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Sligar C, Reilly E, Cuthbertson P, Vine KL, Bird KM, Elhage A, Alexander SI, Sluyter R, Watson D. Graft-versus-leukaemia immunity is retained following treatment with post-transplant cyclophosphamide alone or combined with tocilizumab in humanised mice. Clin Transl Immunology 2024; 13:e1497. [PMID: 38495918 PMCID: PMC10941522 DOI: 10.1002/cti2.1497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/06/2024] [Accepted: 03/01/2024] [Indexed: 03/19/2024] Open
Abstract
Objectives Donor haematopoietic stem cell transplantation treats leukaemia by inducing graft-versus-leukaemia (GVL) immunity. However, this benefit is often mitigated by graft-versus-host disease (GVHD), which is reduced by post-transplant cyclophosphamide (PTCy) alone or combined with tocilizumab (TOC) in humanised mice. This study established a preclinical humanised mouse model of GVL and investigated whether PTCy alone or combined with TOC impacts GVL immunity. Methods NOD-scid-IL2Rγnull mice were injected with 2 × 107 human peripheral blood mononuclear cells (hPBMCs) on day 0 and with 1 × 106 THP-1 acute myeloid leukaemia cells on day 14. In subsequent experiments, mice were also injected with PTCy (33 mg kg-1) or Dulbecco's phosphate buffered saline (PBS) on days 3 and 4, alone or combined with TOC or control antibody (25 mg kg-1) twice weekly for 28 days. Clinical signs of disease were monitored until day 42. Results Mice with hPBMCs from three different donors and THP-1 cells showed similar survival, clinical score and weight loss. hCD33+ leukaemia cells were minimal in mice reconstituted with hPBMCs from two donors but present in mice with hPBMCs from a third donor, suggesting donor-specific GVL responses. hPBMC-injected mice treated with PTCy alone or combined with TOC (PTCy + TOC) demonstrated prolonged survival compared to control mice. PTCy alone and PTCy + TOC-treated mice with hPBMCs showed minimal hepatic hCD33+ leukaemia cells, indicating sustained GVL immunity. Further, the combination of PTCy + TOC reduced histological damage in the lung and liver. Conclusion Collectively, this research demonstrates that PTCy alone or combined with TOC impairs GVHD without compromising GVL immunity.
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Affiliation(s)
- Chloe Sligar
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | - Ellie Reilly
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | - Peter Cuthbertson
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | - Kara L Vine
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | - Katrina M Bird
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | - Amal Elhage
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | | | - Ronald Sluyter
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
| | - Debbie Watson
- Molecular Horizons and School of Chemistry and Molecular BioscienceUniversity of WollongongWollongongNSWAustralia
- Illawarra Health and Medical Research InstituteWollongongNSWAustralia
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Cuthbertson P, Button A, Sligar C, Elhage A, Vine KL, Watson D, Sluyter R. Post-Transplant Cyclophosphamide Combined with Brilliant Blue G Reduces Graft-versus-Host Disease without Compromising Graft-versus-Leukaemia Immunity in Humanised Mice. Int J Mol Sci 2024; 25:1775. [PMID: 38339054 PMCID: PMC10855770 DOI: 10.3390/ijms25031775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/22/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024] Open
Abstract
Allogeneic haematopoietic stem cell transplantation (HSCT) leads to the establishment of graft-versus-leukaemia (GVL) immunity, but in many cases also results in the development of graft-versus-host disease (GVHD). This study aimed to determine if P2X7 antagonism using Brilliant Blue G (BBG) could improve the beneficial effects of post-transplant cyclophosphamide (PTCy) in a humanised mouse model of GVHD, without comprising GVL immunity. NOD.Cg-Prkdcscid Il2rgtm1Wjl (NSG) mice were injected with human peripheral blood mononuclear cells (PBMCs) (Day 0), then with cyclophosphamide (33 mg/kg) on Days 3 and 4, and with BBG (50 mg/kg) (or saline) on Days 0-10. PTCy with BBG reduced clinical GVHD development like that of PTCy alone. However, histological analysis revealed that the combined treatment reduced liver GVHD to a greater extent than PTCy alone. Flow cytometric analyses revealed that this reduction in liver GVHD by PTCy with BBG corresponded to an increase in human splenic CD39+ Tregs and a decrease in human serum interferon-γ concentrations. In additional experiments, humanised NSG mice, following combined treatment, were injected with human THP-1 acute myeloid leukaemia cells on Day 14. Flow cytometric analyses of liver CD33+ THP-1 cells showed that PTCy with BBG did not mitigate GVL immunity. In summary, PTCy combined with BBG can reduce GVHD without compromising GVL immunity. Future studies investigating P2X7 antagonism in combination with PTCy may lead to the development of novel treatments that more effectively reduce GVHD in allogeneic HSCT patients without promoting leukaemia relapse.
