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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

S100A8 acts as an autocrine priming signal for heme-induced human M phi pro-inflammatory responses in hemolytic inflammation

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Autor(es):
Silveira, Angelica A. A. [1] ; Mahon, Olwyn R. [2] ; Cunningham, Clare C. [2] ; Corr, Emma M. [2] ; Mendonca, Rafaela [1] ; Saad, Sara T. O. [1] ; Costa, Fernando F. [1] ; Dunne, Aisling [2] ; Conran, Nicola [1]
Número total de Autores: 9
Afiliação do(s) autor(es):
[1] Univ Estadual Campinas, UNICAMP, Hematol Ctr, Campinas, SP - Brazil
[2] Trinity Coll Dublin, Trinity Biomed Sci Inst, Sch Biochem & Immunol, Dublin - Ireland
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Journal of Leukocyte Biology; v. 106, n. 1, p. 35-43, JUL 2019.
Citações Web of Science: 0
Resumo

Intravascular hemolysis, in addition to reducing red cell counts, incurs extensive vascular inflammation and oxidative stress. One product of hemolysis, heme, is a potent danger associated molecular pattern (DAMP), activating leukocytes and inducing cytokine expression and processing, among other pro-inflammatory effects. We explored pathways by which heme-induced inflammation may be amplified under sterile conditions. Incubation of human M phi s, differentiated from CD14(+) cells, with heme induced time- and concentration-dependent gene and protein expression of S100A8, a myeloid cell-derived alarmin. Human M phi stimulation with recombinant S100A8, in turn, induced robust pro-IL-1 beta expression that was dependent upon NF-kappa B activation, gene transcription, and partially dependent upon TLR4-mediated signaling. Moreover, heme itself stimulated significant M phi pro-IL-1 beta gene and protein expression via an S100A8-mediated mechanism and greatly amplified S100A8-driven NLRP3 inflammasome-mediated IL-1 beta secretion. In vivo, induction of acute intravascular hemolysis in mice induced a rapid elevation of plasma S100A8 that could be abolished by hemopexin, a heme scavenger. Finally, plasma S100A8 levels were found to be significantly elevated in patients with the inherited hemolytic anemia, sickle cell anemia, when compared with levels in healthy individuals. In conclusion, we demonstrate that hemolytic processes are associated with S100A8 generation and that some of the inflammatory effects of heme may be amplified by autocrine S100A8 production. Findings suggest a mechanism by which hemolytic inflammation could be propagated via leukocyte priming by endogenous proteins, even in sterile inflammatory environments such as those that occur in the hemolytic diseases. S100A8 may represent a therapeutic target for reducing inflammation in hemolytic disorders. (AU)

Processo FAPESP: 14/23170-1 - Investigação das propriedades pró-inflamatórias do heme em macrófagos primários humanos
Beneficiário:Angélica Aparecida Antoniellis Silveira
Linha de fomento: Bolsas no Exterior - Estágio de Pesquisa - Doutorado
Processo FAPESP: 14/19173-5 - Inflamação vascular: mecanismos fisiopatológicos de indução e vias de ativação celular
Beneficiário:Nicola Amanda Conran Zorzetto
Linha de fomento: Auxílio à Pesquisa - Regular
Processo FAPESP: 12/22048-2 - Investigação das propriedades pró-inflamatórias do TNF-alfa e do heme em leucócitos in vitro e in vivo
Beneficiário:Angélica Aparecida Antoniellis Silveira
Linha de fomento: Bolsas no Brasil - Doutorado