Expression of metalloproteinase-2 (gelatinase A) in labial salivary glands of patients with Sj?gren's syndrome with HTLV-I infection.

OBJECTIVE: To determine whether gelatinase A (MMP-2) plays a significant role in the pathogenesis of Sj?gren's syndrome (SS) with or without HTLV-I infection. METHODS: We examined 24 patients with SS (14 HTLV-I-seropositive and 8 HTLV-I-seronegative). Labial salivary gland tissue samples were analysed immunohistochemically using anti-MMP-2 monoclonal antibodies. RESULTS: In normal salivary glands, MMP-2 expression was not detected. All biopsy samples of 8 SS patients with HTLV-I-associated myelopathy (HAM) and 3 of 6 HTLV-I-seropositive SS patients without manifestation of HAM stained positively for MMP-2. However, the other samples were negative for MMP-2. CONCLUSION: Our study showed the MMP-2 expression in labial salivary glands of HTLV-I seropositive SS patients, especially in all SS patients with HAM. The presence of MMP-2 in the salivary glands of these patients suggests that it may play a role in cellular infiltration and destruction in salivary glands of SS.