[Research on human enterovirus 71 infectivity assay based on a real-time cell analysis]

This research aims to evaluate the application of Real - time cell assay (RTCA) based on microelectronics sensor technology in the detection of HEV71 induced cell lesion. Growth indexes of RD cells at different stages were observed dynamically, appropriate cell concentration was selected to test HEV71 infectivity and to determine the HEV71 neutralizing antibody titer in serum. The traditional microplate test was used as methodology comparison and results validation at the same time. Cell impedance was transformed to cell index (CI) value and visual dynamic curve through software, and the result showed that the observation of HEV71 infectivity was more than 5d when the RD cells concentration was 1. 5 X 10(4) hole on the 96 electronic orifice plate. Compared with the traditional cytopathic effect (CPE) through microscope observation method, the end point judgment results were consistent between these two methods at 132h (about 5. 5d) post virus inoculation. In the neutralization tests, three CI values of neutralizing antibody titers against HEV71 in human serum were correspond to those obtained from traditional 96 microplate microscopy. RTCA also suggested that the presentation time of CPE induced by the i virus could be different even the end point judgment was the same with the same neutralization antibody titer. Compared with the traditional microplate monitoring method, RTCA can save labor and eliminate the hands-on error in the monitoring HEV71 infectivity and antibody titer detection in serum. RTCA can be served as one of the supplementary methods of traditional detection method, with the advantages of dynamically observing the occurrence and development of cell pathological changes, and the variation of virus infectivity and serum neutralizing antibodies.