Analysis of tumor necrosis factor-alpha serum level in brazilian patients with dengue-2

supporting

confidence: 87%

“…Pro-inflammatory cytokines have been detected in patients from Asia and Central America (Hober et al 1993, Kuno & Bailey 1994 and also in Brazilian patients (Kubelka et al 1995, Pinto et al 1999. The association of cytokine production and severity has been suggested.…”

mentioning

confidence: 99%

Detection of circulant tumor necrosis factor-alpha , soluble tumor necrosis factor p75 and interferon-gamma in Brazilian patients with dengue fever and dengue hemorrhagic fever

Braga

Moura

Pinto

et al. 2001

“…During this work, TNF-a, IL-6, sTNFRp55 and sTNFRp75 were detected in the sera of Brazilian patients with DF, devoid of hemorrhagic manifestations and infected with Dengue-1 or -2. In general, the levels of cytokines in most of our DF patients were lower than those described in literature for DHF/DSS (Hober et al 1993, 1996a, Kuno & Bailey 1994, Iyngkaran et al 1995, Kubelka et al 1995, Bethell et al 1998. This may be explained either by relative disease mildness, virus load, by differences in viral serotype, host genetic factors that may influence in the immunological responses or in test sensitivity.…”

Section: Discussioncontrasting

confidence: 47%

“…Pro-inflammatory cytokines were found to be increased in Asiatic and American patients with DHF/DSS (Hober et al 1993, Kuno & Bailey 1994, Iyngkaran et al 1995, Kubelka et al 1995 and recently soluble TNF receptor was detected in DHF/DSS patients (Hober et al 1996b, Bethell et al 1998. Nevertheless, these investigations are far from elucidating the complex mechanisms of immunopathology during dengue disease; more cases in different countries and several immunological parameters deserve to be studied.…”

mentioning

confidence: 98%

Increased Pro-inflammatory Cytokines (TNF-a and IL-6) and Anti-inflammatory Compounds (sTNFRp55 and sTNFRp75) in Brazilian Patients during Exanthematic Dengue Fever

Pinto¹,

Oliveira²,

Braga³

et al. 1999

Pro-inflammatory cytokines, tumor necrosis factor (TNF-alpha), interleukin-6 (IL-6) and interleukin-1beta (IL-1beta) 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-alpha and IL-6 levels were significantly higher than control subjects in 32% and 52% 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% and 84% patients, respectively. Most patients had IL-1beta levels not different from those of normal subjects, except for one case. Only 16% patients had altered levels of IL-1Ra. 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.

“…TNF-α is a pro-inflammatory cytokine that has often been found in patients with acute dengue fever and high levels are associated with haemorrhagic manifestations (Hober et al 1993, Kubelka et al 1995, Braga et al 2001, Chakravarti & Kumaria 2006. Together with IL-1β, TNF-α is known to increase acute phase protein production and act in synergy with other factors to induce microbicidal activity during phagocytosis (Clark 2007).…”

Section: Discussionmentioning

confidence: 99%

Dengue-2 and yellow fever 17DD viruses infect human dendritic cells, resulting in an induction of activation markers, cytokines and chemokines and secretion of different TNF-α and IFN-α profiles

Gandini

Reis

Torrentes-Carvalho

et al. 2011

Flaviviruses cause severe acute febrile and haemorrhagic infections, including dengue and yellow fever and the pathogenesis of these infections is caused by an exacerbated immune response. Dendritic cells (DCs) are targets for dengue virus (DENV) and yellow fever virus (YF) replication and are the first cell population to interact with these viruses during a natural infection, which leads to an induction of protective immunity in humans. We studied the infectivity of DENV2 (strain 16681), a YF vaccine (YF17DD) and a chimeric YF17D/DENV2 vaccine in monocytederived DCs in vitro with regard to cell maturation, activation and cytokine production. Higher viral antigen positive cell frequencies were observed for DENV2 when compared with both vaccine viruses. Flavivirus-infected cultures exhibited dendritic cell activation and maturation molecules. CD38 expression on DCs was enhanced for both DENV2 and YF17DD, whereas OX40L expression was decreased as compared to mock-stimulated cells, suggesting that a T helper 1 profile is favoured. Tumor necrosis factor (TNF)-α production in cell cultures was significantly higher in DENV2-infected cultures than in cultures infected with YF17DD or YF17D/DENV. In contrast, the vaccines induced higher IFN-α levels than DENV2. The differential cytokine production indicates that DENV2 results in TNF induction, which discriminates it from vaccine viruses that preferentially stimulate interferon expression. These differential response profiles may influence the pathogenic infection outcome.Key words: cytokines -dendritic cells -dengue virus -yellow fever vaccine -flavivirus dendritic cell activation by flavivirus • Mariana Gandini et al.