[Application of a human immortalized fibroblast cell line in laboratory diagnosis of autoimmune diseases]

Many autoantibodies reacting with cellular and nuclear components have been described in sera of patients with autoimmune diseases. The most important diagnostic markers for those diseases are antinuclear antibodies (ANA). The first choice for laboratory diagnosis of autoimmune diseases is to use cultured monolayer cells as a nuclear substrate. Up to now the HEp-2 cell line derived from a human carcinoma of the larynx, appears to be the most sensitive and specific nuclear substrate. The cultured fibroblast monolayer cells have also been applied to detect the ANA, although the application was not recommended by one study. Thus to evaluate the applicability of our immortalized human fibroblast cell line (CCFS-1/KMC) as a nuclear substrate, commercial HEp-2 MBL monolayer cells was used as the standard substrate. The results of this report showed the applicability of the CCFS-1/KMC cell line as a nuclear substrate to detect the ANA of autoimmune diseases. The sensitivity of this fibroblast cell line was the same as both of the HEp-2 nuclear substrates (HEp-2 and HEp-2 MBL). The specificity of the CCFS-1/KMC cell line was similar to the HEp-2 substrate. Since the specificity of both of the above substrates were lower than the standard nuclear substrate HEp-2 MBL, therefore, if the specificity can be improved by changing the protocols of the substrate preparation, the CCFS-1/KMC cell line will be a good nuclear substrate for detecting the ANA of autoimmune diseases.