Hiv相关的血小板由过氧化物诱导的抗体所致
&nbps;&nbps;&nbps;&nbps;WESTPORT, CT (Reuters Health) - The suspected antibody involved in immune thrombocytopenia that commonly occurs with HIV infection, has a novel ability to lyse platelets in a complement-independent manner by inducing peroxide, according to findings published in the September 7th issue of Cell.
&nbps;&nbps;&nbps;&nbps;"This was an unexpected finding because antibodies had never been shown to act in this fashion," study director, Dr. Simon Karpatkin, says in a statement from New York University School of Medicine. "It is conceivable that this antibody could be used to dissolve clots in the arteries," he adds, a possibility that has implications for a wide range of cardiovascular diseases.
&nbps;&nbps;&nbps;&nbps;Dr. Karpatkin and others at NYU examined the mechanisms underlying the development of HIV-1-related immune thrombocytopenia in mice. They injected the mice with anti-platelet membrane GPIIIa49-66 IgG antibodies, a component of the immune complexes associated with immune thrombocytopenia in HIV-infected humans.
&nbps;&nbps;&nbps;&nbps;The antibodies caused platelet lysis in wild-type mice, as well as complement (C3)-deficient mice. Platelet lysis was initiated by antibody stimulation of an NADPH oxidase pathway, and was inhibited by peroxide inhibitors and other inhibitors of reactive oxygen species. In addition, the anti-platelet antibodies did not stimulate platelet lysis in NADPH-deficient mice.
&nbps;&nbps;&nbps;&nbps;"These data reveal a new pathophysiologic mechanism for platelet destruction (fragmentation) by an autoantibody specific for a platelet GPIIIa49-66 epitope," the investigators say in Cell. The findings highlight potential new avenues for treating a variety of platelet-associated disorders, including myocardial infarction and stroke., 百拇医药
&nbps;&nbps;&nbps;&nbps;"This was an unexpected finding because antibodies had never been shown to act in this fashion," study director, Dr. Simon Karpatkin, says in a statement from New York University School of Medicine. "It is conceivable that this antibody could be used to dissolve clots in the arteries," he adds, a possibility that has implications for a wide range of cardiovascular diseases.
&nbps;&nbps;&nbps;&nbps;Dr. Karpatkin and others at NYU examined the mechanisms underlying the development of HIV-1-related immune thrombocytopenia in mice. They injected the mice with anti-platelet membrane GPIIIa49-66 IgG antibodies, a component of the immune complexes associated with immune thrombocytopenia in HIV-infected humans.
&nbps;&nbps;&nbps;&nbps;The antibodies caused platelet lysis in wild-type mice, as well as complement (C3)-deficient mice. Platelet lysis was initiated by antibody stimulation of an NADPH oxidase pathway, and was inhibited by peroxide inhibitors and other inhibitors of reactive oxygen species. In addition, the anti-platelet antibodies did not stimulate platelet lysis in NADPH-deficient mice.
&nbps;&nbps;&nbps;&nbps;"These data reveal a new pathophysiologic mechanism for platelet destruction (fragmentation) by an autoantibody specific for a platelet GPIIIa49-66 epitope," the investigators say in Cell. The findings highlight potential new avenues for treating a variety of platelet-associated disorders, including myocardial infarction and stroke., 百拇医药