Cell Biology ADHESION WRITE UP Essay Example | Topics and Well Written Essays - 1500 words

Cell Biology ADHESION WRITE UP - Essay Example Cadherins are found as trans-membrane proteins (Rastogi, 2007). There are four main types of classical cadherins, with the epithelial cadherin playing an important role in the growth of tumours (Asano et al, 2004). Cells possessing cadherins generally adhere to other cells possessing cadherins. By exploring these cell adhesion mechanisms with an assay, it is possible to understand more fully the role of the intracellular matrix and the reactions which occur within it. The assay described below relies on the interesting effects that trypsin has on these cadherin molecules. In the presence of calcium and trypsin, the cadherins are protected from cleavage, but in the presence of a trypsin and EDTA mixture, the cadherins are removed from the cell surface and thus the cells stop aggregation. Results Trypsin is commonly used to detach the adhering cells (Humphries, 2001). Prior to the addition of trypsin, the cells were adhering to each other forming a suspended clump of cells within the w ells. However, after the trypsin was added, there was less evidence of adhesion and the cells were in the matrix singularly. After fixing, only the adhering cells were found in the well. This again gave a ‘clumped’ look to the cells. After viewing this, the wells were stained with methylene blue, and this the wells had a typical blue appearance in the top two rows, suggesting normal adhering cells were present. ... Raw Data 1 2 3 4 5 6 7 8 9 10 11 12 A 0.935 0.685 0.798 0.857 2.35 2.323 2.253 2.523 2.427 2.809 2.58 2.416 B 0.445 0.488 0.632 0.401 2.165 2.13 2.308 1.708 0.774 0.851 1.072 0.814 C 0.028 0.023 0.037 0.028 0.025 0.025 0.025 0.025 0.026 0.025 0.026 0.027 D 0.029 0.031 0.027 0.029 0.028 0.023 0.029 0.026 0.027 0.026 0.035 0.03 E 0.027 0.033 0.028 0.03 0.022 0.013 0.029 0.028 0.032 0.022 0.032 0.03 F 0.028 0.024 0.026 0.028 0.027 0.028 0.022 0.028 0.017 0.014 0.021 0.027 G 0.028 0.032 0.024 0.026 0.037 0.021 0.029 0.017 0.018 0.016 0.024 0.034 H 0.032 0.019 0.025 0.023 0.025 0.014 0.028 0.014 0.018 0.013 0.022 0.025 Graph 1 A1-4 A5-8 A9-12 B1-4 B5-8 B9-12 Mean 0.819 2.362 2.558 0.492 2.078 0.878 Standard Dev. 0.105 0.115 0.183 0.100 0.258 0.133 Graph 2 A1-4 A5-8 A9-12 B1-4 B5-8 B9-12 Mean 0.201 0.370 0.346 0.158 0.325 0.407 Standard Dev. 0.009 0.023 0.067 0.020 0.031 0.021 Discussion ECM Component Preference As was previously discussed, cadhesins are of various different types and thus may have different preferences for the extra-cellular matrix in which they react. In the data above, the cells A1-4 represent matrix 1, A5-8 represent matrix 2, and A9-12 represent matrix 3. The cells B1-4 represent the BSA and B5-8 and B9-12 represent tube 1 and 2 respectively. In this case, the data obtained experimentally shows that there is a definite component preference for matrices 2 and 3, with the first one having a very low absorbance value and thus a very low amount of adhering cells. The sample data also show a similar trend, although the amount of adhering cells in matrix 1 are not so low as in the experimental data. There is another small difference in