title: Enhanced in vitro stimulation of rhesus macaque dendritic cells for activation of SIV-specific T cell responses.
abstract: The macaque-simian immunodeficiency virus (SIV) system is one of the best animal models available to study the role of dendritic cells (DCs) in transmission and pathogenesis of HIV, as well as to test DC-based vaccine and therapeutic strategies. To better define and optimize this system, the responsiveness of macaque monocyte-derived DCs to a variety of maturation stimuli was examined. Characteristic immunophenotypic and functional DC maturation induced by standard monocyte conditioned medium (MCM) was compared to the activation induced by a panel of stimuli including soluble CD40L, LPS, Poly I:C, PGE(2)/TNFalpha, and a cocktail mixture of PGE(2)/TNFalpha/IL-1beta/IL-6. Immunophenotypic analysis confirmed that all stimuli induced stable up-regulation of CD25, CD40, CD80, CD83, CD86, HLA-DR, DC-LAMP (CD208), and DEC-205 (CD205). In general, macaque DCs exhibited weaker responses to LPS and Poly I:C than human DCs, and soluble CD40L stimulation induced variable expression of CD25. Interestingly, while the endocytic capacity of CD40L-matured cells was down-modulated comparably to DCs matured with MCM or the cocktail, the T cell stimulatory activity was not enhanced to the same extent. The particularly reproducible and potent T cell stimulatory capacity of cocktail-treated DCs correlated with a more homogenous mature DC phenotype, consistently high levels of IL-12 production, and better viability upon reculture compared to DCs activated by other stimuli. Furthermore, cocktail-matured DCs efficiently captured and presented inactivated SIV to SIV-primed T cells in vitro. Thus, the cocktail represents a particularly potent and useful stimulus for the generation of efficacious immunostimulatory macaque DCs.
authors.affiliation: Laboratory of Cellular Physiology and Immunology, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
authors.forename: Erin
authors.initials: E
authors.lastname: Mehlhop
authors.forename: Loreley A
authors.initials: LA
authors.lastname: Villamide
authors.forename: Ines
authors.initials: I
authors.lastname: Frank
authors.forename: Agegnehu
authors.initials: A
authors.lastname: Gettie
authors.forename: Christine
authors.initials: C
authors.lastname: Santisteban
authors.forename: Davorka
authors.initials: D
authors.lastname: Messmer
authors.forename: Ralf
authors.initials: R
authors.lastname: Ignatius
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Lifson
authors.forename: Melissa
authors.initials: M
authors.lastname: Pope
mesh_terms: D000818:Animals; D001681:Biological Assay; D003713:Dendritic Cells / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular; D016130:Immunophenotyping; D008253:Macaca mulatta; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology*; D015302:Simian Immunodeficiency Virus / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology