Effects of Aedes aegypti salivary components on dendritic cell and lymphocyte biology

0420947 - BC 2014 RIV GB eng J - Článek v odborném periodiku
Bizzarro, B. - Barros, M.S. - Maciel, C. - Gueroni, D.I. - Lino, C.N. - Campopiano, J. - Kotsyfakis, Michalis - Amarante-Mendes, G.P. - Calvo, E. - Capurro, M.L. - Sa-Nunes, A.
Effects of Aedes aegypti salivary components on dendritic cell and lymphocyte biology.
Parasites & Vectors. Roč. 6, NOV 2013 (2013), s. 329. ISSN 1756-3305. E-ISSN 1756-3305
Institucionální podpora: RVO:60077344
Klíčová slova: dendritic cells * T-cells * Aedes aegypti * saliva * apoptosis
Kód oboru RIV: EC - Imunologie
Impakt faktor: 3.251, rok: 2013

Saliva is a key element of interaction between hematophagous mosquitoes and their vertebrate hosts. In addition to allowing a successful blood meal by neutralizing or delaying hemostatic responses, the salivary cocktail is also able to modulate the effector mechanisms of host immune responses facilitating, in turn, the transmission of several types of microorganisms. Understanding how the mosquito uses its salivary components to circumvent host immunity might help to clarify the mechanisms of transmission of such pathogens and disease establishment. Flow cytometry was used to evaluate if increasing concentrations of A. aegypti salivary gland extract (SGE) affects bone marrow-derived DC differentiation and maturation. Lymphocyte proliferation in the presence of SGE was estimated by a colorimetric assay. Western blot and Annexin V staining assays were used to assess apoptosis in these cells. Naive and memory cells from mosquito-bite exposed mice or OVA-immunized mice and their respective controls were analyzed by flow cytometry. Concentration-response curves were employed to evaluate A. aegypti SGE effects on DC and lymphocyte biology. DCs differentiation from bone marrow precursors, their maturation and function were not directly affected by A. aegypti SGE (concentrations ranging from 2.5 to 40 mug/mL). On the other hand, lymphocytes were very sensitive to the salivary components and died in the presence of A. aegypti SGE, even at concentrations as low as 0.1 mug/mL. In addition, A. aegypti SGE was shown to induce apoptosis in all lymphocyte populations evaluated (CD4+ and CD8+ T cells, and B cells) through a mechanism involving caspase-3 and caspase-8, but not Bim. By using different approaches to generate memory cells, we were able to verify that these cells are resistant to SGE effects. Our results show that lymphocytes, and not DCs, are the primary target of A. aegypti salivary components.
Trvalý link: http://hdl.handle.net/11104/0227646