Outer membrane vesicles (OMV) production of Neisseria meningitidis serogroup B in batch process

Abstract

Serogroup B outer membrane vesicles (OMV) with iron regulated proteins (IRP) from Neisseria meningitidis constitute the antigen for the vaccine against the disease caused by this bacterium. Aiming to enhance final OMV concentration, seven batch experiments were carried out under four different conditions: (i) with original Catlin medium; (ii) with original Catlin medium and lactate and amino acids pulse at the 6th cultivation hour; (iii) with Catlin medium with double initial concentrations of lactate and amino acids and (iv) Catlin medium without glycerol and with double initial concentrations of lactate and amino acids. The cultivation experiments were carried out in a 7-L bioreactor under the following conditions: 36°C, 0.5atm, overlay air 1L/min, agitation: 250-850 rpm, and O(2) control at 10%, 20 h. After lactate and amino acids exhaustion, cell growth reached stationary phase and a significant release increase of OMV was observed. According to the Luedeking & Piret model, OMV liberation is non-growth associated. Glycerol was not consumed during cultivation. The maximum OMV concentration value attained was 162 mg/L with correspondent productivity of 8.1mg/(Lh) employing Catlin medium with double initial concentrations of lactate and amino acids. The obtained OMV satisfied constitution and protein pattern criteria and were suitable for vaccine production.

Outer membrane vesicles as platform vaccine technology

“…Most early publications connect OMV formation with cell growth, since bleb formation was not observed in the stationary phase [87, 88], and cells growing at exponential phase produced more OMVs [79, 89]. The pattern is now mixed, with higher release of OMVs during late culture phase reported for N. meningitidis [90] and Francisella [91], while Salmonella typhimurium [73, 92], Borrelia [93], and Gallibacterium [94] seem to produce more vesicles during exponential growth. For H. pylori the release of OMVs is inversely related to the cell growth and is also correlated with shape transitions of the bacterium from spiral to coccoid [22].…”

“…The detergent D‐OMVs, are extracted from cells with detergent which also reduces the content of reactogenic LPS. The term native N‐OMV is used for intact spontaneous OMVs from cell supernatant [40], as well as for OMVs that are generated from concentrated dead cells with non‐detergent cell disruption techniques [90, 112]. Here, native N‐OMV will be used for vesicles extracted from cells with detergent–free methods, in accordance with previous nomenclature, and to be able to clearly distinguish them from the wild‐type spontaneous OMVs and the detergent‐extracted OMVs.…”

Polysaccharide Production in Pilot Scale Bioreactor Cultivations of Neisseria meningitidis Serogroup C

“…Santos et al [40, 41] studied the consumption of aminoacids in Catlin defined medium during batch process of N. meningitidis B and observed that L-lactate and L-glutamic were the main limiting carbon and nitrogen source, respectively. The L-glutamic acid consumption contributed to the formation of ammonia and the increase of pH during in cultivations and L-cysteine.HCl had small consumption.…”

Comparação entre Neisseria meningitidis e Neisseria lactamica: cinética do cultivo e potencial antigênico de OMV e frações.

“…Foram escolhidas neste trabalho as condições de cultivo e os meios de cultura que obtiveram melhores resultados de biomassa e concentração de OMV, em cultivo descontínuo, com base em trabalhos desenvolvidos anteriormente (GONÇALVES, 2012;SANTOS et al, 2012) Destaque em cinza para os valores máximos de DO 540nm e OMV.…”