Obtaining an ELISA test based on a recombinant protein of Chlamydia trachomatis

Abstract

Chlamydia trachomatis is considered as a public health problem due to its high prevalence and increased rates of gynecological disorders. The major outer membrane protein (MOMP) of this bacterium is the most abundant protein in its membrane and has been evaluated not only as a vaccine development candidate but also is used in many diagnostic tests. The MOMP weighs 69 kDa and contains four variable segments (VS 1-4) separated by constant regions. Several research groups have developed recombinant single-variable segments of MOMP expressed in Escherichia coli cytoplasm. But, all variable segments have been used minimally for the diagnosis of a chlamydial infection. In this experiment, the authors obtained the recombinant MOMP of C. trachomatis (rMOMP) in E. coli rMOMP and extracted, purified, and partially characterized it. This was later used to identify anti-Chlamydia trachomatis antibodies in sera of infertile patients by immunodetection assays, enzyme-linked immunosorbent assay (ELISA), and indirect immunofluorescence tests. The ELISA test showed high sensitivity and low specificity of 100 and 58.3%, respectively. The above results obtained were linked to the cross-reactivity of antibodies against C. pneumoniae or C. psittaci. Hence, an evaluation was performed to obtain an optimized test for the diagnosis of C. trachomatis infection.

FastProtein – An automated software forin silicoproteomic analysis

“…FastProtein integrates calculations of molecular weight, isoelectric point, hydropathy, and aromaticity with predictions of subcellular location, transmembrane domains, signal peptide and GPI-anchor, GO, endoplasmic reticulum retention, and N-glycosylation domains, as well as analyses using InterProScan, PANTHER, PFam, and alignment-based annotation searches. Additionally, the software provides a dataset of proteins with evidence of membrane localization, which is important for immunogenicity studies during vaccine development (Cheng et al, 2021; Kis et al, 2018) and diagnostic tools, such as ELISA (de Haro-Cruz et al, 2019; Iha et al, 2022) and western blotting (Begum et al, 2022; Crescitelli et al, 2021; Springhorn & Hoppe, 2019).…”

Chlamydia trachomatis as a Current Health Problem: Challenges and Opportunities

“…In addition, serological tests that are based on the quantification of IgG, IgA, and IgM were developed using commercial ELISA (enzyme-linked immunosorbent assay) kits, namely RIDASCREEN ® Chlamydia trachomatis, KGM2901, (R-Biopharm, Darmstadt, Germany) through serum samples, determining the ratios of the immunoglobulins of interest [ 63 , 64 ]. These serological approaches are associated with low specificity, and some authors also defend that seropositivity was not associated with active infection [ 65 , 66 ]. Currently, the most suitable Chlamydia trachomatis detection method is based on NAAT.…”

Multi-repeat sequences identification using genome mining techniques for developing highly sensitive molecular diagnostic assay for the detection of Chlamydia trachomatis

“…Enzyme linked immuno-sorbent assays that detect bacterial lipopolysaccharide may cross-react with other gram negative bacteria, which may give false-positive results. The C. trachomatis antibody response may be absent or delayed in some patients, which makes many serological tests inaccurate 15 . In addition, most of the C. trachomatis infections are asymptomatic and are diagnosed late, resulting in uninterrupted transmission 16 .…”