Immunoglobulin G against myelin oligodendrocyte glycoprotein(MOG-Ig G) is detectable in neuromyelitis optica spectrum disorder(NMOSD) without aquaporin-4 Ig G(AQP4-Ig G), but its pathogenicity remains unclear.In this ...Immunoglobulin G against myelin oligodendrocyte glycoprotein(MOG-Ig G) is detectable in neuromyelitis optica spectrum disorder(NMOSD) without aquaporin-4 Ig G(AQP4-Ig G), but its pathogenicity remains unclear.In this study, we explored the pathogenic mechanisms of MOG-Ig G in vitro and in vivo and compared them with those of AQP4-Ig G. MOG-Ig G-positive serum induced complement activation and cell death in human embryonic kidney(HEK)-293 T cells transfected with human MOG. In C57 BL/6 mice and Sprague-Dawley rats, MOG-Ig G only caused lesions in the presence of complement. Interestingly, AQP4-Ig G induced astroglial damage, while MOGIg G mainly caused myelin loss. MOG-Ig G also induced astrocyte damage in mouse brains in the presence ofcomplement. Importantly, we also observed ultrastructural changes induced by MOG-Ig G and AQP4-Ig G. These findings suggest that MOG-Ig G directly mediates cell death by activating complement in vitro and producing NMOSDlike lesions in vivo. AQP4-Ig G directly targets astrocytes,while MOG-Ig G mainly damages oligodendrocytes.展开更多
Accommodated organs can survive in the presence of anti-organ antibodies and complement. Heme oxygenase-1 （HO-1） is essential to ensure accommodation in concordant xenotransplant models. However, whether induction o...Accommodated organs can survive in the presence of anti-organ antibodies and complement. Heme oxygenase-1 （HO-1） is essential to ensure accommodation in concordant xenotransplant models. However, whether induction of HO-1 over-expression could protect porcine endothelial cells （PECs） against human xenoantibodies and complement-mediated lysis and induce an in vitro accommodation is still unknown. The SV40-immortalized porcine aorta-derived endothelial cell line （iPEC） was pre-incubated with 20, 50, or 80 μmol/L of cobalt-protoporphyrins IX （CoPPIX） for 24 h, and the HO-1 expression in iPECs was analyzed by using Western blotting. CoPPIX-treated or untreated iPECs were incubated with normal human AB sera, and complement-dependent cytotoxicity （CDC） was measured by both flow cytometry and lactate dehydrogenase （LDH） release assay. In vitro treatment with CoPPIX significantly increased the expression of HO-1 in iPECs in a dose-dependent manner. Over-expression of HO-1 was successfully achieved by incubation of iPECs with either 50 or 80 μmol/L of CoPPIX. However, HO-1 over-expression did not show any protective effects on iPECs against normal human sera-mediated cell lysis. In conclusion, induction of HO-1 over-expression alone is not enough to pro- tect PECs from human xenoantibodies and complement-mediated humoral injury. Additionally, use of other protective strategies is needed to achieve accommodation in pig-to-primate xenotransplantation.展开更多
Therapeutic monoclonal antibodies are among the most effective biotherapeutics to date. An important aspect of antibodies is their ability to bind antigen while at the same time recruit immune effector functions. The ...Therapeutic monoclonal antibodies are among the most effective biotherapeutics to date. An important aspect of antibodies is their ability to bind antigen while at the same time recruit immune effector functions. The majority of approved recombinant monoclonal antibody therapies are of the human IgG1 subclass, which can engage both humoral and cellular components of the immune system. The wealth of information generated about antibodies has afforded investigators the ability to molecularly engineer antibodies to modulate effector functions. Here, we review various antibody engineering efforts intended to improve efficacy and safety relative to the human IgG isotype. Further, we will discuss pro- posed mechanisms by which engineering approaches led to modified interactions with immune components and provide examples of clinical studies using next generation antibodies.展开更多
基金supported by grants from the National Natural Science Foundation of China (81471218 and 81771300)the Natural Science Foundation of Guangdong Province, China (2017A030313853)
文摘Immunoglobulin G against myelin oligodendrocyte glycoprotein(MOG-Ig G) is detectable in neuromyelitis optica spectrum disorder(NMOSD) without aquaporin-4 Ig G(AQP4-Ig G), but its pathogenicity remains unclear.In this study, we explored the pathogenic mechanisms of MOG-Ig G in vitro and in vivo and compared them with those of AQP4-Ig G. MOG-Ig G-positive serum induced complement activation and cell death in human embryonic kidney(HEK)-293 T cells transfected with human MOG. In C57 BL/6 mice and Sprague-Dawley rats, MOG-Ig G only caused lesions in the presence of complement. Interestingly, AQP4-Ig G induced astroglial damage, while MOGIg G mainly caused myelin loss. MOG-Ig G also induced astrocyte damage in mouse brains in the presence ofcomplement. Importantly, we also observed ultrastructural changes induced by MOG-Ig G and AQP4-Ig G. These findings suggest that MOG-Ig G directly mediates cell death by activating complement in vitro and producing NMOSDlike lesions in vivo. AQP4-Ig G directly targets astrocytes,while MOG-Ig G mainly damages oligodendrocytes.
基金supported by the Program for New Century Excellent Talents in University (No. NCET-06-0637)
文摘Accommodated organs can survive in the presence of anti-organ antibodies and complement. Heme oxygenase-1 （HO-1） is essential to ensure accommodation in concordant xenotransplant models. However, whether induction of HO-1 over-expression could protect porcine endothelial cells （PECs） against human xenoantibodies and complement-mediated lysis and induce an in vitro accommodation is still unknown. The SV40-immortalized porcine aorta-derived endothelial cell line （iPEC） was pre-incubated with 20, 50, or 80 μmol/L of cobalt-protoporphyrins IX （CoPPIX） for 24 h, and the HO-1 expression in iPECs was analyzed by using Western blotting. CoPPIX-treated or untreated iPECs were incubated with normal human AB sera, and complement-dependent cytotoxicity （CDC） was measured by both flow cytometry and lactate dehydrogenase （LDH） release assay. In vitro treatment with CoPPIX significantly increased the expression of HO-1 in iPECs in a dose-dependent manner. Over-expression of HO-1 was successfully achieved by incubation of iPECs with either 50 or 80 μmol/L of CoPPIX. However, HO-1 over-expression did not show any protective effects on iPECs against normal human sera-mediated cell lysis. In conclusion, induction of HO-1 over-expression alone is not enough to pro- tect PECs from human xenoantibodies and complement-mediated humoral injury. Additionally, use of other protective strategies is needed to achieve accommodation in pig-to-primate xenotransplantation.
文摘Therapeutic monoclonal antibodies are among the most effective biotherapeutics to date. An important aspect of antibodies is their ability to bind antigen while at the same time recruit immune effector functions. The majority of approved recombinant monoclonal antibody therapies are of the human IgG1 subclass, which can engage both humoral and cellular components of the immune system. The wealth of information generated about antibodies has afforded investigators the ability to molecularly engineer antibodies to modulate effector functions. Here, we review various antibody engineering efforts intended to improve efficacy and safety relative to the human IgG isotype. Further, we will discuss pro- posed mechanisms by which engineering approaches led to modified interactions with immune components and provide examples of clinical studies using next generation antibodies.
