A Sample-to-Answer Point-of-Care Diagnostic for Recently Transfused Sickle Cell Anemia Patients in Low Resource Settings

针对资源匮乏地区最近输血的镰状细胞性贫血患者的从样本到答案的护理点诊断

• 批准号: 10564553
• 负责人: Rebecca R. Richards-Kortum
• 金额: $ 56.06万
• 依托单位: RICE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10564553
• 关键词: 5 year old; Abnormal Hemoglobins; Acute; Address; Affect; Africa; Africa South of the Sahara; Age; Alleles; Anemia; Biological Assay; Biomedical Engineering; Birth; Blood; Blood Transfusion; Blood capillaries; Blood donor; Blood specimen; Buffers; Cells; Cessation of life; Child; Child Care; Childhood; Clinical; Clinical Research; Code; Complex; Cytolysis; DNA; DNA amplification; DNA analysis; Detection; Devices; Diagnosis; Diagnostic; Diagnostic tests; Disease; Disease Management; Drops; Drug resistance; Early Diagnosis; Early treatment; Education; Electrophoresis; Emergency Situation; Equipment; Erythrocytes; Fingers; Freeze Drying; Genes; Genetic; Genomic DNA; Genotype; Globin; Goals; Hematological Disease; Hematology; Hemoglobin; Hemoglobin C Disease; High Pressure Liquid Chromatography; Hospitals; Human; Human Resources; Individual; Infant; Infrastructure; Inherited; Isoelectric Focusing; Lateral; Life; Malawi; Malignant Neoplasms; Medicine; Morbidity - disease rate; Mutation; Newborn Infant; Nucleic Acid Amplification Tests; Nucleic Acids; Nucleotides; Optics; Pain; Pathologic; Patients; Performance; Persons; Pilot Projects; Point Mutation; Point of Care Technology; Polymerase; Positioning Attribute; Preparation; Preventive treatment; Proteins; Provider; Reaction; Reagent; Research; Resource-limited setting; Rice; Sampling; Sensitivity and Specificity; Sickle Cell; Sickle Cell Anemia; Sickle Cell Trait; Sickle Hemoglobin; Specificity; Testing; Texas; Time; Training; Transfusion; Translating; Translational Research; Tube; Universities; Variant; Whole Blood; accurate diagnostics; acute care; beta Globin; clinical care; clinical diagnostics; clinically relevant; college; cost; design; diagnostic platform; diagnostic tool; disease diagnosis; disease diagnostic; experience; global health; hemoglobin polymer; improved; isothermal amplification; low and middle-income countries; meetings; mortality; neonate; novel; point of care; point of care testing; point-of-care diagnostics; prevent; rapid detection; recombinase; resistance mutation; screening; screening program; usability; user-friendly

