Detection of anti-nuclear autoantibodies in sera of C57BL/6.NOD-Aec1RAec2R(n) mice. Serum samples obtained from C57BL/6.NOD-Aec1Aec2R(n) mice were diluted 1:40 and incubated with HEp-2 fixed substrate slides for 30 minutes at 25°C in a humidified chamber. The slides were then developed with Alexa 594-conjugated goat anti-mouse IgG and viewed by fluorescence microscopy at × 100 magnification. Examples of speckled/homogenous staining of the nucleus (left panel), cytoplasmic/nuclear membrane staining (left center panel), speckled/cytoplasmic staining (right center panel), and cytoplasmic staining (right panel) were observed. The numbers of individual sera tested and the percentages of positive sera from a sampling of recombinant inbred (RI) lines exhibiting each of the patterns are listed. §Number of mice showing positive staining pattern over total. *Percentage of mice showing positive staining pattern. Aec, autoimmune exocrinopathy.