Day 10

Today we were doing some cell biology with Mulu, an associate researcher who did her post doc on molecular and cellular biology. One project she is working on is the testing of drugs designed to promote the differentiation of muscle cells to in order to treat duchenne muscular dystrophy. We got to see pictures of muscle cells that had been stained with different antibodies in order to identify their components, e.g the nuclear and tubulin proteins by using different stains that contain antibodies that bind to specific proteins. The different components of the cell are then displayed on the screen by applying a specific wavelength of light to the sample which interacts with the antibody stain. This technique can be used to visually determine the efficacy of different drugs of varying concentrations by displaying the degredation of proteins in response to the treatment. Below is an image of the microtubules in a muscle cell, which are a major component of the eukaryotic cytoskeleton.

We then learnt how the drugs created by the organic chemists were tested on cancer cells in order to determine their efficacy. The aim of the investigation was to determine the optimum concentration of the drugs that were designed to kill leukemia cells. We watched as Mulu prepared a linear dilution series of the drug by adding different volumes of growth serum to the pure drug. Several repeats were carried out for the different drug concentrations of each drug to improve reliability. A negative control was also added to ensure that no other factors other than the independent variable affected the dependant variable (the effect of the drug on the cell). Leukemia cells are non adherent, meaning they do not multiply to form clumps such as tumors in breast cancer, which are known as adherent cells. This means that the leukemia can be grown in liquid medium as opposed to an agar plate. We found it fascinating to learn about how the toxicity of drugs is determined and how cell lines are cultured indefinitely.

We were then picked up by Mr Markwell, who kindly took us for a car tour through the town of Mississauga on the way back to downtown Toronto. After stopping for lunch, we went to a mall to check out the local shops, before we went to see a screening of ‘Booksmart’ (a feel good comedy) at the cinema. We all really enjoyed it, it was a great end a lovely day.