Sensitized Lymphocytes and CD40 Ligation Augment Interleukin‐12 Production by Human Dendritic Cells in Response toToxoplasma gondii

1 February 1999

journal article
Published by Oxford University Press (OUP) in The Journal of Infectious Diseases

Vol. 179 (2) , 467-474
https://doi.org/10.1086/314601

Abstract

Dendritic cells (DC) are potent antigen-presenting cells that can stimulate T cell responses by secreting cytokines. During Toxoplasma gondii infection, host immunity is mediated by interferon-gamma, which is induced by interleukin-12 (IL-12). Whether T. gondii infection would stimulate human DC to produce IL-12 was determined. DC were generated from human peripheral blood mononuclear cells cultured with recombinant human granulocyte-macrophage colony-stimulating factor and recombinant human IL-4. DC secreted high levels of IL-12 in response to lipopolysaccharide but not to either live T. gondii tachyzoites or soluble antigen. However, IL-12 production in response to T. gondii was observed when DC were cocultured in contact with lymphocytes isolated from seropositive donors. Ligation of CD40:CD154 was partially essential for IL-12 secretion. These data demonstrate that signals obtained from contact with sensitized lymphocytes are critical for human DC to secrete IL-12 in response to T. gondii.

Keywords

This publication has 0 references indexed in Scilit: