CD8+ but not CD4+ T cells require cognate interactions with target tissues to mediate GVHD across only minor H antigens, whereas both CD4+ and CD8+ T cells require direct leukemic contact to mediate GVL

Blood. 2008 Apr 1;111(7):3884-92. doi: 10.1182/blood-2007-11-125294. Epub 2008 Jan 25.

Abstract

Whether T-cell antigen receptors (TCR) on donor T cells require direct interactions with major histocompatibility complex class I or class II (MHCI/MHCII) molecules on target cells to mediate graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) is a fundamental question in allogeneic stem-cell transplantation (alloSCT). In MHC-mismatched mouse models, these contacts were not required for GVHD. However, this conclusion may not apply to MHC-matched, multiple minor histocompatibility antigen-mismatched alloSCT, the most common type performed clinically. To address this, we used wild-type (wt)-->MHCI-/- or wt-->MHCII-/- bone marrow chimeras as recipients in GVHD experiments. For GVL experiments, we used MHCI-/- or MHCII-/- chronic-phase CML cells created by expressing the BCR-ABL cDNA in bone marrow from MHCI-/- or MHCII-/- mice. TCR/MHCI contact was obligatory for both CD8-mediated GVHD and GVL. In contrast, CD4 cells induced GVHD in wt-->MHCII-/- chimeras, whereas MHCII-/- mCP-CML was GVL-resistant. Donor CD4 cells infiltrated affected skin and bowel in wt-->MHCII-/- recipients, indicating that they mediated GVHD by acting locally. Thus, CD4 cells use distinct effector mechanisms in GVHD and GVL: direct cytolytic action is required for GVL but not for GVHD. If these noncytolytic pathways can be inhibited, then GVHD might be ameliorated while preserving GVL.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / pathology
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / pathology
  • Disease Models, Animal
  • Graft vs Host Disease / immunology*
  • Graft vs Host Disease / pathology
  • Graft vs Leukemia Effect / immunology*
  • Histocompatibility Antigens Class I / genetics
  • Histocompatibility Antigens Class I / immunology
  • Histocompatibility Antigens Class II / genetics
  • Histocompatibility Antigens Class II / immunology
  • Humans
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / genetics
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / immunology*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / therapy
  • Mice
  • Mice, Knockout
  • Minor Histocompatibility Antigens / genetics
  • Minor Histocompatibility Antigens / immunology*
  • Receptors, Antigen, T-Cell / genetics
  • Receptors, Antigen, T-Cell / immunology
  • Stem Cell Transplantation*
  • Transplantation Chimera / genetics
  • Transplantation Chimera / immunology
  • Transplantation, Homologous

Substances

  • Histocompatibility Antigens Class I
  • Histocompatibility Antigens Class II
  • Minor Histocompatibility Antigens
  • Receptors, Antigen, T-Cell