Bacterial Ghosts of Pseudomonas aeruginosa as a Promising Candidate Vaccine and Its Application in Diabetic Rats

Abstract

Infections with Pseudomonas aeruginosa (PA) pose a major clinical threat worldwide especially to immunocompromised patients. As a novel vaccine network for many kinds of bacteria, bacterial ghosts (BGs) have recently been introduced. In the present research, using Sponge-Like Reduced Protocol, P. aeruginosa ghosts (PAGs) were prepared to maintain surface antigens and immunogenicity. This is the first study, to our knowledge, on the production of chemically induced well-structured bacterial ghosts for PA using concentrations of different chemicals. The research was carried out using diabetic rats who were orally immunized at two-week intervals with three doses of PAGs. Rats were subsequently challenged either by the oral route or by the model of ulcer infection with PA. In challenged rats, in addition to other immunological parameters, organ bioburden and wound healing were determined, respectively. Examination of the scanning and transmission electron microscope (EM) proved that PAGs with a proper three-dimensional structure were obtained. In contrast to control groups, oral PAGs promoted the generation of agglutinating antibodies, the development of IFN-γ, and the increase in phagocytic activity in vaccinated groups. Antibodies of the elicited PAGs were reactive to PA proteins and lipopolysaccharides. The defense against the PA challenge was observed in PAGs-immunized diabetic rats. The resulting PAGs in orally vaccinated diabetic rats were able to evoke unique humoral and cell-mediated immune responses and to defend them from the threat of skin wound infection. These results have positive implications for future studies on the PA vaccine.

Production and Evaluation of the Immunogenicity of an Enterobacter aerogenes Ghost Vaccine in a Mouse Model

“…Our results showed the correct preparation of EAGs using the SLRP method. They agreed with [30]which used the same method to prepare bacterial Ghosts of Pseudomonasaeruginosa.…”

“…The protocol is capable of producing ghosts from a variety of microorganisms, such as gram-positive, gramnegative, capsulated, sporeforming bacteria, viruses, and eukaryotic cells. It has gained widespread acceptance due to its cost-effectiveness, reliability, and versatility with a wide range of microorganisms [30,31,32].…”

Pseudomonas aeruginosa: Recent Advances in Vaccine Development

“…They are generated from Gram-negative bacteria by inducing release of their intracellular contents, resulting in an empty preserved bacterial envelope with intact surface antigens and PAMPs [ 114 ]. In the first study of its kind, Sheweita et al developed chemically-induced BGs to vaccinate diabetic rats against P. aeruginosa [ 115 ]. Orally administered BGs induced a specific humoral and cell-mediated immune response.…”