Developments in digital imaging and fluorescent microscopy provide a new method and opportunities for quantification of protein expression in human tissue. Archived collections of paraffin-embedded tumors can be used to study the relationship between quantitative differences in protein expression in tumors and patient outcome. In this report we describe the use of a DeltaVision Restoration deconvolution microscope, combined with fluorescent immunohistochemistry, to obtain reproducible and quantitative estimates of protein expression in a formalin-fixed paraffin-embedded tissue. As proof of principle, we used antibodies to the estrogen and progesterone receptors in a hormone receptor-positive breast cancer specimen. We provide guidelines for control of day-to-day variability in camera and microscope performance to ensure that image acquisition leads to reproducible quantitative estimates of protein expression. We show that background autofluorescence related to formalin fixation can be controlled and that for proteins that are expressed in nearly every cell, multiplexing two primary antibodies on the same slide does not significantly affect the results obtained. We demonstrate that for proteins whose expression varies markedly from cell to cell, data reproducibility, as assessed by imaging successive tissue sections, is more difficult to determine.

Much research on color representation and categorization has assumed that relations among color terms can be proxies for relations among color percepts. We test this assumption by comparing the mapping of color words with color appearances among different observer groups performing cognitive tasks: (1) an invariance of naming task; and (2) triad similarity judgments of color term and color appearance stimuli within and across color categories. Observer subgroups were defined by perceptual phenotype and photopigment opsin genotype analyses. Results suggest that individuals rely on at least two different representational models of color experience: one lexical, conforming to the culture's normative linguistic representation, and another individual perceptual representation organizing each observer's color sensation experiences. Additional observer subgroup analyses suggest that perceptual phenotype variation within a language group may play a greater role in the shared color naming system than previously thought. A reexamination of color naming data in view of these findings may reveal influences on color naming important to current theories.