title: Profiles of Th1 and Th2 cytokines after primary and secondary infection by Schistosoma mansoni in the semipermissive rat host.
abstract: In contrast to most mouse strains, rats eliminate the primary schistosome burden around 4 weeks postinfection and subsequently develop protective immunity to reinfection. In rat schistosomiasis, we have shown predominant expression of a Th2-type cytokine response at the mRNA level after primary infection. In the present study, we showed a significant increase in interleukin-4 (IL-4) mRNA expression in inguinal lymph nodes early after a secondary infection. IL-5 mRNA expression showed a significant increase at days 2 and 4 postreinfection in the spleen and lymph nodes, respectively. We did not detect any gamma interferon (IFN-gamma) mRNA after a challenge infection. Analysis of cytokine secretion by stimulated spleen cells after a primary infection showed predominant expression of IL-4 with maximum production on day 21, accompanied by production of IL-5 from day 11 to day 67. A significant increase in IFN-gamma secretion was detected at day 21. Analysis of immunoglobulin G2b (IgG2b) and IgG2c (Th1-related isotypes) showed undetectable levels of IgG2b, but detectable levels of specific IgG2c antibodies were observed from day 42. The analysis of Th2-related isotypes showed high specific IgG1 and IgG2a antibody titers from day 29. After a secondary infection, only IL-4 and IL-5 secretion was sustained. This is supported by the increased production of Th2-related isotypes. These findings showed that S. mansoni infection can drive Th2 responses in rats in the absence of egg production which is required to induce a Th2 response in mice and are in favor of the role of Th2-type cytokines in protective immunity against reinfection.
authors.affiliation: Institut Pasteur de Lille, 59019 Lille Cedex, France. catherine.cetre@pasteur-lille.fr
authors.forename: C
authors.initials: C
authors.lastname: Cêtre
authors.forename: C
authors.initials: C
authors.lastname: Pierrot
authors.forename: C
authors.initials: C
authors.lastname: Cocude
authors.forename: S
authors.initials: S
authors.lastname: Lafitte
authors.forename: A
authors.initials: A
authors.lastname: Capron
authors.forename: M
authors.initials: M
authors.lastname: Capron
authors.forename: J
authors.initials: J
authors.lastname: Khalife
mesh_terms: D000818:Animals; D016207:Cytokines / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D007132:Immunoglobulin Isotypes / Q000145:classification; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015847:Interleukin-4 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015848:Interleukin-5 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007700:Kinetics; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D012550:Schistosoma mansoni / Q000276:immunology; D012555:Schistosomiasis mansoni / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology* / Q000378:metabolism; D018418:Th2 Cells / Q000276:immunology* / Q000378:metabolism
chemical_list: D016207:Cytokines; D007132:Immunoglobulin Isotypes; D015848:Interleukin-5; D015847:Interleukin-4; D007371:Interferon-gamma