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Affiliation(s)
- Peter Cuthbertson
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Amy Button
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Chloe Sligar
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Amal Elhage
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Kara L. Vine
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Debbie Watson
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Ronald Sluyter
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (P.C.); (A.B.); (C.S.); (A.E.); (K.L.V.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
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Elhage A, Cuthbertson P, Sligar C, Watson D, Sluyter R. A Species-Specific Anti-Human P2X7 Monoclonal Antibody Reduces Graft-versus-Host Disease in Humanised Mice. Pharmaceutics 2023; 15:2263. [PMID: 37765233 PMCID: PMC10536354 DOI: 10.3390/pharmaceutics15092263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/26/2023] [Accepted: 08/27/2023] [Indexed: 09/29/2023] Open
Abstract
Graft-versus-host disease (GVHD) is a T cell-mediated inflammatory disorder that arises from allogeneic haematopoietic stem cell transplantation and is often fatal. The P2X7 receptor is an extracellular adenosine 5'-triphosphate-gated cation channel expressed on immune cells. Blockade of this receptor with small molecule inhibitors impairs GVHD in a humanised mouse model. A species-specific blocking monoclonal antibody (mAb) (clone L4) for human P2X7 is available, affording the opportunity to determine whether donor (human) P2X7 contributes to the development of GVHD in humanised mice. Using flow cytometric assays of human RPMI 8266 and murine J774 cells, this study confirmed that this mAb bound and impaired human P2X7. Furthermore, this mAb prevented the loss of human regulatory T cells (hTregs) and natural killer (hNK) T cells in vitro. NOD-scid IL2Rγnull mice were injected with 10 × 106 human peripheral blood mononuclear cells (Day 0) and an anti-hP2X7 or control mAb (100 μg i.p. per mouse, Days 0, 2, 4, 6, and 8). The anti-hP2X7 mAb increased hTregs and hNK cells at Day 21. Moreover, anti-hP2X7 mAb-treatment reduced clinical and histological GVHD in the liver and lung compared to the control treatment at disease endpoint. hTregs, hNK, and hNK T cell proportions were increased, and human T helper 17 cell proportions were decreased at endpoint. These studies indicate that blockade of human (donor) P2X7 reduces GVHD development in humanised mice, providing the first direct evidence of a role for donor P2X7 in GVHD.
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Affiliation(s)
- Amal Elhage
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (A.E.); (P.C.); (C.S.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Peter Cuthbertson
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (A.E.); (P.C.); (C.S.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Chloe Sligar
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (A.E.); (P.C.); (C.S.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Debbie Watson
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (A.E.); (P.C.); (C.S.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Ronald Sluyter
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia; (A.E.); (P.C.); (C.S.); (D.W.)
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
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Sligar C, Cuthbertson P, Miles NA, Adhikary SR, Elhage A, Zhang G, Alexander SI, Sluyter R, Watson D. Tocilizumab increases regulatory T cells, reduces natural killer cells and delays graft-versus-host disease development in humanized mice treated with post-transplant cyclophosphamide. Immunol Cell Biol 2023. [PMID: 37191045 DOI: 10.1111/imcb.12652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/02/2023] [Accepted: 04/19/2023] [Indexed: 05/17/2023]
Abstract
Graft-versus-host disease (GVHD) is a life-threatening complication following donor hematopoietic stem cell transplantation, where donor T cells damage host tissues. This study investigated the effect of tocilizumab (TOC) combined with post-transplant cyclophosphamide (PTCy) on immune cell engraftment and GVHD development in a humanized mouse model. NOD-scid-IL2Rγnull (NSG) mice were injected intraperitoneally with 2 × 107 human (h) peripheral blood mononuclear cells and cyclophosphamide (33 mg kg-1 ) or saline on days 3 and 4, then TOC or control antibody (0.5 mg mouse-1 ) twice weekly for 28 days. Mice were monitored for clinical signs of GVHD for either 28 or 70 days. Spleens and livers were assessed for human leukocyte subsets, and serum cytokines and tissue histology were analyzed. In the short-term model (day 28), liver and lung damage were reduced in PTCy + TOC compared with control mice. All groups showed similar splenic hCD45+ leukocyte engraftment (55-60%); however, PTCy + TOC mice demonstrated significantly increased (1.5-2-fold) splenic regulatory T cells. Serum human interferon gamma was significantly reduced in PTCy + TOC compared with control mice. Long-term (day 70), prolonged survival was similar in PTCy + TOC (median survival time, > 70 days) and PTCy mice (median survival time, 56 days). GVHD onset was significantly delayed in PTCy + TOC, compared with TOC or control mice. Notably, natural killer cells were reduced (77.5%) in TOC and PTCy + TOC mice. Overall, combining PTCy with TOC increases regulatory T cells and reduces clinical signs of early GVHD, but does not improve long-term survival compared with PTCy alone.
