title: Improving the therapeutic index of CpG oligodeoxynucleotides by intralymphatic administration.
abstract: Signal transduction initiated by TLR such as TLR9, a natural receptor for unmethylated cytosine-guanine-rich motifs (CpG), results in activation of transcription factors, including NF-kappaB, with substantial impact on the innate and adaptive immunity. However, practical application of new adjuvants such as CpG oligodeoxynucleotides (ODN) remains a challenge, since prominent systemic activation of NF-kappaB may result in severe side effects reminiscent of septic shock, thus limiting their therapeutic index (TI). Low-dose administration of CpG ODN into lymph nodes has been evaluated as a means to reduce systemic side effects while retaining strong adjuvant properties. To this aim, a prototype immune-stimulating CpG ODN was used to enhance the antibody production against the antigen phospholipase A(2) and the CD8(+) T cell responses to ovalbumin in mice. When administered subcutaneously, high CpG ODN doses (>10 nmol) were required to enhance antibody and CD8(+) T cell responses. In contrast, when administered directly into a lymph node, much lower amounts of CpG (<0.1 nmol) were sufficient for a similar immune-enhancing effect. Systemic adverse reactions induced by CpG ODN were only detected at higher doses (1-10 nmol), independently of the route of administration. Finally, low-dose CpG ODN, administered in a targeted fashion to HLA-A2.1(+) transgenic mice, greatly elevated anti-tumor CD8(+) T cell immunity. Thus, intralymphatic administration of CpG ODN considerably improves the TI and may greatly enable a safe and effective use in the clinic.
authors.affiliation: University of Zurich, Zurich, Switzerland.
authors.forename: Barbara R
authors.initials: BR
authors.lastname: von Beust
authors.forename: Pål
authors.initials: P
authors.lastname: Johansen
authors.forename: Kent A
authors.initials: KA
authors.lastname: Smith
authors.forename: Adrian
authors.initials: A
authors.lastname: Bot
authors.forename: Tazio
authors.initials: T
authors.lastname: Storni
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Kündig
mesh_terms: D000210:Acute-Phase Reaction; D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D003713:Dendritic Cells / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008198:Lymph Nodes / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009838:Oligodeoxyribonucleotides / Q000008:administration & dosage* / Q000633:toxicity; D013163:Splenomegaly / Q000139:chemically induced; D018417:Th1 Cells / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; C408982:CPG-oligonucleotide; D009838:Oligodeoxyribonucleotides