Commercial media and surfaces for cell cultivation do not promote conditions for cell cultivation and proliferation with specific interactions cell-material surface. The aim of this thesis is developing surfaces for cell cultivation which mimic conditions in living tissues. The approach introduced in this thesis is based on applying biomimetic peptide ligands on inert supporting materials with non-fouling properties. Considering that a choice of a ligand sequence and distance between peptides can dramatically influence the outcome, a few model peptides with varying parameters were synthesized and investigated. The cell adhesive peptides were synthesized by solid phase peptide synthesis and scrambled peptides were synthesized and tested as well. Spatial deposition of peptides is another highly important point of study. The 'click'- reaction was used to successfully immobilize the peptides on produced surfaces. The distance between the peptide molecules on the surfaces was controlled by their concentration in a reaction mixture. The reference samples were immobilized with radiolabeled peptides for quantitative estimation of the peptides present. Then, the materials with different types of peptides and range of concentrations were examined via cultivation of cell cultures. The experiments were focused on...

This master’s thesis contains a description of mesenchymal stem cells (MSC). The work includes knowledge about the process of migration and differentiation of MSCs. The theoretical part of this thesis also deals with the problem of cell cultivation in 2D and 3D environments. The most used materials for creating 3D scaffolds are described here. The practical part contains the description of the cell culture protocol for passaging and also describes the experiment in the cell laboratory. The results of the experiment are discussed using confocal microscope images. The proposed experiment was tested with a sufficient number of repetitions. The processing of microscopic images was performed in the MATLAB programming environment.

Made available in DSpace on 2016-06-02T19:56:54Z (GMT). No. of bitstreams: 1 5933.pdf: 2457795 bytes, checksum: b5b6653a532bc7e6c4a9ec2685b55277 (MD5) Previous issue date: 2014-08-15 / Universidade Federal de Minas Gerais / Owing to the broad biochemical, physiological and genetic characterization and the ease of manipulation and cultivation, several proteins with therapeutic and industrial applications are produced by genetically modified Escherichia coli. There is abundant information in the literature about strategies to increase biomass and recombinant protein production by cultivation of E. coli employing stirred and aerated tank bioreactor (conventional type). In contrast, although quite employed in cultivation of filamentous microorganisms, there are just a few studies involving cultivation of E. coli in airlift bioreactor. This reactor offers advantages over conventional one, such as simplicity of construction, reduced risk of contamination and efficient gas-liquid dispersion with low power consumption. However, the lower O2 transfer in airlift bioreactor (bench scale), compared to that achieved in conventional one, justifies the manipulation of temperature, pressure and flow rates of air and O2 in the dissolved oxygen concentration (DOC) control, avoiding decreases in biomass and recombinant protein productivities. In this context, this study aimed to: (i) determine the influence of internal pressure on the gas holdup (ɛ), volumetric O2 transfer coefficient (kLa) and volumetric O2 transfer rate (continue...). / Devido à ampla caracterização bioquímica, fisiológica e genética e à facilidade de manipulação e de cultivo, diversas proteínas com aplicação industrial e terapêutica são produzidas por Escherichia coli geneticamente modificada. Há informações abundantes na literatura sobre estratégias para aumentar a produção de biomassa e de proteínas recombinantes por meio de cultivos de E. coli empregando biorreator tipo tanque agitado e aerado (convencional). Por outro lado, apesar de bastante empregado em cultivos de microrganismos filamentosos, poucos trabalhos envolvendo cultivo de E. coli em reator pneumático tipo airlift são encontrados. Este biorreator apresenta vantagens frente ao convencional, como simplicidade de construção, menor risco de contaminação e eficiente dispersão gás-líquido com baixo consumo de energia. Entretanto, a menor capacidade de transferência de O2 no biorreator airlift em escala de bancada, em relação à alcançada em reator convencional, justifica a manipulação de variáveis como temperatura, pressão e vazões de ar e O2 no controle adequado da concentração de O2 dissolvido (COD), evitando quedas de produtividade de biomassa e de proteína recombinante. Nesse contexto, este trabalho objetivou: (i) determinar a influência da pressão interna sobre a retenção gasosa (ɛ), o coeficiente volumétrico de transferência de O2 (kLa) e a velocidade volumétrica de transferência de O2 (continua...).