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The biological properties of therapeutic peptides, such as their pharmacokinetics and pharmacodynamics, are correlated with their structure and aggregation properties. Herein, we studied the aggregation properties of a therapeutic peptide (CIGB-814), currently in phase 2 clinical trial, for the treatment of rheumatoid arthritis over a wide range of concentrations (µM–mM). We applied spectroscopic techniques (fluorescence, circular dichroism, resonance, and dynamic light scattering), atomic force microscopy, and molecular dynamics simulations to determine the aggregation mechanism of CIGB-814. We found that the hierarchical aggregation of CIGB-814 at micromolar concentrations was initiated by the formation of peptide oligomers. Subsequently, the peptide oligomers trigger the nucleation and growth of peptide nanostructures (cac = 123 µM), ultimately leading to the fibrillization of CIGB-814 (cac’ = 508 µM). These results pave the way for a deeper understanding of the CIGB-814 therapeutic activity and may give important insights on its pharmacokinetics.

Made available in DSpace on 2018-12-11T17:16:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Molecular cross-reactivity caused by allergen homology or cross-reactive carbohydrate determinants (CCDs) is a major challenge for diagnosis and immunotherapy of insect venom allergy. Venom phospholipases A1 (PLA1s) are classical, mostly non-glycosylated wasp and ant allergens that provide diagnostic benefit for differentiation of genuine sensitizations from cross-reactivity. As CCD-free molecules, venom PLA1s are not causative for CCD-based cross-reactivity. Little is known however about the protein-based cross-reactivity of PLA1 within vespid species. Here, we address PLA1-based cross-reactivity among ten clinically relevant Hymenoptera venoms from Neotropical and temperate regions including Polybia paulista (paulistinha) venom and Vespula vulgaris (yellow jacket) venom. In order to evaluate cross-reactivity, sera of mice sensitized with recombinant PLA1 (rPoly p 1) from P. paulista wasp venom were used. Pronounced IgE and IgG based cross-reactivity was detected for wasp venoms regardless the geographical region of origin. The cross-reactivity correlated well with the identity of the primary sequence and 3-D models of PLA1 proteins. In contrast, these mice sera showed no reaction with honeybee (HBV) and fire ant venom. Furthermore, sera from patients monosensitized to HBV and fire ants did not recognize the rPoly p 1 in immunoblotting. Our findings reveal the presence of conserved epitopes in the PLA1s from several clinically relevant wasps as major cause of PLA1-based in vitro cross-reactivity. These findings emphasize the limitations but also the potential of PLA1-based HVA diagnostics. Laboratório de Biologia Molecular de Artrópodes-LBMA-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, n_1515, Bela Vista Laboratório de Imunologia Translacional Faculdade de Ciências Médicas FCM Universidade Estadual de Campinas-UNICAMP, Rua Vital Brasil, n_ 300, Cidade Universitária “Zeferino Vaz” Center for Genetic Engineering and Biotechnology Biomedical Research Division System Biology Department, Ave. 31, e/158 and 190, P.O. Box 6162, Cubanacan, Playa Centro de Estudos de Insetos Sociais-CEIS-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, n° 1515, Bela Vista Immunological Engineering Department of Engineering Aarhus University, Gustav Wieds Vej 10 Euroimmun AG, Seekamp 21 Centro de Estudos de Venenos e Animais Peçonhentos-CEVAP (Univ Estadual Paulista), Rua José Barbosa de Barros, 1780, Fazenda Experimental Lageado Laboratório de Biologia Molecular de Artrópodes-LBMA-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, n_1515, Bela Vista Centro de Estudos de Insetos Sociais-CEIS-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, n° 1515, Bela Vista Centro de Estudos de Venenos e Animais Peçonhentos-CEVAP (Univ Estadual Paulista), Rua José Barbosa de Barros, 1780, Fazenda Experimental Lageado FAPESP: 2013/26451-9

