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Texto completo: acesso restrito. p. 612-618. Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2013-11-29T11:17:26Z No. of bitstreams: 1 Silvane B. Santos.pdf: 435684 bytes, checksum: 61d491af11b14d5ca3b7008acbc433af (MD5) Approved for entry into archive by Flávia Ferreira (flaviaccf@yahoo.com.br) on 2014-01-07T13:33:33Z (GMT) No. of bitstreams: 1 Silvane B. Santos.pdf: 435684 bytes, checksum: 61d491af11b14d5ca3b7008acbc433af (MD5) Made available in DSpace on 2014-01-07T13:33:33Z (GMT). No. of bitstreams: 1 Silvane B. Santos.pdf: 435684 bytes, checksum: 61d491af11b14d5ca3b7008acbc433af (MD5) Previous issue date: 2005 Human T cell lymphotropic virus type 1 (HTLV-1) infection is associated with an exacerbated type 1 immune response and secretion of high levels of proinflammatory cytokines. In contrast, helminthic infection induces a type 2 immune response. In the present study, the cytokine profile in HTLV-1 carriers coinfected with helminths (Strongyloides stercoralis and/or Schistosoma mansoni) was compared with that in HTLV-1 carriers not coinfected with helminths. Levels of interferon (IFN)-γ were higher in HTLV-1 carriers not coinfected with helminths than in HTLV-1 carriers coinfected with helminths (P < .05). The overall frequency of IFN-γ-expressing CD8+ and CD4+ cells was decreased in HTLV-1 carriers coinfected with helminths (P > .05). The percentage of interleukin (IL)-5- and IL-10-expressing T cells in HTLV-1 carriers coinfected with helminths was higher than that in HTLV-1 carriers not coinfected with helminths (P < .05). Moreover, we found that the prevalence of helminthic infection was 7-fold higher in HTLV-1 carriers than in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (P < .05). These data show that helminthic infection decreases activation of type 1 cells, which may influence the clinical outcome of HTLV-1 infection.

Texto completo: acesso restrito. p. 612-618. Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2013-11-29T11:17:26Z No. of bitstreams: 1 Silvane B. Santos.pdf: 435684 bytes, checksum: 61d491af11b14d5ca3b7008acbc433af (MD5) Approved for entry into archive by Flávia Ferreira (flaviaccf@yahoo.com.br) on 2014-01-07T13:33:33Z (GMT) No. of bitstreams: 1 Silvane B. Santos.pdf: 435684 bytes, checksum: 61d491af11b14d5ca3b7008acbc433af (MD5) Made available in DSpace on 2014-01-07T13:33:33Z (GMT). No. of bitstreams: 1 Silvane B. Santos.pdf: 435684 bytes, checksum: 61d491af11b14d5ca3b7008acbc433af (MD5) Previous issue date: 2005 Human T cell lymphotropic virus type 1 (HTLV-1) infection is associated with an exacerbated type 1 immune response and secretion of high levels of proinflammatory cytokines. In contrast, helminthic infection induces a type 2 immune response. In the present study, the cytokine profile in HTLV-1 carriers coinfected with helminths (Strongyloides stercoralis and/or Schistosoma mansoni) was compared with that in HTLV-1 carriers not coinfected with helminths. Levels of interferon (IFN)-γ were higher in HTLV-1 carriers not coinfected with helminths than in HTLV-1 carriers coinfected with helminths (P < .05). The overall frequency of IFN-γ-expressing CD8+ and CD4+ cells was decreased in HTLV-1 carriers coinfected with helminths (P > .05). The percentage of interleukin (IL)-5- and IL-10-expressing T cells in HTLV-1 carriers coinfected with helminths was higher than that in HTLV-1 carriers not coinfected with helminths (P < .05). Moreover, we found that the prevalence of helminthic infection was 7-fold higher in HTLV-1 carriers than in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (P < .05). These data show that helminthic infection decreases activation of type 1 cells, which may influence the clinical outcome of HTLV-1 infection.

p. 424-429 Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-11-13T13:29:28Z No. of bitstreams: 1 CONFIG~1....1365-2249.2004.02508.x-1.pdf: 66846 bytes, checksum: 5cf8fbf30ecb0b9ad00d4867363bc580 (MD5) Made available in DSpace on 2012-11-13T13:29:28Z (GMT). No. of bitstreams: 1 CONFIG~1....1365-2249.2004.02508.x-1.pdf: 66846 bytes, checksum: 5cf8fbf30ecb0b9ad00d4867363bc580 (MD5) Previous issue date: 2004 The immunological response in HTLV-1 infected individuals is characterized by a prominent Type-1 cytokine response with high production of IFNg and TNFa. In contrast, helminthic infections and in particular chronic schistosomiasis are associated with a predominant production of IL-4, IL-5, IL-10 and IL-13. Liver fibrosis is the main pathological finding in schistosomiasis that occurs after many years of infection. This pathology is T cell dependent but the immune response mechanisms are not completely understood. The North-east region of Brazil is endemic for both HTLV-1 and schistosomiasis. In the present study the immune response, clinical severity, and therapeutic response to praziquantel of patients with schistosomiasis coinfected with HTLV-1 were compared with patients infected only with S. mansoni. Patients with HTLV-1 and S.mansoni had lower levels of IL-5 (P

