First Author | Xia M | Year | 2013 |
Journal | PLoS One | Volume | 8 |
Issue | 12 | Pages | e81056 |
PubMed ID | 24349031 | Mgi Jnum | J:211155 |
Mgi Id | MGI:5574163 | Doi | 10.1371/journal.pone.0081056 |
Citation | Xia M, et al. (2013) Immunization of Chlamydia pneumoniae (Cpn)-infected Apob(tm2Sgy)Ldlr(tm1Her)/J mice with a combined peptide of Cpn significantly reduces atherosclerotic lesion development. PLoS One 8(12):e81056 |
abstractText | OBJECTIVE: To investigate the antigenic effect of a peptide containing two epitopes of Chlamydia pneumoniae (Cpn) on atherosclerotic lesion formation in mice infected with Cpn. MATERIALS AND METHODS: Six-week-old Apob(tm2Sgy)Ldlr(tm1Her)/J mice were immunized using a repetitive immunization multiple-sites strategy with KLH-conjugated peptides derived from the major outer membrane protein and the putative outer membrane protein 5 of Cpn. Mice were fed a high-fat diet and infected with Cpn twice during the 10-week diet period. Lesions were evaluated histologically; local and systemic immune responses were analyzed by immunohistochemistry of aorta samples and cytokine measurements in plasma samples and splenocyte supernatants. RESULTS: Mice immunized with the combined Cpn peptide showed a greater reduction in lesion size compared to mice immunized with either epitope alone [54.7% vs 39.8% or 41.72%] and was also associated with a significant decrease in lesion area in descending aortas compared with those in controls (88.9% for combined Cpn peptide, 81.9% for MOMP peptide and 75.7% for Omp5, respectively). This effect was associated with a shift in the cellular composition of plaques towards decreased inflammatory cell and increased regulatory T-cell content. Additionally, the effect was also connected with decreased secretion of proinflammatory cytokines and increased production of anti-inflammatory cytokines demonstrated in plasma and in supernatant on stimulated spleen cells. CONCLUSIONS: Atherosclerotic lesion formation may be promoted by Cpn infection in the presence of a high-fat diet, and reduced by immunization with the combined Cpn peptide. The combined peptide has more potential than either epitope alone in reducing atherosclerotic lesion development through Treg expansion. |