Fig 6. Autofluorescence and specific fluorescence threshold for quantification.

Intensity images of FFPE kidney sections, unstained (autofluorescence) or stained with for CD68 using specific Ab and secondary conjugated with Qdot were quantified at the peak of fluorescence using Nuance software. This was performed for each Qdot, illuminated by each light source. The figure shows the example of the emission at 605nm for a slide labelled with Qdot 605 and an unstained section from the same tissue (autofluorescence) illuminated by LED4000 435nm. A: Intensity image of kidney tubules autofluorescence at 605nm, and corresponding thresholded areas for quantification of the autofluorescence intensity. B: Intensity image of a serial section labelled with Qdot 605 at 605nm and thresholded image for quantification (minimum 100 pixels connected).