TLR agonists regulate alloresponses and uncover a critical role for donor APCs in allogeneic bone marrow rejection - PubMed (original) (raw)

. 2008 Oct 15;112(8):3508-16.

doi: 10.1182/blood-2007-09-113670. Epub 2008 Jul 9.

Michael J Ehrhardt, Christopher J Lees, Angela Panoskaltsis-Mortari, Arthur M Krieg, Arlene H Sharpe, William J Murphy, Jonathan S Serody, Hiroaki Hemmi, Shizuo Akira, Robert B Levy, Bruce R Blazar

Affiliations

TLR agonists regulate alloresponses and uncover a critical role for donor APCs in allogeneic bone marrow rejection

Patricia A Taylor et al. Blood. 2008.

Abstract

Cytosine-phosphorothioate-guanine oligodeoxynucleotides (CpG ODNs) are synthetic ODNs with unmethylated DNA sequences that mimic viral and bacterial DNA and protect against infectious agents and tumor challenge. We show that CpG ODNs markedly accelerated graft-versus-host disease (GVHD) lethality by Toll-like receptor 9 (TLR9) ligation of host antigen-presenting cells (APCs), dependent upon host IFNgamma but independent of host IL-12, IL-6, or natural killer (NK) cells. Imaging studies showed significantly more green fluorescent protein-positive (GFP(+)) effector T cells in lymphoid and nonlymphoid organs. In engraftment studies, CpG ODNs promoted allogeneic donor bone marrow (BM) rejection independent of host IFNgamma, IL-12, or IL-6. During the course of these studies, we uncovered a previously unknown and critical role of donor BM APCs in modulating the rejection response. CpG ODNs promoted BM rejection by ligation of donor BM, but not host, TLR9. CpG ODNs did not impair engraftment of TLR9(-/-) BM unless wild-type myeloid (CD11b(+)) but not B-lineage (CD19(+)) BM cells were added to the donor inoculum. The importance of donor BM APCs in modulating the strength of the host antidonor rejection response was underscored by the finding that B7-1/B7-2(-/-) BM was less likely than wild-type BM to be rejected. Collectively, these data offer new insight into the mechanism of alloresponses regulating GVHD and BM rejection.

PubMed Disclaimer

Figures

Figure 1

Figure 1

CpG ODNs accelerate GVHD mortality. (A-C) CpG ODNs were given intraperitoneally to cohorts of mice on d0, d7, d14, d21, and d28 (100 μg/dose). CpG indicates CpG treatment. (A) Lethally irradiated B10.BR mice were given B6 BM and 5 × 106 or 25 × 106 splenocytes (eg, 5S = 5 × 106, 25S = 25 × 106 splenocytes). n = 8/group, P ≤ .036. (B) Lethally irradiated B6 mice were given BALB/c BM and 5 × 106 or 15 × 106 splenocytes. n = 16 to 24 per group, pool of 2 to 3 experiments; P ≤ .009. (C) Nonirradiated, NK cell–depleted BALB/c SCID mice were given 106 or 3 × 106 purified B6 T cells; n = 8/group, P < .05.

Figure 2

Figure 2

CpG ODNs markedly increase GFP+ effector T-cell number in lymphoid and nonlymphoid organs on d14 after BMT. B10.BR mice were lethally irradiated and infused with B6 wild-type BM and B6 GFP+ purified T cells. CpG ODNs (100 μg) was administered on d0 and d7. On d14, mice were killed and indicated organs were imaged. Representative images from 1 of 3 or 4 mice are shown. See “GFP in vivo imaging” for imaging details.

Figure 3

Figure 3

CpG ODNs accelerate GVHD by TLR9 ligation of host but not donor APCs. CpG ODNs were given intraperitoneally to cohorts of mice on d0, d7, d14, d21, and d28 (100 μg/dose). Recipients were lethally irradiated on d−1. (A) B6 TLR9−/− mice were given wild-type BALB/c BM and splenocytes (15 × 106). n = 8 per group, P = .085. (B) Wild-type B6 mice were given BALB/c wild-type BM and BALB/c TLR9−/− splenocytes (15 × 106). n = 8 per group, P = .012. (C) B6 MyD88−/− mice were given wild-type BALB/c BM and splenocytes (5 × 106). n = 7 to 8 per group, P = .432.

Figure 4

Figure 4

CpG ODN–mediated GVHD acceleration is independent of host IL-6, IL-12, and host NK cells, but is dependent on host IFNγ; a TLR7/8 agonist also increased GVHD. CpG ODNs were given intraperitoneally to cohorts of mice on d0, d7, d14, d21, and d28 (100 μg/dose). Recipients were lethally irradiated on d−1. (A) B6 IL-6−/− mice were given BALB/c BM and splenocytes (5 × 106). n = 8 per group, P < .001. (B) B6 IL-12−/− mice were given BALB/c BM and splenocytes (15 × 106). n = 8 per group, P = .003. (C) B6 IFNγ−/− mice were given BALB/c BM and 2 × 106 or 5 × 106 splenocytes. n = 8 per group, P ≥ .273. (D) B6 IFNγ/IL-12−/− mice were given BALB/c BM and splenocytes (5 × 106). n = 6 per group, P = .213. (E,F) NK cell–depleted B6 mice were given BALB/c BM and splenocytes. (E) 5 × 106, P = .041. (F) 2.5 × 106, P = .005; n = 8 per group. (G) B6 mice were given BALB/c BM and splenocytes (5 × 106), and 3M-011 or drug vehicle was given subcutaneously to cohorts of mice every other day for 4 weeks starting d0. n = 10 per group, P = .006. Data were reproduced in a second experiment.

Comment in

References

    1. Ahonen CL, Gibson SJ, Smith RM, et al. Dendritic cell maturation and subsequent enhanced T-cell stimulation induced with the novel synthetic immune response modifier R-848. Cell Immunol. 1999;197:62–72. - PubMed
    1. Ballas ZK, Rasmussen WL, Krieg AM. Induction of NK activity in murine and human cells by CpG motifs in oligodeoxynucleotides and bacterial DNA. J Immunol. 1996;157:1840–1845. - PubMed
    1. Bauer S, Kirschning CJ, Hacker H, et al. Human TLR9 confers responsiveness to bacterial DNA via species-specific CpG motif recognition. Proc Natl Acad Sci U S A. 2001;98:9237–9242. - PMC - PubMed
    1. Gelman AE, Zhang J, Choi Y, Turka LA. Toll-like receptor ligands directly promote activated CD4+ T cell survival. J Immunol. 2004;172:6065–6073. - PMC - PubMed
    1. Hornung V, Rothenfusser S, Britsch S, et al. Quantitative expression of toll-like receptor 1-10 mRNA in cellular subsets of human peripheral blood mononuclear cells and sensitivity to CpG oligodeoxynucleotides. J Immunol. 2002;168:4531–4537. - PubMed

Publication types

MeSH terms

Substances

Grants and funding

LinkOut - more resources