- Th1/Th2 cytokine imbalance in patients with Sjögren syndrome secondary to hepatitis C virus infection. Ramos-Casals, M., García-Carrasco, M., Cervera, R., Filella, X., Trejo, O., de la Red, G., Gil, V., Sánchez-Tapias, J.M., Font, J., Ingelmo, M. Semin. Arthritis Rheum. (2002)