文章基本信息

标题：Immunological memory to blood-stage malaria infection is controlled by the histamine releasing factor (HRF) of the parasite
本地全文：下载
作者：Claudia Demarta-Gatsi ; Roger Peronet ; Leanna Smith 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2017
卷号：7
期号：1
DOI：10.1038/s41598-017-09684-2
语种：English
出版社：Springer Nature
摘要：While most subunit malaria vaccines provide only limited efficacy, pre-erythrocytic and erythrocytic genetically attenuated parasites (GAP) have been shown to confer complete sterilizing immunity. We recently generated a Plasmodium berghei (PbNK65) parasite that lacks a secreted factor, the histamine releasing factor (HRF) (PbNK65 hrfΔ), and induces in infected mice a self-resolving blood stage infection accompanied by a long lasting immunity. Here, we explore the immunological mechanisms underlying the anti-parasite protective properties of the mutant PbNK65 hrfΔ and demonstrate that in addition to an up-regulation of IL-6 production, CD4(+) but not CD8(+) T effector lymphocytes are indispensable for the clearance of malaria infection. Maintenance of T cell-associated protection is associated with the reduction in CD4(+)PD-1(+) and CD8(+)PD-1(+) T cell numbers. A higher number of central and effector memory B cells in mutant-infected mice also plays a pivotal role in protection. Importantly, we also demonstrate that prior infection with WT parasites followed by a drug cure does not prevent the induction of PbNK65 hrfΔ-induced protection, suggesting that such protection in humans may be efficient even in individuals that have been infected and who repeatedly received antimalarial drugs.