Antinuclear antibodies in rabbit antisera.

Antinuclear antibodies were detected by immunofluorescence in most sera from rabbits immunized with whole human serum emulsified in Freund's complete adjuvant. Four of 14 sera from rabbits immunized with Cohn fractions III, IV-1, or IV-4 also gave positive nuclear fluorescence with human leukocyte nuclei. Other human and animal nuclei gave negative results with these rabbit antisera. Three rabbit anti-whole human sera had complement-fixing antibody against DNA in sufficient titer for study in quantitative complement fixation tests. Antibody with greatest reactivity with human single strand DNA was detected in the 3 rabbit antisera. Reactivity with rabbit, calf thymus, and B. natto DNA was also detected. In each case reactivity was greater with single strand than with native DNA. Antibodies against human histone and purine-6-oly BSA were also detected. No correlation was found between the titers of rheumatoidlike factors and antinuclear antibodies present in the rabbit antisera. The induction of antinuclear antibodies in these rabbits was not associated with disease attributable to the antibodies. The induction of antinuclear antibody by immunization with whole human serum was interpreted as indicating the presence of antigenic nuclear material in whole human serum.