|
Journals
Author(s):
|
Csordas FCL, Perciani CT, Darrieux M, Goncalves VM, Carbrera-Crespo J, Takagi M, Sbrogio-Almeida ME, Leite LCC, Tanizaki MM
|
Journal:
|
Protection induced by pneumococcal surface protein A (PspA) in enhanced by conjugation to a Streptococcus pneumoniae capsular polysaccharide
|
Volume:
|
Vaccine, 26, 2925-2929
|
Year:
|
2008
|
Abstract:
|
The currently available anti-pneumococcal vaccines are based on capsular polysaccharide (PS), plain or conjugated to a carrier protein. Conjugated vaccines are expensive products, especially in the case of pneumococcus, in which reasonable coverage requires from 7 to 13 serotypes. To obtain increased coverage with fewer components, we evaluated the immunogenicity of the pneumococcal surface protein A (PspA), conjugated to capsular polysaccharide serotype 23F, aiming at induction of an immune response against both components. Mice immunized with PS23F-rPspA1 conjugate produced antibodies against both PS and rPspA1, comparable or slightly higher than that obtained by free PS. The immunized animals challenged with a lethal dose of a virulent strain bearing a homologous PspA, showed that the PS23F-rPspA1 conjugate induced higher survival than rPspA1 alone or in combination with PS. This increased protection was shown to correlate with the enhanced capacity of the antibodies to bind to the pneumococcal surface and to induce complement deposition. Our results indicate that the use of PS-PspA conjugates may be a way to increase coverage against pneumococci with fewer components.
|
Address of Author(s):
|
Instituto Butantan, Centro de Biotecnologia, Av. Vital Brasi 1500, 05503-900 Sao Paulo, SP, Brazil
|
Contact(s):
|
» Contact (E-Mail)
|
Download:
|
n/a
|
|
Author(s):
|
Rodrigues, M T A, Vilaca, P R, Garbuio, A, Takagi, M, Barbosa Jr., S, Léo, P, Laignier, N S, Silva, A A P, Moro, A m
|
Journal:
|
Glucose uptake rate as a tool to estimate hybridoma growth in a packed bed bioreactor
|
Volume:
|
Bioprocess Engineering, 21, 543-546
|
Year:
|
1999
|
Abstract:
|
The immobilisation of cells in a perfusion culture allows to obtain a high cell concentration and an efficient removal of the catabolites without cell loss. A disadvantage of this system is that the cell density cannot be directly monitored. The cellular metabolism is just followed by online measurements of pH and dissolved oxygen (DO) and off-line determinations of residual metabolites. In this article, we report a high cell density achieved by the cultivation of a hybridoma in a bubblecolumn bioreactor filled with hollow glass cylinders. The parameters monitored during the cultivation were pH, temperature, DO, glucose, lactate and monoclonal antibody. The glucose uptake rate was used to estimate the cell concentration along the time. The maximum cell concentration calculated for the considered cultivation time was
2.7 x 107 cell • ml-1. The glucose concentration in the media decreased stepwise twice, causing a decrease on the specific growth rate, while maintaining high antibody productivity levels. Maximum monoclonal antibody productivity was 503 ?g • l-1 • day-1 and specific productivity, considering calculated cell density, was 0.019 ng • cell-1 • day-1.
|
Address of Author(s):
|
Instituto Butantan, Centro de Biotecnologia, Av. Vital Brasi 1500, 05503-900 Sao Paulo, SP, Brazil
|
Contact(s):
|
» Contact (E-Mail)
|
Download:
|
n/a
|
|
|
|
|
Like to be listed
in one of our categories?
Please » contact us.
- Space for ads -
|
