The P2X7 receptor antagonist Brilliant Blue G reduces serum human interferon-γ in a humanized mouse model of graft-versus-host disease

N J Geraghty; L Belfiore; D Ly; S R Adhikary; S J Fuller; W Varikatt; M L Sanderson-Smith; V Sluyter; S I Alexander; R Sluyter; D Watson

doi:10.1111/cei.13005

The P2X7 receptor antagonist Brilliant Blue G reduces serum human interferon-γ in a humanized mouse model of graft-versus-host disease

Clin Exp Immunol. 2017 Oct;190(1):79-95. doi: 10.1111/cei.13005. Epub 2017 Jul 24.

Authors

N J Geraghty^{1

2

3}, L Belfiore^{1

2

3}, D Ly^{1

2

3}, S R Adhikary^{1

2

3}, S J Fuller⁴, W Varikatt^{5

6}, M L Sanderson-Smith^{1

2

3}, V Sluyter^{1

2

3}, S I Alexander⁷, R Sluyter^{1

2

3}, D Watson^{1

2

3}

Affiliations

¹ School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia.
² Centre for Medical and Molecular Biosciences, University of Wollongong, Wollongong, NSW, Australia.
³ Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.
⁴ Sydney Medical School Nepean, University of Sydney, Nepean Hospital, Penrith, NSW, Australia.
⁵ Sydney Medical School Westmead, University of Sydney, Westmead Hospital, NSW, Australia.
⁶ Institute for Clinical Pathology and Medical Research, Westmead, NSW Health Pathology, Australia.
⁷ Children's Hospital at Westmead, Westmead, NSW, Australia.

Abstract

Graft-versus-host disease (GVHD) remains a major problem after allogeneic haematopoietic stem cell transplantation, a curative therapy for haematological malignancies. Previous studies have demonstrated a role for the adenosine triphosphate (ATP)-gated P2X7 receptor channel in allogeneic mouse models of GVHD. In this study, injection of human peripheral blood mononuclear cells (PBMCs) into immunodeficient non-obese diabetic-severe combined immunodeficiency-interleukin (NOD-SCID-IL)-2Rγ^null (NSG) mice established a humanized mouse model of GVHD. This model was used to study the effect of P2X7 blockade in this disease. From five weeks post-PBMC injection, humanized mice exhibited clinical signs and histopathology characteristic of GVHD. The P2X7 antagonist, Brilliant Blue G (BBG), blocked ATP-induced cation uptake into both murine and human cells in vitro. Injection of BBG (50 mg/kg) into NSG mice did not affect engraftment of human leucocytes (predominantly T cells), or the clinical score and survival of mice. In contrast, BBG injection reduced circulating human interferon (IFN)-γ significantly, which was produced by human CD4⁺ and CD8⁺ T cells. BBG also reduced human T cell infiltration and apoptosis in target organs of GVHD. In conclusion, the P2X7 antagonist BBG reduced circulating IFN-γ in a humanized mouse model of GVHD supporting a potential role for P2X7 to alter the pathology of this disease in humans.

Keywords: Brilliant Blue G; P2X7 receptor; bone marrow transplantation; graft-versus-host disease; humanized mice; lymphocyte; purinergic signalling.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Apoptosis / drug effects
CD4-Positive T-Lymphocytes / drug effects*
CD4-Positive T-Lymphocytes / immunology
CD8-Positive T-Lymphocytes / drug effects*
CD8-Positive T-Lymphocytes / immunology
Cell Movement / drug effects
Cells, Cultured
Disease Models, Animal
Graft vs Host Disease / drug therapy*
Graft vs Host Disease / immunology
Hematopoietic Stem Cell Transplantation*
Humans
Interferon-gamma / blood*
Interleukin Receptor Common gamma Subunit / genetics
Mice
Mice, Inbred NOD
Mice, Knockout
Mice, SCID
Purinergic P2X Receptor Antagonists / therapeutic use*
Receptors, Purinergic P2X7 / metabolism
Rosaniline Dyes / therapeutic use*
Transplantation, Homologous

Substances

Il2rg protein, mouse
Interleukin Receptor Common gamma Subunit
Purinergic P2X Receptor Antagonists
Receptors, Purinergic P2X7
Rosaniline Dyes
Interferon-gamma
coomassie Brilliant Blue