Expansion of intracellular IFN-γ positive lymphocytes during Mycoplasma agalactiae infection in sheep

• Published in: Research in veterinary science 2011-12, Vol.91 (3), p.e64-e67
• Main Authors: La Manna, M.P., Agnone, A., Villari, S., Puleio, R., Vitale, M., Nicholas, R., Sireci, G., Dieli, F., Loria, G.R.
• Format: Article
• Language: English
• Subjects: Agalactia; Animals; Antibodies, Bacterial - blood; Antibody Specificity; Antigens, Bacterial; CD4 + cells; CD8 + cells; Immunoglobulin G; Interferon-gamma - genetics; Interferon-gamma - metabolism; Leukocytes, Mononuclear - metabolism; Lymphocytes - metabolism; Mastitis; Mycoplasma agalactiae; Mycoplasma Infections - immunology; Mycoplasma Infections - microbiology; Mycoplasma Infections - veterinary; Peripheral blood mononuclear cells; Sheep; Sheep Diseases - microbiology; T cells
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2011.01.029

A method to assess the expansion of antigen-specific intracellular IFN-γ positive T cell subsets during the infection will be helpful for a better understanding of mycoplasmal infections physiopathology in the sheep. We analysed the percentage of antigen-specific lymphocytes positive for intracellular IFN-γ during the infection of sheep with Mycoplasma agalactiae by culturing peripheral blood mononuclear cells of infected or uninfected animals with irradiated M. agalactiae. The expansion of antigen-specific IFN-γ positive lymphocytes in infected sheep was initially sustained by CD4 + T cells at day 15 after infection, when antigen specific IgG start to be detectable, followed by CD8/IFN-γ double positive cells. γδ T-cells were not expanded at any time point analysed. IFNγ + T cells disappear 60 days after infection, suggesting that antigen specific IFNγ + T cells, mainly detected in the early phase of the disease, could be useful to understand the role of cell-mediated immunity during M. agalactiae infection.