Recombinant Chlamydia trachomatis MOMP protein (a.a. 66-165) [His]

Numerous Chlamydia trachomatis proteins have been identified as potential subunit vaccines, of which the major outer-membrane protein (MOMP) has, so far, proven the most efficacious. Recently, subunit A of the V-type ATP synthase (ATPase; TC0582) complex was shown to elicit partial protection against infection. Computational modeling of a neighboring gene revealed a novel subunit of the V-type ATPase (TC0583). To determine if this newly identified subunit could induce protection and/or enhance the partial protection provided by subunit A alone, challenge studies were performed using a combination of these recombinant proteins. The TC0583 subunit alone and concurrently with TC0582, was used to vaccinate BALB/c mice utilizing CpG-1826 and Montanide ISA 720 VG as adjuvants. Vaccinated animals were challenged intranasally with Chlamydia muridarum and the course of the infection was followed. Mice immunized with individual antigens showed minimal alleviation of body weight reduction; however, mice immunized with TC0583 and TC0582 in combination, displayed weight loss levels close to those observed with MOMP. Importantly, immunization with a combination of recombinant subunit proteins reduced chlamydial inclusion forming units by approximately a log-fold. These protection levels support that, these highly conserved Chlamydia proteins, in combination with other antigens, may serve as potential vaccine candidates. (C) 2015 Published by Elsevier Masson SAS on behalf of Institut Pasteur.

Objective. To search for molecular evidence of Chlamydial infection in system lupus erythematosus (SLE) subjects and to assess if there is an association of this infectious agent with coronary artery calcification (CAC), a marker of total atherosclerotic burden. Methods. 28 SLE subjects had blood samples drawn and DNA extracted from peripheral blood mononuclear cells (PBMC) and oil electron beam computed tomography (EBCT) scan. Polymerase chain reaction (PCR) analysis was performed for Chlamydia trachomatis 16srRNA and major outer membrane protein (MOMP) and for C. pneumoniae 16srRNA, MOMP, as well as nested PCR for MOMP. Results. Four of 28 subjects (14.2%) had evidence of C. pneumoniae nucleic acid in PBMC. The 16srRNA primers detected C. pneumoniae in one patient (3.57%) and the nested PCR MOMP primers in 3 subjects (10.71%). None were positive for Chlamydia trachomatis. Two of the 4 subjects with C. pneumoniae DNA had abnormal EBCT scans and 2/11 (18.3%) subjects with abnormal EBCT were positive for C. pneumoniae. There were significant associations of C. pneumoniae DNA with smoking (OR = 3) and corticosteroid use. The odds ratio for subjects with abnormal CAC and detectable C. pneumoniae was 1.67. Conclusion. This pilot study demonstrates for the first time that C. pneumoniae DNA call be identified in the PBMC of some SLE subjects and there may be all association with CAC. Smoking may be an additional risk factor for infection in this population. Determination of pathogenicity of this organism in atherosclerotic coronary vascular disease in SLE will require further study.