[Analysis of magnetic resonance imaging characteristics in Chinese patients with myelin oligodendrocyte glycoprotein antibody associated disorders]

Objective: To investigate the magnetic resonance imaging (MRI) characteristics in the brain and spinal cord of Chinese patients with myelin oligodendrocyte glycoprotein antibodies associated diseases (MOGAD). Methods: Forty nine MOGAD patients with seropositive MOG-IgG and 58 AQP4-IgG positive patients were enrolled in this study. The characteristics of brain and spinal cord MRI were retrospectively analyzed. Results: There was no significant difference in the proportion of abnormal brain MRI of the two groups (69.4% vs 65.5%, P=0.177) , while the proportion of abnormal spinal cord MRI of the AQP4-IgG positive group was significantly higher than that in the MOG-IgG positive group (84.5% vs 36.7%, P=0.001) . The proportion of MOG-IgG positive patients with subcortical white matter lesions and large lesions in the brain MRI was significantly higher than that in AQP4-IgG positive group (48.9% vs 13.8%, P=0.003, 46.9% vs 12.1%, P=0.000) . The longitudinally extensive transverse myelitis in spinal cord MRI of AQP4-IgG positive group was significantly higher than that in the MOG-IgG group (70.7% vs 24.5%, P=0.002) . In addition, the proportion of MOG-IgG positive child patients with large lesions in the brain was significantly higher than that in AQP4-IgG positive child patients (76.9% vs 20.0%, P=0.047) . Conclusion: Demyelinating MRI lesions caused by MOG-IgG are heterogeneous, and could lead to a wide range of clinical phenotypes which is significantly different from those with AQP4-IgG.

Scleromyxedema secondary to hepatitis C virus and successfully treated with antiviral therapy

Scleromyxedema (SM) is a chronic and progressive fibromucinous disease with no known etiology. We report a patient with scleromyxedema associated with hepatitis C virus, successfully treated with interferon and ribavirin therapy.

Mechanism of antitumor activity of a single-chain interleukin-12 IgG3 antibody fusion protein (mscIL-12.her2.IgG3)

We have constructed an antibody interleukin-12 (IL-12) fusion protein (mscIL-12.her2.IgG3) that demonstrates significant antitumor activity against the murine carcinoma CT26-expressing human HER2/neu. We now report that this antitumor activity is dose dependent and comparable to or better than recombinant murine IL-12 (rMuIL-12) using subcutaneous and metastatic models of disease. The antitumor activity of mscIL-12.her2.IgG3 is reduced in Rag2 knockout mice, suggesting that T cells play a role in tumor rejection. In SCID-beige mice, the antitumor activity is further reduced, suggesting that natural killer (NK) cells or macrophages or both are also important. The isotype of the antibody response to HER2/neu is consistent with a switch from a Th2 to a Th1 immune response and the infiltration of mononuclear cell in tumors from mice treated with mscIL-12.her2.IgG3. Immunohistochemistry reveals that mscIL-12.her2.IgG3 is antiangiogenic. Thus, the mechanism of the antitumor activity exhibited by mscIL-12.her2.IgG3 is highly complex and involves a combination of T and NK cell activity, a switch to a Th1 immune response, and antiantiogenic activity. This is the first study comparing the in vivo antitumor activity of an antibody-IL-12 fusion protein and free IL-12. Our results suggest that antibody-IL-12 fusion proteins may be useful for the treatment of human cancer.

A single-chain IL-12 IgG3 antibody fusion protein retains antibody specificity and IL-12 bioactivity and demonstrates antitumor activity

IL-12 is a heterodimeric cytokine with many actions on innate and cellular immunity that may have antitumor and antimetastatic effects. However, systemic administration of IL-12 can be toxic. Tumor-specific Abs provide a means to selectively target a metastatic/residual nodule and deliver therapeutic quantities of an immunostimulatory molecule like IL-12 with lower systemic levels and ideally, toxicity. We report the construction and characterization of an Ab fusion protein in which single-chain murine IL-12 is fused to an anti-Her2/neu Ab at the amino terminus (mscIL-12.her2.IgG3). The use of single-chain IL-12 in the fusion protein simplifies vector construction, ensures equimolar concentrations of the two IL-12 subunits, and may confer greater stability to the fusion protein. SDS-PAGE analysis shows this 320-kDa protein is secreted and correctly assembled. FACS analysis demonstrates that this fusion protein binds to cells transfected with the Her2/neu Ag, thus retaining Ab specificity; this fusion protein also binds to a cell line and to PHA-activated PBMC that express the IL-12R, thus demonstrating cytokine receptor specificity. T cell proliferation assays and NK cytotoxicity assays demonstrate that this fusion protein exhibits IL-12 bioactivity comparable to recombinant murine IL-12. In vivo studies demonstrate that this fusion protein has antitumor activity. These results are significant and suggest that this IL-12 Ab fusion protein can effectively combine the therapeutic potential of IL-12 with the tumor-targeting ability of the Ab and may provide a viable alternative to systemic administration of IL-12.