ATCC ۱۹۶۰۶ and a clinical isolate, A. baumannii ۵۸ST were analyzed in terms of adhesion and internalization to A۵۴۹ cell line.MATERIALS AND METHODSrOmp۳۴ was expressed, purified, and injected into groups of BALB/c mice. The antibody titer was measured by the indirect ELISA. Adhesion and internalization of A. baumannii strains were studied in A۵۴۹ cell line.RESULTS AND DISCUSSIONOmp۳۴, a conserved and potent immunogen of A. baumannii, significantly inhibited adhesion to and internalization in A۵۴۹ cells of A. baumannii strains.CONCLUSIONAntibodies raised to Omp۳۴ prevent bacterial adhesion and invasion of A۵۴۹ lung cells.

Keywords:

Acinetobacter baumannii , Omp۳۴ , A۵۴۹ , Adherence