title: Design of immunogenic peptides from Mycobacterium tuberculosis genes expressed during macrophage infection.
abstract: In vitro diagnosis of MTB-infection uses MTB-proteins coded for by genes of the region of differentiation 1 (RD1) of the MTB genome. This study wants to test if proteins preferentially expressed during MTB-intracellular growth might provide new targets for the diagnosis of MTB-infection. To this end seventy-five multiepitopic HLA-promiscuous MTB-peptides were designed by quantitative implemented peptide-binding motif analysis from 3 MTB-protein genes expressed in activated human macrophages (MA), 4 genes expressed during growth in non-activated human macrophages (MN-A), 12 housekeeping genes (HKG) and 6 genes of the RD1 region (RD1) as control. ELISpot for IFN-was performed to measure the responses of PBMCs deriving from 45 patients affected by active tuberculosis and 34 controls. In active-TB patients, the mean response to RD1-derived peptides was higher than that to either MA (p<0.01), MN-A (p<0.008) or HKG (p<0.01) derived peptides. In TST-positive subjects all selected peptides elicited significant IFN-T-cell responses (p<0.02 compared to TST-negatives), but without differences between the subgroups. Further, T-cell responses to RD1 peptides were lower in the 23 active-TB treated patients than in the untreated ones (p<0.01). The response to MA peptides in treated active-TB was higher than when untreated (p<0.01). These results demonstrate that the use of in vitro models of MTB-intracellular infection to select MTB gene products for further in silico and in vitro assessment of their immunogenicity have the potential to identify novel antigens amenable to the design of new tools for diagnosis and monitoring of tuberculosis.
authors.affiliation: Department of Internal Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy. fseghrouchni@yahoo.fr
authors.forename: Fouad
authors.initials: F
authors.lastname: Seghrouchni
authors.forename: Silvia
authors.initials: S
authors.lastname: Contini
authors.forename: Roumiana
authors.initials: R
authors.lastname: Markova
authors.forename: Roumiana
authors.initials: R
authors.lastname: Drenska
authors.forename: Khalid
authors.initials: K
authors.lastname: Sadki
authors.forename: Larbi
authors.initials: L
authors.lastname: Baassi
authors.forename: Larbii
authors.initials: L
authors.lastname: Baassi
authors.forename: Yana
authors.initials: Y
authors.lastname: Todorova
authors.forename: Velislava
authors.initials: V
authors.lastname: Terzieva
authors.forename: Marialuisa
authors.initials: M
authors.lastname: Bocchino
authors.forename: Giulia
authors.initials: G
authors.lastname: Cappelli
authors.forename: Alfonso Maria
authors.initials: AM
authors.lastname: Altieri
authors.forename: Mario Giuseppe
authors.initials: MG
authors.lastname: Alma
authors.forename: Abdelaziz
authors.initials: A
authors.lastname: Benjouad
authors.forename: Francesca
authors.initials: F
authors.lastname: Mariani
authors.forename: Bogdan
authors.initials: B
authors.lastname: Petrunov
authors.forename: Vittorio
authors.initials: V
authors.lastname: Colizzi
authors.forename: Rajae
authors.initials: R
authors.lastname: El Aouad
authors.forename: Cesare
authors.initials: C
authors.lastname: Saltini
authors.forename: Massimo
authors.initials: M
authors.lastname: Amicosante
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000235:genetics* / Q000276:immunology; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D055985:Latent Tuberculosis / Q000175:diagnosis / Q000276:immunology; D008264:Macrophages / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D010455:Peptides / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D020539:Sequence Analysis, Protein; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D015415:Biomarkers; D010455:Peptides; D007371:Interferon-gamma