title: Immunogenic peptides: B & T Cell Epitopes of Per a 10 Allergen of Periplaneta americana.
abstract: Mapping of B and T cell epitopes of an allergen can be utilised in the development of alternative therapeutic modalities and diagnostics. The present study was aimed to identify B and T cell epitopes of Per a 10, a major cockroach allergen, by computational tools and subsequent validation by in vitro experiments. Per a 10 three-dimensional structure was homology modelled using structure of anionic trypsin from pacific chum salmon as a template. Seven B cell epitopes (B-P1 to B-P7) were predicted by sequence and structure based methods. Three T cell epitopes (T-P8 to T-P10) were predicted by binding score and inhibitory concentration dependent prediction tools. Predicted epitopes were synthesized and biological activity was assessed by ELISA, ELISA inhibition and PBMC proliferation assays. B cell peptides B-P5, B-P6 and B-P7 showed significantly high IgE binding with pooled and individual cockroach hypersensitive patients' sera while the T cell peptides did not show IgE binding. ELISA inhibition was performed to determine the potency of the predicted peptides. Fifty nanogram of peptide B-P7 was required for 50% IgE binding inhibition of surface bound Per a 10 whereas seventy five nanogram and ninety nanogram of B-P5 and B-P6 were required for the same respectively. Upon stimulation with T-P8 and T-P10 peptides, PBMCs from cockroach allergic patients' (n = 15) showed significant lymphocyte proliferation and induced IL-4 and IL-5 cytokine release in the culture supernatant demonstrating Th2 dominant cell mediated response of predicted T cell peptides. In conclusion, Per a 10 3-D structure obtained by homology modelling was used to identify B and T cell epitopes, followed by in vitro validation. The identified peptides can be potentially used in designing diagnostics and therapies for cockroach allergy.
authors: CSIR-Institute of Genomics and Integrative Biology, Delhi, India; Academy of Scientific & Innovative Research (AcSIR), CSIR-IGIB, Mall road, Delhi, India.
authors: Dhanapal
authors: D
authors: Govindaraj
authors: CSIR-Institute of Genomics and Integrative Biology, Delhi, India; Academy of Scientific & Innovative Research (AcSIR), CSIR-IGIB, Mall road, Delhi, India.
authors: Swati
authors: S
authors: Sharma
authors: Department of Pulmonary Medicine, V.P. Chest Institute, Delhi, India.
authors: S N
authors: SN
authors: Gaur
authors: USLavasa Medical and Research Center, Chandigarh, India.
authors: Shakuntala
authors: S
authors: Lavasa
authors: Bengaluru Allergy Centre, Bangalore, India.
authors: Nagendra
authors: N
authors: Prasad
authors: CSIR-Institute of Genomics and Integrative Biology, Delhi, India. Electronic address: naveen@igib.res.in.
authors: Naveen
authors: N
authors: Arora
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D003198:Computer Simulation; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D018985:Epitopes, B-Lymphocyte / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology; D019476:Insect Proteins / Q000737:chemistry / Q000276:immunology*; D008958:Models, Molecular; D010526:Periplaneta / Q000276:immunology
chemical_list: D000485:Allergens; D018985:Epitopes, B-Lymphocyte; D018984:Epitopes, T-Lymphocyte; D019476:Insect Proteins
keywords: B cell epitopes; IgE; In silico; Peptides; Per a 10; T cell epitopes