Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.
Albert Einstein College of Medicine, Bronx, New York, USA.
JCI Insight. 2020 Jun 18;5(12):136279. doi: 10.1172/jci.insight.136279.
BACKGROUNDPrediction of adverse outcomes in cerebral malaria (CM) is difficult. We hypothesized that cell-free DNA (cfDNA) levels would facilitate identification of severe and potentially fatal CM cases.METHODSIn this retrospective study, plasma from Malawian children with CM (n = 134), uncomplicated malaria (UM, n = 77), and healthy controls (HC, n = 60) was assayed for cfDNA using a fluorescence assay. Host and parasite cfDNA was measured by quantitative PCR. Immune markers were determined by ELISA, Luminex, or cytometric bead array.RESULTSTotal cfDNA increased with malaria severity (HC versus UM, P < 0.001; HC versus CM, P < 0.0001; UM versus CM, P < 0.0001), was elevated in retinopathy-positive (Ret+) CM relative to Ret- CM (7.66 versus 5.47 ng/μL, P = 0.027), and differentiated Ret+ fatal cases from survivors (AUC 0.779; P < 0.001). cfDNA levels in patients with non-malarial febrile illness (NMF, P = 0.25) and non-malarial coma (NMC, P = 0.99) were comparable with UM. Host DNA, rather than parasite DNA, was the major cfDNA contributor (UM, 268 versus 67 pg/μL; CM, 2824 versus 463 pg/μL). Host and parasite cfDNA distinguished CM by retinopathy (host, AUC 0.715, P = 0.0001; parasite, AUC 0.745, P = 0.0001), but only host cfDNA distinguished fatal cases (AUC 0.715, P = 0.0001). Total cfDNA correlated with neutrophil markers IL-8 (rs = 0.433, P < 0.0001) and myeloperoxidase (rs = 0.683, P < 0.0001).CONCLUSIONQuantifying plasma cfDNA is a simple assay useful in identifying children at risk for fatal outcome and has promise as a point-of-care assay. Elevated cfDNA suggests a link with host inflammatory pathways in fatal CM.FUNDINGNIH NCATS (AK), Burroughs-Wellcome (AK), and National Health and Medical Research Council of Australia (SJR).
预测脑型疟疾（CM）的不良结局较为困难。我们假设，无细胞 DNA（cfDNA）水平有助于识别严重和潜在致命的 CM 病例。
在这项回顾性研究中，我们使用荧光测定法检测了来自马拉维患有 CM（n=134）、无并发症疟疾（UM，n=77）和健康对照（HC，n=60）的儿童的血浆中的 cfDNA。通过定量 PCR 测量宿主和寄生虫 cfDNA。通过 ELISA、Luminex 或流式细胞术测定免疫标志物。
总 cfDNA 随着疟疾严重程度的增加而升高（HC 与 UM，P<0.001；HC 与 CM，P<0.0001；UM 与 CM，P<0.0001），在视网膜病变阳性（Ret+）CM 中高于 Ret- CM（7.66 与 5.47ng/μL，P=0.027），并区分了 Ret+致命病例和幸存者（AUC 0.779；P<0.001）。非疟疾性发热性疾病（NMF，P=0.25）和非疟疾性昏迷（NMC，P=0.99）患者的 cfDNA 水平与 UM 相似。宿主 DNA 而非寄生虫 DNA 是主要的 cfDNA 贡献者（UM，268 与 67pg/μL；CM，2824 与 463pg/μL）。宿主和寄生虫 cfDNA 通过视网膜病变区分 CM（宿主，AUC 0.715，P=0.0001；寄生虫，AUC 0.745，P=0.0001），但只有宿主 cfDNA 区分致命病例（AUC 0.715，P=0.0001）。总 cfDNA 与中性粒细胞标志物白细胞介素 8（rs=0.433，P<0.0001）和髓过氧化物酶（rs=0.683，P<0.0001）相关。
定量检测血浆 cfDNA 是一种简单的检测方法，有助于识别有致命结局风险的儿童，并且有望成为一种即时检测方法。cfDNA 升高提示与致命性 CM 中的宿主炎症途径有关。
NIH NCATS（AK）、Burroughs-Wellcome（AK）和澳大利亚国家卫生与医学研究理事会（SJR）。
