Data/hora: 08/06/2024 11:58:00

Provedor de dados: | 56
País: | Brazil
Título: | Increased production of tumor necrosis factor-alpha in whole blood cultures from children with primary malnutrition
Autores: | Azevedo,Z.M.A.; Luz,R.A.; Victal,S.H.; Kurdian,B.; Fonseca,V.M.; Fitting,C.; Câmara,F.P.; Haeffner-Cavaillon,N.; Cavaillon,J.-M.; Gaspar Elsas,M.I.C.; Xavier Elsas,P.
Data: | 2005-02-01
Ano: | 2005
Palavras-chave: | TNF-alpha; Malnutrition; LPS.
Resumo: | Because low tumor necrosis factor-alpha (TNF-alpha) production has been reported in malnourished children, in contrast with high production of TNF-alpha in experimental protein-energy malnutrition, we reevaluated the production of TNF-alpha in whole blood cultures from children with primary malnutrition free from infection, and in healthy sex- and age-matched controls. Mononuclear cells in blood diluted 1:5 in endotoxin-free medium released TNF-alpha for 24 h. Spontaneously released TNF-alpha levels (mean ± SEM), as measured by enzyme immunoassay in the supernatants of unstimulated 24-h cultures, were 10,941 ± 2,591 pg/ml in children with malnutrition (N = 11) and 533 ± 267 pg/ml in controls (N = 18) (P &lt; 0.0001). TNF-alpha production was increased by stimulation with lipopolysaccharide (LPS), with maximal production of 67,341 ± 16,580 pg/ml TNF-alpha in malnourished children and 25,198 ± 2,493 pg/ml in controls (P = 0.002). In control subjects, LPS dose-dependently induced TNF-alpha production, with maximal responses obtained at 2000 ng/ml. In contrast, malnourished patients produced significantly more TNF-alpha with 0.02-200 ng/ml LPS, responded maximally at a 10-fold lower LPS concentration (200 ng/ml), and presented high-dose inhibition at 2000 ng/ml. TNF-alpha production a) was significantly influenced by LPS concentration in control subjects, but not in malnourished children, who responded strongly to very low LPS concentrations, and b) presented a significant, negative correlation (r = -0.703, P = 0.023) between spontaneous release and the LPS concentration that elicited maximal responses in malnourished patients. These findings indicate that malnourished children are not deficient in TNF-alpha production, and suggest that their cells are primed for increased TNF-alpha production.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2005000200005
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2005000200005
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.38 n.2 2005
Fonte: | info:eu-repo/semantics/openAccess