| Popis: |
The study of cell surface glycosylation has increasingly been seen to be an important area in recent years. A cells ability to carry out its specific function hinges on its ability to correctly glycosylate its surface proteins. The cell membrane has a large number of embedded surface glycoproteins. Correct glycosylation is imperative for correct protein folding to facilitate a number of cellular processes, including; cell-cell signalling and cell adhesion. Alterations to these cell surface glycans can have detrimental effects for the cell and lead to a change in certain cellular functions. It is also recognised that changes in cell surface glycosylation are early indicators of the cell becoming stressed or diseased. To date, antibody probes are primarily utilised to interogate the surface of a cell, usually recognising surface proteins. However, this strategy has not worked for the study of surface glycosylation as antibodies are unable to recognise and distinguish between neutral glycans. Therefore, in order to understand the specific changes to the cell surface glycosylation, new technologies, including new probes, need to be explored and expanded to identify possible changes as accurately as possible. This work aimed to develop and modify a number of recombinant lectin probes that could be used in unison with commercially available eukaryotic lectin probes to interrogate the cell surface glycosylation of two colorectal carcinoma cell lines. In cancer cells, altered glycosylation is believed to be amongst the earliest changes to occur. These changes could also indicate the specific stages of certain cancers and infer if a cancer is metastasising or not. This work also reports on the use of a panel of lectins, in combination with flow cytometry and fluorescent microscopy, to identify glycosylation changes between an SW480 and SW620 cell line. These paired cell lines are from the same patient with SW480 classed as non-metastatic and SW620 classed as metastatic. This work shows a significant change in the levels of sialylation, both in type and abundance, between the two different cell lines. With a decrease in lectin binding for sialic acid, there was a proportional increase in galactophilic lectin binding which highlights the altered glycosylation found on the cell surface of these cell lines. |
