Allergies represent a dysfunction in the activity of the immune system and are affecting increasingly more people nowadays. There are different ways of treating these diseases, but these ways are often demanding, have serious side effects, are unpleasant for the patient and not necessarily successful. Due to these reasons, researchers are trying to find new therapy choices. Short chain peptides show a great potential – these are mimotopes, which can mimic allergens and bind with the antibodies IgE of a patient, but do not cause an allergic reaction and in time can appease an allergic reaction. For this master thesis we have chosen mimotopes that mimic the main allergen of peanuts, since peanut allergy is one of the most common allergies. We have used lactic acid bacteria as carriers – strain Lactococcus lactis, which are considered as useful bacteria and are extensively researched. The aim of this master thesis was to prepare transformed lactic acid bacteria that have the ability of surface expression of mimotopes that mimic the allergen of peanuts and bind with the antibodies IgE. Bacteria Lactococcus lactis have been transformed with plasmids, which carried the genes for the chosen peptides – mimotopes - by the process of electroporation. Prior to that process, we have replicated their genes in bacteria Escherichia coli. The success of the transformation was checked/tested with the affirmation of the right sequence of nucleotides for the chosen peptides in the bacteria, while the success of the expression and functionality of peptides was tested with the enzyme-linked immunosorbent assay (ELISA) and the western blot. In the experimental part, we have achieved the set goal – the process of transformation was successful, since the bacteria expressed the peptides on their surface. That was proven with the right sequences of the entered genetic code, while western blot proved the presence of peptides on the surface of L.lactis. In addition, by using the human serum of the patients with allergies and western blot we have proven the fact that peptides are indeed mimotopes. We can then conclude that peptides have a great potential and hope that further research will bring new and improved medicine for allergies.
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