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Affiliation(s)
- Chloe Sligar
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Peter Cuthbertson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Nicole A Miles
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Sam R Adhikary
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Amal Elhage
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Geoff Zhang
- The Centre for Kidney Research, The Children's Hospital at Westmead, NSW, Westmead, Australia
| | - Stephen I Alexander
- The Centre for Kidney Research, The Children's Hospital at Westmead, NSW, Westmead, Australia
| | - Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Debbie Watson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
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Sluyter R, Cuthbertson P, Elhage A, Sligar C, Watson D. Purinergic signalling in graft-versus-host disease. Curr Opin Pharmacol 2023; 68:102346. [PMID: 36634595 DOI: 10.1016/j.coph.2022.102346] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 12/02/2022] [Indexed: 01/12/2023]
Abstract
Allogeneic hematopoietic stem cell transplantation is used to treat blood cancers, but often results in lethal graft-versus-host disease (GVHD). GVHD is an inflammatory disorder mediated by donor leukocytes that damage host tissues. Purinergic signalling plays important roles in GVHD development in mice but studies of these pathways in human GVHD remain limited. P2X7 receptor activation by ATP on host antigen presenting cells contributes to the induction of GVHD, while activation of this receptor on regulatory T cells, myeloid-derived suppressor cells and possibly type 3 innate lymphoid cells results in their loss to promote GVHD progression. In contrast, A2A receptor activation by adenosine on donor T cells serves to restrict GVHD development. These and other purinergic signalling molecules remain potential biomarkers and therapeutic targets in GVHD.
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Affiliation(s)
- Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia.
| | - Peter Cuthbertson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Amal Elhage
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Chloe Sligar
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Debbie Watson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
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Watson D, Adhikary SR, Cuthbertson P, Geraghty NJ, Bird KM, Elhage A, Sligar C, Sluyter R. Humanized Mouse Model to Study the P2X7 Receptor in Graft-Versus-Host Disease. Methods Mol Biol 2022; 2510:315-340. [PMID: 35776334 DOI: 10.1007/978-1-0716-2384-8_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Humanized mouse models of graft-versus-host disease (GVHD), where human immune cells are injected into immune deficient mice, are well established and provide opportunities to investigate pathways involved in GVHD development. This chapter provides an overview of human immune cell isolation, injection of these cells into immune deficient mice, monitoring of mice for signs of GVHD, and assessment of human cell engraftment using flow cytometry. Further, this chapter focuses on the P2X7 signaling pathway involved in GVHD, and describes a strategy to block the P2X7 receptor and examine the effect of this on GVHD development.
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Affiliation(s)
- Debbie Watson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.
| | - Sam R Adhikary
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Peter Cuthbertson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Nicholas J Geraghty
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Katrina M Bird
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Amal Elhage
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Chloe Sligar
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
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Adhikary SR, Cuthbertson P, Nicholson L, Bird KM, Sligar C, Hu M, O'Connell PJ, Sluyter R, Alexander SI, Watson D. Post-transplant cyclophosphamide limits reactive donor T cells and delays the development of graft-versus-host disease in a humanized mouse model. Immunology 2021; 164:332-347. [PMID: 34021907 DOI: 10.1111/imm.13374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 05/03/2021] [Accepted: 05/09/2021] [Indexed: 12/27/2022] Open
Abstract
Graft-versus-host disease (GVHD) is a major complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT) that develops when donor T cells in the graft become reactive against the host. Post-transplant cyclophosphamide (PTCy) is increasingly used in mismatched allo-HSCT, but how PTCy impacts donor T cells and reduces GVHD is unclear. This study aimed to determine the effect of PTCy on reactive human donor T cells and GVHD development in a preclinical humanized mouse model. Immunodeficient NOD-scid-IL2Rγnull mice were injected intraperitoneally (i.p.) with 20 × 106 human peripheral blood mononuclear cells stained with carboxyfluorescein succinimidyl ester (CFSE) (day 0). Mice were subsequently injected (i.p.) with PTCy (33 mg kg-1 ) (PTCy-mice) or saline (saline-mice) (days 3 and 4). Mice were assessed for T-cell depletion on day 6 and monitored for GVHD for up to 10 weeks. Flow cytometric analysis of livers at day 6 revealed lower proportions of reactive (CFSElow ) human (h) CD3+ T cells in PTCy-mice compared with saline-mice. Over 10 weeks, PTCy-mice showed reduced weight loss and clinical GVHD, with prolonged survival and reduced histological liver GVHD compared with saline-mice. PTCy-mice also demonstrated increased splenic hCD4+ :hCD8+ T-cell ratios and reduced splenic Tregs (hCD4+ hCD25+ hCD127lo ) compared with saline-mice. This study demonstrates that PTCy reduces GVHD in a preclinical humanized mouse model. This corresponded to depletion of reactive human donor T cells, but fewer human Tregs.
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Affiliation(s)
- Sam R Adhikary
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Peter Cuthbertson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Leigh Nicholson
- Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - Katrina M Bird
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Chloe Sligar
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Min Hu
- Westmead Institute for Medical Research, Westmead, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | | | - Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | | | - Debbie Watson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
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