Difference between revisions of "Part:BBa K2632008"

Revision as of 12:17, 13 October 2018

Plac-Lpp-OmpA-RGD

We gave the surface display systerm from BBa_J36850 a new fuction though displaying RGD motif on the Lpp-OmpA in E. coli. RGD motif can specifically bind to αVβ3 a biomarker of cancer cells¹. In addition, A rescent study successfully used Salmonella display RGD motif to target αVβ3-positive tumor cells2. We determine surface display site on the third loop of ompA though homology modelling (Figure 1). This part is under the control of Lac promoter.
Figure 1. Homology modelling result of Lpp-OmpA-RGD. Red arrow shows the location of RGD motif.
Microscopy shows that E. coli expressed Lpp-OmpA-RGD induced by 0.1mM IPTG can bind to αVβ3-positive MDA-MB-231 cell line. Red arrow point location of bacteria (Figure 2). But can not bind to αVβ3-negative MCF7 cell line (Figure 3). We also use BBa_J36850 as a control. This strain can not bind to Vβ3-positive MDA-MB-231 cell line (Figure 4) and αVβ3-negative MCF7 cell line (Figure 5). These results suggest that we successfully improve the part BBa_J36850. (Click here to see method)
Figure 2. αVβ3-positive MDA-MB-231 cell line was incubated with E.coli which constructive expressed RFP and contained contained BBa_J36850. This improved part expresses RGD motif under control of Plac. Figure 3. αVβ3-negative MCF7 cell line was incubated with E.coli which constructive expressed RFP and contained contained BBa_J36850. This improved part expresses RGD motif under control of Plac. Figure 4. αVβ3-positive MDA-MB-231 cell line was incubated with E.coli which constructive expressed RFP and contained BBa_J36850. Figure 5. αVβ3-negative MCF7 cell line was incubated with E.coli which constructive expressed RFP and contained BBa_J36850.

Reference

Park, S. H. et al. RGD peptide cell-surface display enhances the targeting and therapeutic efficacy of attenuated salmonella-mediated cancer therapy. Theranostics 6, 1672–1682 (2016).