title: Leishmania (Viannia) braziliensis: human mast cell line activation induced by logarithmic and stationary promastigote derived-lysates.
abstract: Herein we investigate the ability of live promastigotes and total lysate of Leishmania (Viannia) braziliensis, derived from parasites in the logarithmic (L-Lb) or stationary phase (S-Lb), to induce human mast cell line (HMC-1) activation. In comparison with medium-treated cells, a significant histamine release was observed in HMC-1 cultures stimulated with S-Lb. Lipophosphoglycan also induced histamine release by HMC-1 cells. In immunocytochemical assays, we found a marked staining for tryptase in medium-treated HMC-1 cells, however, stimulation with L-Lb or S-Lb caused a marked decrease in the color reaction as well as in the number of tryptase-positive cells. L-Lb and S-Lb induced an evident decrease in the intracellular expression of IL-4 but not IL-12. Live stationary promastigotes were able to induce high levels of IL-4 release in HMC-1 cultures. Furthermore, these cells released significant amounts of IL-12 when incubated with both types of live promastigotes. These results indicate that L. (V.) braziliensis promastigotes differ in their ability to induce direct human mast cells activation, according to the growth phase of the parasite. Furthermore, the release of pro-inflammatory mediators and cytokines could represent an important phenomenon that might favor the initial establishment of the infection.
authors.affiliation: Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Márcia Pereira
authors.initials: MP
authors.lastname: de Oliveira
authors.forename: Marcia Coronha R
authors.initials: MC
authors.lastname: Lima
authors.forename: Andrea S
authors.initials: AS
authors.lastname: Calheiros
authors.forename: Marco A
authors.initials: MA
authors.lastname: Martins
authors.forename: Paulo Renato Z
authors.initials: PR
authors.lastname: Antas
authors.forename: Paula Melo
authors.initials: PM
authors.lastname: De Luca
authors.forename: Claude
authors.initials: C
authors.lastname: Pirmez
mesh_terms: D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000032:analysis / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006636:Histamine Release / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D018664:Interleukin-12 / Q000032:analysis / Q000378:metabolism; D015847:Interleukin-4 / Q000032:analysis / Q000378:metabolism; D007892:Leishmania braziliensis / Q000502:physiology*; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism / Q000469:parasitology*; D051379:Mice; D012697:Serine Endopeptidases / Q000378:metabolism; D053802:Tryptases
chemical_list: D016207:Cytokines; C509190:Tpsb2 protein, mouse; D018664:Interleukin-12; D015847:Interleukin-4; D012697:Serine Endopeptidases; C509222:Tpsab1 protein, mouse; D053802:Tryptases