PMC

Current RABIT protocols for the micronucleus assay (left) and the γ-H2AX assay (right).

a) Schematic of RABIT layout; b) breadboard prototype; c) prototype transfer-to- substrate system; d) prototype imaging system.

RABIT image analysis. Top: γ-H2AX analysis: a) imaged nuclei; b) imaged γ-H2AX fluorescence; c) γ-H2AX fluorescence integrated within the boundaries of each nucleus (green line). Bottom: Micronuclei analysis: d) imaged nuclei; e) imaged cytoplasm; f) nucleus and cytoplasm images are binarized, subtracted, and “holes” scored.

Irradiated lymphocytes on RABIT filter membranes: A) the γ-H2AX assay: here the large blue blob corresponds to the nucleus, and the orange foci correspond to DNA double-strand breaks; the total amount of orange fluorescence is the measured quantity. B) The micronucleus assay: here the orange blob is the cytoplasm, the two large blue blobs are divided binucleates, and the small blue blob is a micronucleus.

a) A barcoded capillary from the RABIT system. b) A 32 capillary holder from the RABIT, loaded with blood-filled capillaries in Arizona and then shipped to New York. As seen in three capillaries shown outside the holder, a good layering of blood and separation medium was seen after this transport exercise. c) A capillary after automated centrifuging, showing good separation between the lymphocyte band and the red blood cells.