| dc.description.abstract | English Abstract
Backgrounds: Cervicovaginitis is a common infection in women. Ignorance of this disease may place a heavy burden on female and neonatal health due to occurrence of severe sequelae such as female infertility, ectopic pregnancy, chronic pelvic pain, and neonatal infections. Prompt and appropriate antibiotic treatment can cure infection and avoid complications. However, adequate treatment is not easy, since many factors can interfere with an early and rapid identification of various pathogens from complicated mixed micro-flora of the vagina and cervix. Among these factors, a non-user-friendly rapid detection system seems the most important. A microarray immunoassay chip was fabricated for binding of pathogens causing cervicovaginitis and a signal amplifying system using liposomal nanovesicles was used for detection. Laboratory and clinical samples were tested with some promising results. We collected the source from Veteran General Hospital in Taipei and Hit Laboratory in the department of Systems Biology and Bio-informatics. With expert help from Statistic school of National Central University, our project was accepted and granted by the aiwan Joint Research Program (VGHUST99-G4-3) from Jan. 1st to Dec. 31st, 2010. Although the attempt to simulate a normal and symptomatic micro-flora in the vagina by mathematic model demanded more work from laboratory and clinic setting. We still finished the project with limited resources and published two SCI manuscripts and submitted our third one.
Material and methods: After literature review and data mining on the internet, five pathogens were chosen based on our limited culture ability and financial support. Well established capture antibodies for specific pathogens causing cervicovaginitis, including Streptococcus B, Chlamydia trachomatis , Neisseria gonorrhoeae , Escherichia coli, and anti Candida albicans were purchased to be printed on a Chip. Signal amplifying system using liposomal nanovesicles was established and validated. Various pathogens and antigens were collected for validation of this detecting system on chips. Cervical and vaginal samples were obtained from an ordinary gynecologic clinic for pathogens detection. Spiking of candida in the samples were used to testify the usefulness of this detection system. We will use the proportional odds models to make inferences regarding which pathogen tends to induce more severe infection if more positive data available. The difference between positive and negative readings was evaluated by paired t test.
Results: During our literature review and data mining for the application of our tool in the diagnosis of specific infections, we focused on the gonococcal infection first. After comparison with other tools, we argued the best method for the diagnosis of gonorrhea infection is still under construction especially regarding the qualities as a Point-of-Care tool. Furthermore, our system was proved to be sensitive in detecting Chlamydia antigen to a level of micro-gram. A positive proportion relationship between antigen concentrations and signal intensity was also demonstrated. Another review about the possibility of our system and comparison with other tools for diagnosis of Chlamydia infection was completed and published. As for other pathogens, the power of this system was validated (p<0.01). The detection sensitivity of candida of this system reach the level of 100,000 CFU/ml in a vaginal sample. In the study of clinical samples, the sensitivity and specificity of this tool in the candida spike test reach near 100% sensitivity and specificity. Moreover, the average processing time is around 200 minutes and the required apparatus is ordinary laboratory equipments with a fluorescent reading machine.
Conclusions: Microarray chip is a relatively rapid, easy, inexpensive and sensitive tool to detect many pathogens, at least for Candida, in a one-time vaginal sampling process in our Laboratory. Eventually, advances in related laboratory techniques will satisfy our needs to detect pathogens in vaginal and cervical samples economically and instantly.
| en_US |