Increased pro-inflammatory cytokines (TNF-[alfa] and IL-6) and anti-inflammatory compounds (sTNFRp55 and sTNFRp75) in brazilian patients during exanthematic dengue fever

RESUMO

Pro-inflammatory cytokines, tumor necrosis factor (TNF-[alfa]), interleukin-6(IL-6) and interleukin-1ß (IL-1ß) as well as anti-inflammatory compounds, soluble TNF-Receptor p55 (sTNFRp55), sTNFRp75 and IL-1 receptor antagonist (sIL-1Ra), were investigated in 34 Brazilian cases of dengue fever (DF) originated from a study of exanthematic virosis. The presence of pro-inflammatory cytokines was detected in sera from these patients by ELISA. TNF-[alfa] and IL-6 levels were significantly higher than control subjects in 32 (por cento) and 52(por cento) patients, respectively. To our knowledge this was the first time a receptor antagonist and soluble receptors for cytokines were detected in sera obtained during exanthematic DF without hemorrhagic manifestations. Both sTNFRp55 and sTNFRp75 were consistently elevated in 42 (por cento) and 84 (por cento) patients, respectively. Most patients had IL-1ß levels not different from those of normal subjects, except for one case. Only 16 (por cento) patients had altered levels of IL-Ra. Previous studies in dengue hemorrhagic fever patients demonstrated production of these soluble factors; here we observed that they are found in absence of hemorrhagic manifestations. The possible role of these anti-inflammatory compounds in immune cell activation and in regulating cytokine-mediated pathogenesis during dengue infection is discussed.