Team:TU Eindhoven/Project/Characterization/Antifouling Properties

Antifouling Assay

One of the applications for the click coli system was to evade the immune system. This was attempted by clicking large PEG tails to the bacteria. The PEG tails create a hydrophilic environment, blocking possible interactions between the bacteria and anti-bodies.

First PEG 10kDa was clicked to the membrane of the bacteria. The bacteria were then incubated in a solution with fluorescently labelled Anti-HA anti-bodies (316 nM), COMPx (membrane protein) contains a HA-tag which is targeted by the antibodies, and after incubation the bacteria were washed. There were two types of control groups used, positive and negative. For negative control one with only bacteria and another one with bacteria and DBCO. For the positive control bacteria with anti-HA antibody and no DBCO were used.

Results show that there is a decrease in fluorescence of the bacteria that have a PEG 10kDa. This means that there are less Anti-HA antibodies bound to the HA-tag on the membrane of the bacteria coated with PEG 10kDA. The number of antibodies bound to these bacteria is still too high to say it evades an immune response. This was not unexpected because PEG tails do not form a network; they just stick out of the membrane. To get a further decrease in antibodies bound usage of a polymer that can also crosslink to form a network is a good possibility. Possible future improvements are discussed in Future Perspectives