title: [Regulatory T cell depletion increases the number of CD8 cells during mouse mammary tumor virus infection].
abstract: Mouse mammary tumor virus (MMTV) is a milk-borne betaretrovirus that has developed strategies to exploit and subvert the host immune system. We have shown in a natural model of MMTV infection that the virus causes early and progressive increases in superantigen (Sag)-specific CD4+ CD25+ Foxp3+ regulatory T cells (Treg) in Peyer's patches. Herein, we evaluated whether the depletion of Treg cells affects the CD8+ population during milk-borne MMTV infection. At day 6 of infection, the depletion of Treg cells increased the percentage and absolute number of CD8+ cells in lymph nodes as well as the mean intensity fluorescence of the CD44 activation marker. The absolute number of CD8+ cells was increased in cells bearing both Sag reactive and non-reactive TCR Vβ chains. We have previously shown that regulatory T cell depletion at day 6 of infection decrease viral load. Results reported herein suggest that at least after day 6 of MMTV infection Treg cells play an inhibiting role on CD8 antiviral response.
authors: Instituto de Leucemia Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas, División Medicina Experimental, Instituto de Investigaciones Hematológicas, Academia Nacional de Medicina, Buenos Aires, Argentina.
authors: Gabriel
authors: G
authors: Cabrera
authors: Juliana
authors: J
authors: Mundiñano
authors: Gabriela
authors: G
authors: Camicia
authors: Héctor
authors: H
authors: Costa
authors: Irene
authors: I
authors: Nepomnaschy
authors: Isabel
authors: I
authors: Piazzon
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D007111:Immunity, Cellular / Q000502:physiology; D008212:Lymphocyte Depletion; D008325:Mammary Neoplasms, Experimental / Q000276:immunology*; D051379:Mice; D012192:Retroviridae Infections / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D013997:Time Factors; D014412:Tumor Virus Infections / Q000276:immunology*