AUTHOR=Pang Yulian , Shui Jingwei , Li Changchang , Li Yongzhi , Chen Hongliang , Tang Shixing 

TITLE=The serodiagnositic value of Chlamydia trachomatis antigens in antibody detection using luciferase immunosorbent assay

JOURNAL=Frontiers in Public Health

VOLUME=12

YEAR=2024

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2024.1333559

DOI=10.3389/fpubh.2024.1333559

ISSN=2296-2565

ABSTRACT=<sec><title>Introduction</title><p>Among the different antigens used in the detection of anti-<italic>Chlamydia trachomatis</italic> antibodies, significant differences in sensitivity and specificity have been observed. Further evaluation of <italic>C. trachomatis</italic> antigens in antibody detection is urgently needed for the development and application of <italic>C. trachomatis</italic> serologic assays.</p></sec><sec><title>Methods</title><p><italic>Chlamydia trachomatis</italic> antigens Pgp3, TmeA, InaC, and HSP60 were selected and used in luciferase immunosorbent assay (LISA). The detection results obtained from well-defined <italic>C. trachomatis</italic> positive and negative samples were compared with the commercial <italic>C. trachomatis</italic> ELISA (Mikrogen) for performance evaluation.</p></sec><sec><title>Results</title><p>Pgp3, TmeA, InaC, and HSP60-based LISA showed sensitivity of 92.8, 88.8, 90.4, and 94.4%, and specificity of 99.2, 99.2, 99.2, and 92%, respectively. ROC analysis indicated that Pgp3-based LISA showed similar performance to Mikrogen ELISA (AUC 0.986 vs. 0.993, p = 0.207). Furthermore, four <italic>C. trachomatis</italic> antigens achieved strong diagnostic efficiency, i.e., positive likelihood ratios [+LR] ≥ 10 in <italic>C. trachomatis</italic>-infected women and negative likelihood ratios [−LR] ≤ 0.1 in <italic>C. trachomatis</italic> negative low exposure risk children, but only Pgp3 and TmeA showed strong diagnostic value in general adults. In addition, Pgp3, TmeA, and InaC, but not HSP60, achieved high performance, i.e., both positive predictive value (PPV) and negative predictive value (NPV) ≥ 90.9%, and showed no significant cross-reactivity with anti-<italic>Chlamydia</italic><italic>pneumoniae</italic>.</p></sec><sec><title>Conclusion</title><p>Three <italic>C. trachomatis</italic> species-specific antigens Pgp3, TmeA, and InaC show superior performance in the detection of anti-<italic>C. trachomatis</italic> antibody, indicating the potential to be used in developing <italic>C. trachomatis</italic> serologic tests.</p></sec>