Immunogenecity studies of type Ⅲ secretory system proteins in Chlamydia trachomatis

• Main Authors: Pei-Yi Tsai, 蔡佩宜
• Other Authors: Shu-Ying Li
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/29662403351609651554

碩士 === 國立陽明大學 === 生物藥學研究所 === 93 === Chlamydia trachomatis is an obligate intracellular pathogen of humans, primarily causing infections in ocular and urogenital epithelial cells and resulting in various symptoms. Among all sexually transmitted diseases (STD), C. trachomatis has surpassed Gonorrhea and Syphilis to become the most important STD worldwide, especially in Southeast Asia. Up to this point, there is no vaccine against C. trachomatis. Furthermore, most patients remain asymptomatic after infection; therefore, both epidemiological screening and public health education are pivotal for prevention and control of C. trachomatis infections. The aim of this study is to develop immunological methods for the detection of the antigen or antibody of a C. trachomatis specific type III secretory protein IncA in 3 kinds of clinical specimens and to evaluate the clinical applicability of the IncA-based immunological detection methods. In serum sample, IgA-based antibody response to IncA was detected. In urine and genital swab samples, 50% and 70% antibody response was also detected, respectively. This indicates that IncA antibody detection can serve as a useful supplement of the existing detection methods, especially for genital swab samples. This may be owing to the fact that the urogenital epithelium is the primary site of infection for C. trachomatis, and thus stronger antibody response can be induced for genital swab samples. With respect to IncA antigen detection, antigen was detected in urine samples of 23% patient while in genital swab samples, none was detected. Therefore, urine samples are superior to genital swab samples for antigen detection. It may be inferred that the acidic environment of the genital tract denatures protein antigen; on the other hand, the pH value of urine is approximately neutral, which is more suitable for antigen. As a whole, urine and genital swab samples are more suitable than serum samples for C. trachomatis detection. In conclusion, the potential applicability of IncA protein in the detection of C. trachomatis antigen and antibody was found. Further studies are needed, such as evaluation of the sensitivity and specificity of the methods and comparison with commercial diagnostic kits to validate the clinical applicability of IncA protein-based immunological detection methods inr the diagnosis of C. trachomatis.