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。细菌可能在采集过程中或由于献血者未被注意到的菌血症而进入储存的血小板(S)；与用于其他血液成分的较低温度储存相比，室温储存更有利于更多细菌的生长。污染的风险将血小板的保质期限制在5天内，尽管已经确定无污染的设备至少可以保持7天的有效期。经批准的细菌检测方法需要对测试样本进行培养，通常为24小时，从而缩短有效保质期。尽管基于荧光的成像细胞术已经证明了直接检测储存的血小板中的细菌，但到目前为止，所需的仪器太昂贵了，不划算。然而，最近电光技术的进步，特别是高强度发光二极管(LED)和高效电荷耦合设备相机(CCD)，现在使生产简单的自动化荧光图像细胞仪成为可能，售价远低于1万美元，可能会在临床上使用。该项目将展示这种仪器的能力，以检测和计数浓度低至100个集落形成单位(CFU)/毫升的血小板单位的常见细菌污染物，使用核酸染料和其他荧光试剂染色和识别在洗涤剂溶解血小板和其他血液形成元素后聚集在膜过滤器上的微生物，检测时间约为一小时。

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.