AFFORDABLE RAPID BACTERIAL DETECTION IN STORED PLATELETS

描述（由申请人提供）：采集用于输血的血小板必须在室温下储存，以最大限度地提高其在功能状态下的存活率。在采集过程中或由于供体中未注意到的菌血症，细菌可能被引入储存的血小板中;室温储存比其他血液成分使用的较低储存温度更有利于更多细菌种类的生长。污染的风险将血小板的有效期限制为5天，尽管已经确定无污染的单位保持有效至少7天。经批准的细菌检测方法需要对测试样品进行孵育，通常为24小时，缩短了有效保质期。尽管已经证明使用基于荧光的成像细胞术直接检测储存的血小板中的细菌，但是到目前为止，所需的设备太昂贵而不具有成本效益。然而，电光技术的最新进展，特别是高强度发光二极管（LED）和高效的电荷耦合器件相机（CCD），现在使生产简单的自动荧光图像细胞仪成为可能，售价低于10，000美元，可能在临床上有用。本项目将证明该仪器能够检测和计数接种到血小板单位中的浓度低至100个菌落形成单位（CFU）/mL的常见细菌污染物，使用核酸染料和其他荧光试剂染色和识别血小板和其他血液有形成分的洗涤剂裂解后浓缩在膜滤器上的微生物，检测时间约为1小时。

DESCRIPTION (provided by applicant): Blood platelets collected for transfusion must be stored at room temperature to maximize their survival in a functional state. Bacteria may be introduced into stored platelets during the collection process or as a result of unnoticed bacteremia in the donor(s); room temperature storage is substantially more conducive to the growth of more bacterial species than are the lower storage temperatures used for other blood components. The risk of contamination limits platelet shelf life to 5 days, although it has been established that contamination-free units remain effective for at least 7 days. Approved methods of bacterial detection require incubation of the test sample, typically for 24 hours, shortening effective shelf life. Although direct detection of bacteria in stored platelets has been demonstrated using fluorescence-based imaging cytometry, the required apparatus has, to the present, been too expensive to be cost-effective. However, recent advances in electro-optic technology, notably high-intensity light-emitting diodes (LEDs) and efficient charge-coupled device cameras (CCDs), now make it feasible to produce simple automated fluorescence image cytometers, salable for well under $10,000, that could be clinically useful. This project will demonstrate the capacity of such apparatus to detect and count common bacterial contaminants seeded into platelet units at concentrations as low as 100 colony forming units (CFU)/mL, using nucleic dyes and other fluorescent reagents to stain and identify organisms concentrated onto membrane filters following detergent lysis of platelets and other formed elements of blood, with a detection time on the order of one hour.