Navegando por Palavras-chave "Hemocytes"

Agora exibindo 1 - 3 de 3
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Biochemical characterization of a Kunitz type inhibitor similar to dendrotoxins produced by Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) hemocytes
    (Elsevier B.V., 2010-02-10) Lima, Cassia A. [UNIFESP]; Torquato, Ricardo J. S. [UNIFESP]; Sasaki, Sergio D. [UNIFESP]; Justo, Giselle Z. [UNIFESP]; Tanaka, Aparecida S. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)
    A novel chymotrypsin inhibitor identified in fat body and hemocyte cDNA libraries of Boophilus microplus was named BmCI (B. microplus Chymotrypsin Inhibitor) (Genbank EU636772). the putative BmCI amino acid sequence presented a 22-residue-signal peptide and 58-residue-mature protein. BmCI amino acid sequence analysis allowed its classification as a Kunitz-BPTI inhibitor with six cysteine residues, a theoretical pI of 7.8, and the presence of Tyr at P1 position in the putative reactive site, suggesting inhibitory activity toward chymotrypsin. in this work, we reported the biochemical characterization of BmCI. the recombinant BmCI expressed in yeast Pichia pastoris was purified by size exclusion and reverse phase chromatographies. rBmCI expression yield was of I mg L-1 of culture. Purified rBmCI confirmed its chymotrypsin inhibitory activity with a low K-i (6.2 pM). the BmCI gene expression analysis by semi-quantitative RT-PCR indicated its transcription in the hemocytes, salivary gland and ovary. the cytotoxic activity of purified rBmCI was demonstrated in BALB/c 3T3 mouse fibroblasts. As assessed by the MTT reduction assay, rBMCI induced a dose-dependent decrease in 3T3 fibroblasts viability (IC50 = 8 mu M). Moreover, flow cytometry analysis revealed that rBmCI is able to induce apoptosis, whereas no effect was observed on cell cycle progression. in conclusion, we demonstrated that rBmCI is cytotoxic against mammalian cells and obtained evidence that this growth inhibition is caused by an apoptosis-inducing activity. (C) 2009 Published by Elsevier B.V.
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Characterization of Brown spider (Loxosceles intermedia) hemolymph: Cellular and biochemical analyses
    (Elsevier B.V., 2015-05-01) Bednaski, A. V.; Trevisan-Silva, D.; Matsubara, F. H.; Boia-Ferreira, M.; Oliverio, M. M.; Gremski, L. H.; Cavalheiro, R. P. [UNIFESP]; De Paula, D. M. B. [UNIFESP]; Paredes-Gamero, E. J. [UNIFESP]; Takahashi, H. K. [UNIFESP]; Toledo, M. S. [UNIFESP]; Nader, H. B. [UNIFESP]; Veiga, S. S.; Chaim, O. M.; Senff-Ribeiro, A.; Universidade Federal do Paraná (UFPR); Univ Fed Parana; Universidade Federal de São Paulo (UNIFESP)
    This is the first study on the hemolymph from a spider of the Loxosceles genus. These animals are responsible for a great number of envenomation cases worldwide. Several studies on Loxosceles venoms have been published, and the knowledge about the venom and its toxins is considerable, not only regarding the biological and biochemical characterization, but also regarding structural, genetic and phylogenetic approaches. However, the literature on Loxosceles hemolymph is nonexistent. the main goal of the present study was to characterize biochemically the hemolymph content, and especially, to identify its different hemocytes. Moreover, many papers have already shown molecules whose source is the hemolymph and their very interesting activities and biomedical applications, for example, antifungal and antibacterial activities. A 2D-SDS-PAGE of brown spider hemolymph showed approximately 111 spots for pH 3-10 and 150 spots for pH 4-7. A lectin-blotting assay showed that hemolymph carbohydrate residues were similar to those found in venom. Several types of TAG and DAG phospholipids were found in the hemolymph and characterized by HPTLC and mass spectrometry. Four different hemocytes were characterized in Loxosceles intermedia hemolymph: prohemocyte, plasmatocyte, granulocyte and adipohemocyte. This paper opens new possibilities on toxinology, studying an unknown biological material, and it characterizes a source of molecules with putative biotechnological applications. (C) 2015 Elsevier B.V. All rights reserved.
  • Imagem de Miniatura
    Item
    Acesso aberto (Open Access)
    The first serine protease inhibitor from Lasiodora sp (Araneae: Theraphosidae) hemocytes
    (Elsevier B.V., 2011-12-01) Soares, Tatiana; Ferreira, Felipe Roberto Borba; Gomes, Francis Soares; Coelho, Luana Cassandra Breitenbach Barroso; Torquato, Ricardo José Soares [UNIFESP]; Napoleão, Thiago Henrique; Cavalcanti, Maria do Socorro de Mendonça; Tanaka, Aparecida Sadae [UNIFESP]; Paiva, Patricia Maria Guedes; Universidade Federal de Pernambuco (UFPE); Universidade Federal de São Paulo (UNIFESP); Univ Pernambuco
    This work reports, for the first time, the purification, characterization and antibacterial activity of an elastase inhibitor from Lasiodora sp. hemocytes (ElLaH). the hemocyte extract inhibited chymotrypsin (22%). trypsin (44%), tissue plasminogen activator (52%), urokinase (58%) and human neutrophil elastase (99%). ElLaH was purified by Trypsin-Sepharose column and RP-HPLC. SDS-PAGE of ElLaH revealed a molecular mass of 8 kDa and MALDI-TOF mass spectrometry revealed a single molecular mass of 8274 Da. the amino terminal sequence determined was LPC(PF)PYQQELTC. the dissociation constant (K) for human neutrophil elastase was 0.32 nM. Hemocyte extract exerted antibacterial effect on Bacillus subtilis and Enterococcus faecalis, while ElLaH was only active against E. faecalis. Currently, Lasiodora sp. is undergoing a systematic review and this study contributes to molecular characterization of the genus. in addition, the results suggest that serine protease inhibitors expressed in Lasiodora sp. hemocytes may be involved in the defense against bacterial infection. (C) 2011 Elsevier B.V. All rights reserved.