Polymyxin B enhances ISS-mediated immune responses across multiple species.
The immunostimulatory effects of bacterial DNA on mammalian cells have been localized to unmethylated CpG motifs, and synthetic CpG-containing oligodeoxynucleotides that mimic these effects are known as immunostimulatory sequences (ISS). We have found that the polycationic antibiotic, polymyxin B (PMXB), associates with ISS and serum albumin in vitro and forms microparticles that greatly increase the activity of ISS on plasmacytoid dendritic cells (PDCs). Specifically, ISS/PMXB greatly enhanced IFN-alpha production from PDCs and other activities downstream of IFN-alpha, including IFN-gamma secretion, NK lytic activity, and the expression of genes dependent upon IFN-alpha/IFN-gamma. This amplification was specific for the IFN-alpha pathway since other ISS activities, including B cell proliferation, B cell IL-6 secretion, and PDC maturation, were not affected by PMXB. Both the polycationic peptide and lipophilic fatty acid side chain domains of PMXB, as well as the presence of a third party stabilizing agent such as albumin or Tween 85, were required for particle formation and enhanced ISS activity. The ISS-enhancing activity of PMXB was observed across multiple species (human, primate, and mouse) and in vivo (primate, mouse). These data illustrate the usefulness of formulating ISS with a cationic lipopeptide such as PMXB, which focuses and greatly amplifies the ISS-induced pathway of IFN-alpha-mediated responses.
Dynavax Technologies Corporation, Berkeley, CA, USA. jmarshall@dvax.com
Jason D
JD
Marshall
Debbie
D
Higgins
Christi
C
Abbate
Priscilla
P
Yee
Glen
G
Teshima
Gary
G
Ott
Tracy
T
dela Cruz
David
D
Passmore
Karen L
KL
Fearon
Stephen
S
Tuck
Gary
G
Van Nest
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018899:CpG Islands / Q000187:drug effects / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006514:Hepatitis B Surface Antigens / Q000096:biosynthesis / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000276:immunology; D016898:Interferon-alpha / Q000096:biosynthesis / Q000276:immunology; D007371:Interferon-gamma / Q000378:metabolism; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009838:Oligodeoxyribonucleotides / Q000276:immunology / Q000494:pharmacology*; D010215:Papio; D011112:Polymyxin B / Q000494:pharmacology*; D012709:Serum Albumin / Q000276:immunology; D018709:Statistics, Nonparametric
D000900:Anti-Bacterial Agents; D006514:Hepatitis B Surface Antigens; D007074:Immunoglobulin G; D016898:Interferon-alpha; D009838:Oligodeoxyribonucleotides; D012709:Serum Albumin; D007371:Interferon-gamma; D011112:Polymyxin B