RESUMO
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.
Assuntos
Proteínas da Membrana Bacteriana Externa/biossíntese , Reatores Biológicos , Neisseria meningitidis Sorogrupo B/metabolismo , Vesículas Secretórias/química , Aminoácidos/química , Técnicas de Cultura Celular por Lotes , Meios de Cultura/química , Glicerol/metabolismo , Proteínas Reguladoras de Ferro/química , Ácido Láctico/química , Vacinas Meningocócicas/biossínteseRESUMO
Renal cell carcinoma (RCC) is one of the most lethal urologic cancers and is highly resistant to both radiotherapy and chemotherapy. The recombinant protein Amblyomin-X, characterized as a Kunitz-type protease inhibitor, was obtained from a cDNA library from the salivary glands of the Amblyomma cajennense tick. This paper reports the biological effect of Amblyomin-X on inducing cell death by apoptotic process in vitro. For this purpose, the changes in morphological aspects of cells, the phosphatidylserine exposition and DNA degradation were evaluated after treatment with Amblyomin-X. We found that Amblyomin-X was able to induce apoptosis in Renca cells in a dose-dependent manner. So, the results presented here open perspectives for new researches and developing for Amblyomin-X in the treatment of RCC.