Interferon activity and its characterization in the sera of patients with premalignant lesions arising in oral mucosa.

The interferon (IFN) assay of the sera from the 26 patients with premalignant lesions such as lichen planus and leukoplakia arising in oral mucosa was performed by the plaque-reduction assay with vesicular stomatitis virus in FL cells derived from human amniotic membrane. When the serum IFN activity was characterized by acid treatment, significant increase of acid-stable IFN in the patients was found as compared with those in the normal controls. The titers of gamma-like IFN defined by anti-HuIFN-alpha and anti-HuIFN-beta in the sera of patients of 50-79 years age group (n = 17, P less than 0.002) showed a highly significant increase as compared with the relevant normal controls (n = 20). All of the 26 patients were treated with topical administration of HuIFN-beta. When the correlation between prognosis of the disease and titers of serum IFN was investigated by measuring gamma-like IFN and acid-stable IFN in the sera of patients, all of 13 patients with good prognosis after the HuIFN-beta therapy showed significantly decreased levels of gamma-like IFN (P less than 0.01), whereas the serum level of acid-stable IFN after HuIFN-beta therapy showed a significant increase compared to that before the therapy (P less than 0.05). These findings indicate that the endogenous IFN system may be associated with the pathophysiology in patients with the oral mucosal lesions.