title: Adoptive transfer of CD4(+)Foxp3(+) regulatory T cells to C57BL/6J mice during acute infection with Toxoplasma gondii down modulates the exacerbated Th1 immune response.
abstract: Infection of C57BL/6J mice with the parasite Toxoplasma gondii triggers a powerful Th1 immune response that is detrimental to the host. During acute infection, a reduction in CD4(+)Foxp3(+) regulatory T cells (Treg) has been reported. We studied the role of Treg during T. gondii infection by adoptive transfer of cells purified from transgenic Foxp3(EGFP) mice to infected wild type animals. We found a less severe weight loss, a significant delayed mortality in infected Treg-transferred mice, and reduced pathology of the small intestine that were associated with lower IFN-γ and TNF-α levels. Nevertheless, higher cyst number and parasite load in brain were observed in these mice. Treg-transferred infected mice showed reduced levels of both IFN-γ and TNF-α in sera. A reduced number of CD4(+) T cells producing IFN-γ was detected in these mice, while IL-2 producing CD4(+) T cells were restored to levels nearly similar to uninfected mice. CD25 and CD69 expression of CD4(+) T cells were also down modulated. Our data show that the low Treg cell number are insufficient to modulate the activation of CD4(+) T cells and the production of high levels of IFN-γ. Thus, a delicate balance between an optimal immune response and its modulation by Treg cells must exist.
authors.affiliation: Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico.
authors.forename: Jonadab E
authors.initials: JE
authors.lastname: Olguín
authors.affiliation: Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico.
authors.forename: Jacquelina
authors.initials: J
authors.lastname: Fernández
authors.affiliation: Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico; Unidad de Desarrollo e Investigación en Bioprocesos, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico.
authors.forename: Nohemí
authors.initials: N
authors.lastname: Salinas
authors.affiliation: Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, UNAM, Tlalnepantla, Edo. de México, Mexico.
authors.forename: Imelda
authors.initials: I
authors.lastname: Juárez
authors.affiliation: Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, UNAM, Tlalnepantla, Edo. de México, Mexico.
authors.forename: Miriam
authors.initials: M
authors.lastname: Rodriguez-Sosa
authors.affiliation: Departamento de Patología Experimental, Facultad de Medicina Veterinaria y Zootecnia, UNAM, Mexico City, Mexico.
authors.forename: Jaime
authors.initials: J
authors.lastname: Campuzano
authors.affiliation: Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico.
authors.forename: Carlos
authors.initials: C
authors.lastname: Castellanos
authors.affiliation: Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico. Electronic address: saavedra@unam.mx.
authors.forename: Rafael
authors.initials: R
authors.lastname: Saavedra
mesh_terms: D000208:Acute Disease; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D015536:Down-Regulation / Q000276:immunology; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018417:Th1 Cells / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D007376:Interleukin-2; D007371:Interferon-gamma
keywords: Adoptive transfer; Interferon-gamma; Regulatory T-cells; T(h)1 cells; Toxoplasma gondii