Objective: To evaluate monkey liver tissue and human epithelial cells (Hep-2) as substrates for detection of antinuclear antibodies(ANA) in clinical use. Methods: Monkey liver tissue and Hep-2 cells were compared as substrates for detection of ANA in the serum of 118 patients with different connective tissue disease (CTD)

80 patients with no CTD and 50 normal subjects

using indirect immunofluorescence assay. Results: ANA on Hep-2 cells produced more positive results than ANA on monkey liver tissue

and the difference between them was statistically significant(P<0.05). Compared with the groups of non-CTD and normal

the positive rate of ANA on monkey liver tissue and Hep-2 cell in the groups of CTD was significantly different (P<0.001)

and there was no significant difference between the groups of non-CTD and normal (P>0.05). The observation of ANA titer is helpful for diagnosis of CTD. Conclusion: ANA should be detected by Monkey liver tissue and Hep-2 cells.