Texto completo: acesso restrito. p. 428-432 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2013-12-16T14:59:55Z No. of bitstreams: 1 Edgar M. Carvalho.pdf: 132563 bytes, checksum: 093954a61028123c3187eec11c838ab7 (MD5) Approved for entry into archive by Flávia Ferreira (flaviaccf@yahoo.com.br) on 2014-01-07T13:22:59Z (GMT) No. of bitstreams: 1 Edgar M. Carvalho.pdf: 132563 bytes, checksum: 093954a61028123c3187eec11c838ab7 (MD5) Made available in DSpace on 2014-01-07T13:22:59Z (GMT). No. of bitstreams: 1 Edgar M. Carvalho.pdf: 132563 bytes, checksum: 093954a61028123c3187eec11c838ab7 (MD5) Previous issue date: 2003 The present study was conducted to determine whether interferon (IFN)-γ production by CD4+ cells in patients infected with human T cell lymphotropic virus (HTLV) is associated with expression of Tax, an HTLV type 1 (HTLV-1) transactivator. The frequency of IFN-γ production from CD4+ cells was greater in HTLV-1-infected patients (n = 21) than in uninfected (n = 3) and Strongyloides stercoralis-infected patients (n = 4), and greater in patients with HTLV-1 with detectable Tax than in patients with HTLV-1 with undetectable Tax. In the patients with HTLV-1 with detectable Tax, the majority of CD4+ cells making IFN-γ did not express Tax.

Texto completo: acesso restrito. p. 503–507 Submitted by Suelen Reis (suelen_suzane@hotmail.com) on 2012-12-19T17:29:27Z No. of bitstreams: 1 j.1365-3024.2001.00407.pdf: 95167 bytes, checksum: 5466c786d6eeb307e0761d660b77ce00 (MD5) Made available in DSpace on 2012-12-19T17:29:27Z (GMT). No. of bitstreams: 1 j.1365-3024.2001.00407.pdf: 95167 bytes, checksum: 5466c786d6eeb307e0761d660b77ce00 (MD5) Previous issue date: 2001 Eosinophils, immunoglobilin (Ig)E and cytokines have important roles in defence mechanisms against helminths. In this study, the influence of HTLV-1 infection, characterized by a Th1 type of immune response, was evaluated on the cytokine pattern and parasitic specific IgE response in patients with strongyloidiasis. Patients were divided into four groups: strongyloidiasis without HTLV-1 infection, strongyloidiasis with HTLV-1, HTLV-1 without strongyloidiasis and controls without either helminth infection or HTLV-1. The cytokine profile was determined in supernatants of mononuclear cells stimulated with Strongyloides stercoralis crude antigen and the parasite specific IgE was measured by ELISA. Patients coinfected with HTLV-1 had higher levels of interfron (IFN)-γ and interleukin (IL)-10 (P < 0·05) and lower levels of IL-5 and IgE (P < 0·05) than patients with strongyloidiasis without HTLV-1. There was an inverse relationship between IFN-γ and IL-5 (P = 0·01; rs = − 0·37) and between IFN-γ and parasite specific IgE (P = 0·01; rs = − 0·39), and a direct relationship between IFN-γ and IL-10 (P = 0·04; rs = 0·35). These data show that coinfection with HTLV-1 decreases IL-5 and IgE responses in patients with strongyloidiasis consistent with a relative switch from Th2 to Th1 response. Immunological responses such as these are important in the control of this helminthic infection.

p. 1-6 Submitted by Ana Valéria de Jesus Moura (anavaleria_131@hotmail.com) on 2011-12-13T15:48:37Z No. of bitstreams: 1 Cytokine Profile.pdf: 138406 bytes, checksum: 05a3ef2c66c9aa609e62c6a8393b1a38 (MD5) Made available in DSpace on 2011-12-13T15:48:38Z (GMT). No. of bitstreams: 1 Cytokine Profile.pdf: 138406 bytes, checksum: 05a3ef2c66c9aa609e62c6a8393b1a38 (MD5) Previous issue date: 2001 The modulation of the immune response has been used as therapy for clinical disorders associated with human T-lymphotropic virus type 1 (HTLV-1) infection. In this study, the cytokine profile was evaluated in 26 asymptomatic HTLV-1 blood donors. Additionally, both the cell responsible for producing interferon-γ (IFN-γ) and the role of exogenous interleukin (IL)-10 in downregulating IFN-γ production were studied. Cytokine levels were determined in supernatants of unstimulated lymphocyte cultures by enzyme-linked immunosorbent assay. The levels of IFN-γ, tumor necrosis factor-α, IL-5, and IL-10 were higher in supernatants of the lymphocyte cultures taken from HTLV-1-infected donors than in those taken from healthy subjects. Although depletion of CD8+ T cells and natural killer cells did not affect IFN-γ production, depletion of CD4+ T cells significantly decreased IFN-γ production. Furthermore, at a concentration of 2 ng/ml, IL-10 had only a minimum effect on IFN-γ producti on, although at high concentrations (100 ng/ml), IL-10 decreased IFN-γ production by 50% in HTLV-1-infected individuals. These data indicate that both T helper 1 and T helper 2 cytokines are elevated in HTLV-1 infection and that IL-10 in high concentrations modulates IFN-γ production in these patients.