O papel dos hemócitos na imunidade da aranha Acanthoscurria gomesiana

• Processo: 08/11504-1
• Modalidade de apoio: Auxílio à Pesquisa - Publicações científicas - Artigo
• Data de Início da vigência: 01 de março de 2009
• Data de Término da vigência: 31 de agosto de 2009
• Área do conhecimento: Ciências Biológicas - Imunologia
• Pesquisador responsável: Sirlei Daffre
• Beneficiário: Sirlei Daffre
• Instituição Sede: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brasil
• Assunto(s): Imunologia comparada Imunidade inata
• Palavra(s)-Chave do Pesquisador: antimicrobial peptides | hemocytes | Innate immunity | spider | Imunologia comparada

Resumo

Invertebrates protect themselves against microbial infection through cellular and humoral immune defenses. Since the available information on the immune system of spiders is scarce, the main goal of the present study was to investigate the role of hemocytes and antimicrobial peptides (AMPs) on defense against microbes of spider Acanthoscurria gomesiana. We previously described the purification and characterization of two AMPs from the hemocytes of naïve spider A. gomesiana, gomesin and acanthoscurrin. Here we show that 57% of the hemocytes store both gomesin and acanthoscurrin, either in the same or in different granules. Progomesin labeling in hemocyte granules indicates that gomesin isaddressed to those organelles as a propeptide. In vivo and in vitro experiments showed thatlipopolysaccharide (LPS) and yeast caused the hemocytes to migrate. Once they have reached the infection site, hemocytes may secrete coagulation cascade components and AMPs to cell-free hemolymph.Furthermore, our results suggest that phagocytosis is not the major defense mechanism activated after microbial challenge. Therefore, the main reactions involved in the spider immune defense might be coagulation and AMP secretion. (AU)