Chlamydia pneumoniae genome sequence analysis and identification of HLA-A2-restricted CD8+ T cell epitopes recognized by infection-primed T cells.

In the present study, we performed in silico analysis of Chlamydia pneumoniae genome sequence to identify human HLA-A2-restricted T cell epitopes. Thirty-one Chlamydia-specific protein antigens were selected and peptides were derived thereof using an HLA-A2 epitope predictive algorithm. Firstly, we tested binding of 55 selected 9mer peptides to HLA-A2 in vitro.

Inhibition of cell proliferation and induction of apoptosis by novel tetravalent peptides inhibiting DNA binding of E2F.

We have isolated several peptides from random peptide phage display libraries that specifically recognize the cell cycle regulatory transcription factor E2F and inhibit DNA binding of E2F/DP heterodimers (E2F-1, E2F-2, E2F-3, E2F-4 or E2F-5, and DP-1). The inhibitory efficiency could be strongly enhanced by generating branched tetravalent molecules. To analyse the biological consequences of peptide-mediated E2F inhibition, we fused two of these branched molecules to a cell-penetrating peptide derived from the HTV-Tat protein.

Genomic approach for analysis of surface proteins in Chlamydia pneumoniae.

Chlamydia pneumoniae, a human pathogen causing respiratory infections and probably contributing to the development of atherosclerosis and heart disease, is an obligate intracellular parasite which for replication needs to productively interact with and enter human cells. Because of the intrinsic difficulty in working with C. pneumoniae and in the absence of reliable tools for its genetic manipulation, the molecular definition of the chlamydial cell surface is still limited, thus leaving the mechanisms of chlamydial entry largely unknown.