title: Helminthic infection down-regulates type 1 immune responses in human T cell lymphotropic virus type 1 (HTLV-1) carriers and is more prevalent in HTLV-1 carriers than in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis.
abstract: 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)- gamma 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- gamma -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.
authors.affiliation: Servico de Imunologia do Hospital Unversitario Prof. Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Aurelia F
authors.initials: AF
authors.lastname: Porto
authors.forename: Silvane B
authors.initials: SB
authors.lastname: Santos
authors.forename: André L
authors.initials: AL
authors.lastname: Muniz
authors.forename: Vanessa
authors.initials: V
authors.lastname: Basilio
authors.forename: Waldyr
authors.initials: W
authors.lastname: Rodrigues
authors.forename: Franklin A
authors.initials: FA
authors.lastname: Neva
authors.forename: Walderez O
authors.initials: WO
authors.lastname: Dutra
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Gollob
authors.forename: Steven
authors.initials: S
authors.lastname: Jacobson
authors.forename: Edgar M
authors.initials: EM
authors.lastname: Carvalho
mesh_terms: D000328:Adult; D001938:Brazil; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002353:Carrier State / Q000276:immunology*; D002478:Cells, Cultured; D005260:Female; D015490:HTLV-I Infections / Q000150:complications* / Q000276:immunology*; D006373:Helminthiasis / Q000150:complications* / Q000453:epidemiology / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000032:analysis; D016753:Interleukin-10 / Q000032:analysis; D015848:Interleukin-5 / Q000032:analysis; D008297:Male; D008875:Middle Aged; D015493:Paraparesis, Tropical Spastic / Q000150:complications* / Q000276:immunology; D012555:Schistosomiasis mansoni / Q000150:complications / Q000453:epidemiology / Q000276:immunology; D013322:Strongyloidiasis / Q000150:complications / Q000453:epidemiology / Q000276:immunology; D019562:Viral Load
chemical_list: D015848:Interleukin-5; D016753:Interleukin-10; D007371:Interferon-gamma