Cronobacter sakazakii is a foodborne pathogen associated with rare but often lethal infections in neonates. Powdered infant formula (PIF) represents the most frequent source of infection. Out of the identified serotypes (O1 to O7), O1, O2, and O3 are often isolated from clinical and PIF samples. Serotype-specific monoclonal antibodies (MAbs) suitable for application in enzyme immunoassays (EIAs) for the rapid detection of C. sakazakii have not yet been developed. In this study, we created specific MAbs with the ability to bind to C. sakazakii of serotypes O1, O2, and O3. Characterization by indirect EIAs, immunofluorescence, motility assays, and immunoblotting identified lipopolysaccharide (LPS) and exopolysaccharide (EPS) as the antigenic determinants of the MAbs. The established sandwich EIAs were highly sensitive and were able to detect between 2 ؋ 10 3 and 9 ؋ 10 6 CFU/ml. Inclusivity tests confirmed that 93% of serotype O1 strains, 100% of O2 strains, and 87% of O3 strains were detected at low cell counts. No cross-reactivity with >100 strains of Cronobacter spp. and other Enterobacteriaceae was observed, except for that with C. sakazakii serotype O3 and Cronobacter muytjensii serotype O1. Moreover, the sandwich EIAs detected C. sakazakii in PIF samples artificially contaminated with 1 to 10 bacterial cells per 10 g of sample after 15 h of preenrichment. The use of these serotype-specific MAbs not only allows the reliable detection of C. sakazakii strains but also enables simultaneous serotyping in a simple sandwich EIA method. Cronobacter spp. are Gram-negative opportunistic foodborne pathogens of the family Enterobacteriaceae that cause rare but severe infections in patients of all age groups. In adults, Cronobacter spp. are often associated with nosocomial infections, including pneumonia, septicemia, wound infections, and osteomyelitis, while causing invasive disease in young infants and neonates (1-4). Among the seven identified Cronobacter species, C. sakazakii, C. malonaticus, C. muytjensii, C. turicensis, C. dublinensis, C. condimenti, and C. universalis (5-8), C. sakazakii plays a prominent role due to it causing life-threatening infections in neonates (9-11). Clinically manifested infections present as necrotizing enterocolitis, sepsis, and meningitis, with a mortality rate as high as 80% (1, 12, 13). Although C. sakazakii has been isolated from a variety of different plant-and animal-based food products (14, 15), the presence in powdered infant formula (PIF) seems crucial in the infection of neonates (9, 12, 16). According to an established O-antigen serotyping scheme based on rabbit antisera and a PCRbased serotyping method (17-21), seven serotypes (O1 to O7) have been identified for C. sakazakii. Serotypes O1 and O2 seem to be most prevalent in PIF samples and in clinical cases, whereas serotype O3 has been isolated quite frequently from PIF but not as often from clinical cases (19,(22)(23)(24).Today, the contamination of PIF by C. sakazakii is being detected using conventional microbiological m...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.