Increases in IgA+ B cells in the Peyer patches during milk-borne Mouse Mammary Tumor Virus infection are influenced by TLR4 and are completely dependent on the superantigen response.

CABRERA G,; VERCELLI C,; BURZYN D,; BADANO N,; MAGLIOCO A,; COSTA H,; MUNDIÑANO J,; CAMICIA G,; NEPOMNASCHY I,; PIAZZON I

JOURNAL OF GENERAL VIROLOGY

SOC GENERAL MICROBIOLOGY

Año: 2010 vol. 91 p. 2814 - 2820

0022-1317

Mouse mammary tumor virus (MMTV) is a milk-borne betaretrovirus that has developed strategies to exploit and subvert the host immune system. Although mammary glands are the final target of infection, Peyer patches (PP) are the entry site of the virus. Herein, we show that the infection induces increases in the number of PP IgA+ B cells and higher expression of the á circular transcript (CTá), which is a specific marker of the switch to IgA. In addition, IgA+ B cell increases correlated with higher levels of cytokines related to IgA class switching like interleukin-5 and interleukin-6. Of interest, the increases in IgA+ B cells were lower in toll like receptor 4 deficient mice and were completely dependent on the presence of superantigen reactive T cells. Our results point to a new mechanism involved in MMTV infection and suggest that IgA+ B cells may play an important role carrying the virus to the mammary glands.á circular transcript (CTá), which is a specific marker of the switch to IgA. In addition, IgA+ B cell increases correlated with higher levels of cytokines related to IgA class switching like interleukin-5 and interleukin-6. Of interest, the increases in IgA+ B cells were lower in toll like receptor 4 deficient mice and were completely dependent on the presence of superantigen reactive T cells. Our results point to a new mechanism involved in MMTV infection and suggest that IgA+ B cells may play an important role carrying the virus to the mammary glands.