Fig. 5

Comparison of the optimized protocol to the basic protocol. Cancer cell-spiked bone marrow was stained with (stained) and without (unstained) primary antibody using the basic or optimized protocol. Image exposure time was increased for primary unstained slides compared to stained slides, but was consistent between basic and optimized protocols for each. Filled white arrowheads point to true positive staining. Open solid arrowheads indicate false staining due to non-specific binding of secondary antibody. Scale bar = 50 μm