Made available in DSpace on 2018-12-11T17:07:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-12-15 Polybia paulista (Hymenoptera: Vespidae) is a clinically relevant social wasp that frequently causes stinging accidents in southeast Brazil. To date, diagnosis and specific immunotherapy (SIT) of allergy are based on the use of crude venom extracts. Production of recombinant forms of major allergens from P. paulista venom will improve diagnosis and SIT of allergic patients by reducing the incidence of cross-reactivity and non-specific sensitization. Here, we describe the molecular cloning, heterologous expression, purification and IgE-mediated immunodetection of phospholipase A1 (Poly p 1), a major allergen from P. paulista venom. The cDNA of Poly p 1 was extracted from venom glands and then cloned, and further expression of the recombinant allergen (rPoly p 1) was achieved in Escherichia coli BL21 (DE3) cells. Purification of rPoly p 1 was performed using immobilized Ni2+ metal affinity chromatography. Also, a single-step chromatographic method allowed the purification of native Poly p 1 (nPoly p 1) from the wasp's venom glands. We used western blotting to evaluate IgE-reactivity of the sera from 10 P. paulista venom-allergic patients to rPoly p 1 and nPoly p 1. High levels of insoluble rPoly p 1 were obtained during heterologous expression. After solubilization of inclusion bodies and purification of the recombinant protein, a unique band of ∼34 kDa was detected in SDS-PAGE analysis. Allergen-specific IgE (sIgE) from allergic patients' sera recognized rPoly p 1, nPoly p 1 and crude venom extract to a similar extent. Our results showed that rPoly p 1 could be used for development of component-resolved diagnosis (CRD) and molecular-defined SIT of P. paulista venom allergy. Laboratório de Biologia Molecular de Artrópodes-LBMA-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, nº 1515, Bela Vista, CEP Laboratório de Mutagênese Ambiental, Avenida 24-A, nº 1515, Bela Vista, CEP Center for Genetic Engineering and Biotechnology Biomedical Research Division System Biology Department, Ave. 31, e/ 158 and 190, P.O. Box 6162, Cubanacan Laboratório de Imunologia Translacional Faculdade de Ciências Médicas FCM Universidade Estadual de Campinas-UNICAMP, Rua Vital Brasil, nº 300, Cidade Universitária “Zeferino Vaz”, CEP Centro de Estudos de Insetos Sociais-CEIS-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, nº 1515, Bela Vista, CEP Instituto de Pesquisa em Bioenergia (IPBEN) (Univ Estadual Paulista), Av. 24-A, nº1515, Bela Vista, CEP Centro de Estudos de Venenos e Animais Peçonhentos-CEVAP (Univ Estadual Paulista), Rua José Barbosa de Barros, 1780, Fazenda Experimental Lageado Laboratório de Biologia Molecular de Artrópodes-LBMA-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, nº 1515, Bela Vista, CEP Centro de Estudos de Insetos Sociais-CEIS-IBRC-UNESP (Univ Estadual Paulista), Av. 24-A, nº 1515, Bela Vista, CEP Instituto de Pesquisa em Bioenergia (IPBEN) (Univ Estadual Paulista), Av. 24-A, nº1515, Bela Vista, CEP Centro de Estudos de Venenos e Animais Peçonhentos-CEVAP (Univ Estadual Paulista), Rua José Barbosa de Barros, 1780, Fazenda Experimental Lageado

CIGB-552 is a cell-penetrating peptide that exertsin vitroandin vivoantitumor effect on cancer cells. In the present work, the mechanism involved in such anticancer activity was studied using chemical proteomics and expression-based proteomics in culture cancer cell lines. CIGB-552 interacts with at least 55 proteins, as determined by chemical proteomics. A temporal differential proteomics based on iTRAQ quantification method was performed to identify CIGB-552 modulated proteins. The proteomic profile includes 72 differentially expressed proteins in response to CIGB-552 treatment. Proteins related to cell proliferation and apoptosis were identified by both approaches. In line with previous findings, proteomic data revealed that CIGB-552 triggers the inhibition of NF-κB signaling pathway. Furthermore, proteins related to cell invasion were differentially modulated by CIGB-552 treatment suggesting new potentialities of CIGB-552 as anticancer agent. Overall, the current study contributes to a better understanding of the antitumor action mechanism of CIGB-552.