Effect of mosquito midgut trypsin activity on dengue-2 virus infection and dissemination in Aedes aegypti
Autor(es): Molina-Cruz, A; Gupta, L; Richardson, J; Bennett, KF; Black, W; Barillas-Mury, C
Resumo: The effect of mosquito midgut trypsins in dengue serotype 2 flavivirus (DENV-2) infectivity to Aedes aegypti was studied. Addition of soybean trypsin inhibitor (STI) in a DENV-2 infectious blood meal resulted in a 91-97% decrease in midgut DENV-2 RNA copies (qRT-PCR analysis). STI treatment also resulted in slower DENV-2 replica:ion in the midgut, less DENV-2 E protein expression, and decreased dissemination to the thorax and the head. A second uninfected blood meal, 7 days after the STI-treated infectious meal, significantly increased DENV-2 replication in the midgut and recovered oogenesis, suggesting that the lower viral infection caused by STI was in part due to a nutritional effect. Mosquitoes fed DENV-2 digested in vitro with bovine trypsin (before STI addition) exhibited a transient increase in midgut DENV-2 4 days postinfection. Blood digestion and possibly DENV-2 proteolytic processing, mediated by midgut trypsins, influence the rate of DENV-2 infection, replication, and dissemination in Ae. aegypti.
Palavras-Chave: Reverse - Transcription-Pcr; Borne encephalitis - Virus; Yellow fever - Virus; Replicative intermediate; Monoclonal - Antibodies; Vector competence; Bluetongue virus; Oral infection; Blood; Cells
Imprenta: American Journal of Tropical Medicine and Hygiene, v. 72, n. 5, p. 631-637, 2005
Descritores: Aedes aegypti - Biochemistry ; Aedes aegypti - Infectious diseases ; Aedes aegypti - RT-PCR ; Aedes aegypti - Public health
Data de publicação: 2005
