Modulation of murine cellular immune responses and cytokine production by sand fly saliva

摘要: Sand flies (Diptera: Phlebotominae) are hematophagous arthropods and important vectors of Leishmania parasites. During blood feeding, both vector saliva parasites injected by an infected sand fly. The aim this study was to characterize how fly interferes with host immunity in order clarify the mechanism underlying enhancing effect on infection. Spleen cells from naive BALB/c mice were incubated vitro Phlebotomus papatasi, P. sergenti or Lutzomyia longipalpis salivary gland lysate (SGL). We studied cell proliferation cytokine production non-stimulated concanavalin A-stimulated splenocytes. Both spontaneous mitogen-stimulated lymphocyte significantly suppressed SGLs all three species doses tested (equivalent 1/16, 1/4 1 per well). index (a lysate-treated/lysate-untreated ratio) lower when SGL ranging between 0.52 0.30 for splenocytes 0.69–0.32 lymphocytes. This result indicates that different is able suppress proliferative response even potent Leishmania-unrelated mitogen. In parallel experiments, we analysed (1 well) production. levels Th1 (IL-2, IFN-γ) Th2 (IL-4) cytokines determined culture supernatants capture ELISA. Exposure alone did not affect IL-2 IL-4. IFN-γ inhibited papatasi SGL, whereas other two ineffective. modulated; level enhanced species. IL-4 only L. SGL; no changes noted after incubation saliva. species-specific immunomodulation agreement our previous finding composition varies among Taken together, modulate as well These findings further increase understanding fly–host immune relationship.