High-dose intravenous immunoglobulin therapy for rapidly progressive interstitial pneumonitis accompanied by anti-melanoma differentiation-associated gene 5 antibody-positive amyopathic dermatomyositis.

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive amyopathic dermatomyositis (ADM) associated with rapidly progressive interstitial pneumonitis (RPIP) frequently has a poor prognosis and optimal treatment is not well defined. Here, we report a 62-year-old Japanese man with anti-MDA5 antibody-positive ADM associated with RPIP presented with progressive shortness of breath, Heliotrope rash, Gottron's papules, arthralgia, and fatigue but no sign of muscle weakness. Laboratory investigation revealed serum levels of the following biomarkers: ferritin, 1393 ng/mL; Krebs von der Lungen-6, 1880 U/mL; and creatine kinase, 85 U/L. Computed tomography (CT) images showed diffuse ground-glass opacity in both lung fields. Because anti-MDA5 was positive, we made a diagnosis of ADM associated with RPIP and initiated treatment. Following five courses of combination therapy with prednisolone, cyclosporine A, and intravenous cyclophosphamide (IVCY), IVCY treatment was switched to high-dose intravenous immunoglobulin therapy (IVIg) because of the reactivation of interstitial pneumonia with an increased serum ferritin level. Additional treatment with IVIg improved RPIP, with normalization of anti-ADM antibody levels. Therefore, IVIg mayt be a new candidate treatment for anti-MDA5 antibody-positive ADM associated with RPIP.

A silkworm baculovirus model for assessing the therapeutic effects of antiviral compounds: characterization and application to the isolation of antivirals from traditional medicines.

Ganciclovir, foscarnet, vidarabine and ribavirin, which are used to treat viral infections in humans, inhibited the proliferation of a baculovirus (Bombyx mori nucleopolyhedrovirus) in BmN4 cells, a cultured silkworm cell line. These antiviral agents inhibited the proliferation of baculovirus in silkworm body fluid and had therapeutic effects. Using the silkworm infection model, the antiviral activity of Kampo medicines was screened and it was found that cinnamon bark, a component of the traditional Japanese medicine Mao-to, had a therapeutic effect. Based on the therapeutic activity, the antiviral substance was purified. Nuclear magnetic resonance analysis of the purified fraction revealed that the antiviral activity was due to cinnzeylanine, which has previously been isolated from Cinnamomum zeylanicum. Cinnzeylanine inhibits the proliferation of herpes simplex virus type 1 in Vero cells. These results suggest that the silkworm-baculovirus infection model is useful for screening antiviral agents that are effective for treating humans infected with DNA viruses.