Inhibition of alloantigen-primed memory CD4+ and CD8+ T cells by hematopoietic chimerism in mice

Scand J Immunol. 2010 Aug;72(2):86-93. doi: 10.1111/j.1365-3083.2010.02412.x.

Abstract

Donor-reactive memory T cells present a special hurdle in transplantation. Although hematopoietic chimerism is effective for inducing donor-specific tolerance, the effects on memory T cells are unclear. Here, we induced stable chimerism and tolerance in mice (Tolerance group, n = 6) by donor-specific transfusion (DST) plus anti-CD154 monoclonal antibody (mAb), avoiding the toxic myeloablative conditioning treatment to assist bone marrow transplantation (DST/aCD154&BMTx). We then transferred memory CD4(+) or CD8(+) T cells from donor antigen primed mice to the tolerance-induced recipients 4 days after heart transplantation (Tol/CD4(+) Tm group and Tol/CD8(+) Tm group, n = 6, respectively), but neither of these memory T-cell subsets had an effect on the permanent graft survival (median survival time > 100 days). The unaltered rate of memory T cells in spleen and anergy to donor antigen in vitro demonstrated that these memory T cells were well controlled. The chimerism-promoting protocol DST/aCD154&BMTx produced an immune environment that included high levels of regulatory T cells (Tregs), microchimerism and TGF-beta, all of which may act in suppressing the donor-reactive memory CD4(+) or CD8(+) T cells. These findings have potentially important implications for designing approaches to suppressing memory T cells for success of transplantation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Female
  • Flow Cytometry
  • Forkhead Transcription Factors / chemistry
  • Forkhead Transcription Factors / genetics
  • Graft Survival / immunology
  • Heart Transplantation / immunology*
  • Immunologic Memory / immunology*
  • Interferon-gamma / chemistry
  • Interferon-gamma / genetics
  • Interleukin-2 / chemistry
  • Interleukin-2 / genetics
  • Isoantigens / immunology*
  • Kaplan-Meier Estimate
  • Lymphocyte Culture Test, Mixed
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C3H
  • Mice, Inbred C57BL
  • RNA / chemistry
  • RNA / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Specific Pathogen-Free Organisms
  • Transplantation Chimera

Substances

  • Forkhead Transcription Factors
  • Foxp3 protein, mouse
  • Interleukin-2
  • Isoantigens
  • RNA
  • Interferon-gamma