We analyse the spatially resolved relation between stellar mass (M$_{star}$) and star formation rate (SFR) in disk galaxies (i.e. the Main Sequence, MS). The studied sample includes eight nearby face-on grand-design spirals, e.g. the descendant of high-redshift, rotationally-supported star-forming galaxies. We exploit photometric information over 23 bands, from the UV to the far-IR, from the publicly available DustPedia database to build spatially resolved maps of stellar mass and star formation rates on sub-galactic scales of 0.5-1.5 kpc, by performing a spectral energy distribution fitting procedure that accounts for both the observed and the obscured star formation processes, over a wide range of internal galaxy environments (bulges, spiral arms, outskirts). With more than 30 thousands physical cells, we have derived a definition of the local spatially resolved MS per unit area for disks, $log(Sigma_{SFR})$=0.82log$(Sigma_{*})$-8.69. This is consistent with the bulk of recent results based on optical IFU, using the H$alpha$ line emission as a SFR tracer. Our work extends the analysis at lower sensitivities in both M$_{star}$ and SFR surface densities, up to a factor $sim$ 10. The self consistency of the MS relation over different spatial scales, from sub-galactic to galactic, as well as with a rescaled correlation obtained for high redshift galaxies, clearly proves its universality.
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