DIFFERENTIATION OF LEISHMANIA PROMASTIGOTES

利什曼原虫前鞭毛体的分化

• 批准号: 3818156
• 负责人: D L SACKS
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3818156
• 关键词: India; Leishmania; antimicroorganism antibody; complement pathway; complement receptor; glycolipids; host organism interaction; immune tolerance /unresponsiveness; immunotherapy; interleukin 2; intracellular parasitism; laboratory mouse; lectin; leishmaniasis; macrophage; microorganism culture; microorganism growth; monoclonal antibody; protozoal antigen; sialate; suppressor T lymphocyte; virulence

The differentiation of L. major promastigotes from a non-infective to an infective or metacyclic stage is accomplished by changes in surface carbohydrates which can be detected by the lectin peanut agglutinin (PNA). On non-infective, logarithmic phase promastigotes, PNA binds to the surface lipophosphoglycan (LPG). During metacyclogenesis, the LPG is developmentally modified such that it no longer binds PNA, it expresses a novel carbohydrate epitope, and it is substantially increased in size. A major difference between the two forms can be localized to the composition of the tetrasaccharide subunits of the phosphorylated carbohydrates. The manner in which this structural change promotes complement resistance and intracellular survival is being investigated. The major acceptor molecular for C3b deposition on metacyclics is the LPG, which remain resistant to lysis because the membrane attack complex, while formed, is released from the surface. Efficient deposition of C3b in the absence of lysis promotes uptake of opsonized promastigotes by macrophage CR1 receptors.

大promastigotes与非感染性L.的分化