Project Summary/Abstract Sickle cell disease (SCD) is an inherited hemoglobin disorder that is highly prevalent in low- and middle-income countries (LMICs), with over 75% of affected global births occurring in sub-Saharan Africa. Early diagnosis through pediatric screening, parental education, and preventive treatments are known to reduce deaths; however, lack of infrastructure and the high cost of diagnostic tools in low-resource settings severely limit early detection. As a result, many pediatric SCD patients present to a hospital with acute, severe anemia without a diagnosis and receive emergency blood transfusions. Existing point-of-care tests function by detecting and characterizing the hemoglobin proteins present in a sample. In cases of blood transfusion, these tests detect normal hemoglobin transfused from the blood donor as well as sickle hemoglobin, therefore misdiagnosing patients as sickle cell carriers. This limitation means existing point-of-care tests cannot be used for up to three months with patients who have received a blood transfusion, which causes significant delays in the time to diagnosis and prevents initiation of treatment. There is an urgent need for an inexpensive, easy-to-use test that targets the genetic basis of the disease and can rapidly deliver results so that accurate treatment can be initiated immediately at the point of care. To address this need, we will develop a rapid, inexpensive nucleic acid-based test to detect the common point mutations in the β globin gene that cause SCD: βS(Glu6Val) and βC(Glu6Lys). We propose a test that can differentiate the following clinically relevant genotypes: 1) SCD patients (βSβS: SS, βSβC: SC); 2) unaffected individuals (βAβA: AA); 3) SCD carriers (βAβS: AS, βAβC: AC); and 4) Hemoglobin C disease (βCβC: CC). Because blood transfusions contain globin proteins from the donor, a nucleic acid test is the only possibility to test infants and children who have recently undergone blood transfusions. An inexpensive point-of-care test that allows rapid detection of SCD in all patients would greatly improve care for children with SCD. We aim to: (1) Design and validate the first genetic point-of-care nucleic acid amplification test for sickle cell disease that can be used in recently transfused patients; (2) Implement the test on a low-cost, manufacturable, fully integrated sample-to-answer platform; and (3) Evaluate sensitivity, specificity, and usability of the test in two pilot clinical studies. Our team at Rice University, Baylor College of Medicine, and Kamuzu Central Hospital in Lilongwe, Malawi has the necessary expertise in bioengineering and clinical diagnostics to address the challenge of diagnosing SCD in resource-limited settings. Our proposed assay meets the optimal requirements for point-of-care testing in LMICs. Finally, it would eliminate the long delays currently associated with sample transport or transfusion from screen-positive patients to testing centers, and would enable immediate initiation of treatment for infants and children with a diagnosis of SCD.

项目总结/摘要 镰状细胞病（SCD）是一种遗传性血红蛋白疾病，在中低收入人群中非常普遍。 全球受影响的新生儿中有75%以上发生在撒哈拉以南非洲。早期诊断 通过儿科筛查、父母教育和预防性治疗，已知可减少死亡; 然而，在资源匮乏的环境中，基础设施的缺乏和诊断工具的高成本严重限制了早期诊断， 侦测因此，许多儿童SCD患者因急性严重贫血而入院， 诊断和接受紧急输血。现有的护理点测试通过检测和 表征样品中存在的血红蛋白。在输血的情况下，这些测试检测 献血者输入的正常血红蛋白和镰状血红蛋白，因此误诊 镰状细胞携带者。这一限制意味着现有的床旁检测最多不能用于三个 接受输血的患者需要几个月的时间，这会导致 诊断并阻止治疗的开始。迫切需要一种廉价、易于使用的测试， 靶向疾病的遗传基础，并能迅速提供结果，以便启动准确的治疗 立即在护理点。 为了满足这一需求，我们将开发一种快速、廉价的基于核酸的检测方法， 导致SCD的β珠蛋白基因突变：βS（Glu 6Val）和βC（Glu 6Lys）。我们提出了一个测试， 区分以下临床相关基因型：1）SCD患者（βSβS：SS，βSβC：SC）; 2）未受影响的 个体（βAβA：AA）; 3）SCD携带者（βAβS：AS，βAβC：AC）;和4）血红蛋白C病（βCβC：CC）。因为 输血含有来自捐献者的球蛋白，核酸检测是检测婴儿的唯一可能性。 以及最近接受过输血的儿童。一种廉价的即时检测， 在所有患者中检测SCD将极大地改善对患有SCD的儿童的护理。 我们的目标是：（1）设计并验证第一个用于镰状细胞的基因床旁核酸扩增测试 可以用于最近输血的患者的疾病;（2）在低成本的、可制造的、 完全集成的样本到答案平台;（3）评估两个测试的灵敏度，特异性和可用性 试点临床研究。 我们在莱斯大学、贝勒医学院和马拉维利隆圭的卡穆祖中心医院的团队， 生物工程和临床诊断方面的必要专业知识，以应对诊断SCD的挑战 在资源有限的环境中。我们提出的检测方法符合以下条件下即时检测的最佳要求： 中低收入国家。最后，它将消除目前与样品运输或输血相关的长时间延迟， 将筛查阳性的患者送到检测中心，并立即开始对婴儿的治疗， 诊断为SCD的儿童。