Astragalus membranaceus injection delayed allograft survival related with CD4+ CD25+ regulatory T cells

Transplant Proc. 2010 Nov;42(9):3793-7. doi: 10.1016/j.transproceed.2010.08.032.

Abstract

Introduction: Recently it has been reported that Astragalus membranaceus injection (AMI) inhibits immune responses, but whether it affects alloimmunity is not clear. It has been shown that the CD4(+) CD25(+) regulatory T cells (Treg) down-regulate immune responses. The aim of our study was to investigate the effects of AMI on allograft survival and its relation to Treg.

Materials and methods: Allografted mice were administered AMI for 14 consecutive days with observations of graft survival. The specific recall response, the ratio of Treg, the expression of Foxp3 mRNA, and interleukin (IL)-10 secretion were measured by mixed lymphocyte reactions (MLR), FCM, reverse transcriptase-polymerase chain reaction, and radioimmunoassay, respectively.

Results: AMI significantly prolonged allograft survival by up-regulating the Treg ratio and promoting Foxp3 expression (P < .05). The ratio of Tregs, the expression of Foxp3 mRNA, and the IL-10 level in the AMI administration group increased from day 7, to reach a maximum at day 14, recovering to the initial level on day 21. No obvious difference was detected between the AMI and a cyclosporine group.

Conclusion: AMI administered in vivo prolonged allograft survival associated with promotion of Treg activities.

MeSH terms

  • Animals
  • Astragalus propinquus*
  • Cells, Cultured
  • Cyclosporine / administration & dosage
  • Female
  • Flow Cytometry
  • Forkhead Transcription Factors / genetics
  • Graft Rejection / immunology
  • Graft Rejection / prevention & control*
  • Graft Survival / drug effects*
  • Immunologic Memory / drug effects
  • Immunosuppressive Agents / administration & dosage*
  • Injections, Intraperitoneal
  • Interleukin-10 / blood
  • Interleukin-2 Receptor alpha Subunit / analysis*
  • Lymphocyte Culture Test, Mixed
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Plant Preparations / administration & dosage*
  • RNA, Messenger / metabolism
  • Radioimmunoassay
  • Reverse Transcriptase Polymerase Chain Reaction
  • Skin Transplantation*
  • T-Lymphocytes, Regulatory / drug effects*
  • T-Lymphocytes, Regulatory / immunology
  • Time Factors
  • Transplantation, Homologous

Substances

  • Forkhead Transcription Factors
  • Foxp3 protein, mouse
  • IL10 protein, mouse
  • IL2RA protein, human
  • Immunosuppressive Agents
  • Interleukin-2 Receptor alpha Subunit
  • Plant Preparations
  • RNA, Messenger
  • Interleukin-10
  • Cyclosporine