Preferential priming of alloreactive T cells with indirect reactivity.


Journal Article

The relative contributions of the direct and indirect pathways in alloimmune responses have not been fully elucidated. We report a novel murine TCR transgenic system that can simultaneously track the CD4-direct (CD4-d), CD4-indirect (CD4-i) and CD8-direct (CD8-d) pathways after transplantation. Using this system, we have observed a profoundly greater proliferation of CD4-i T cells relative to CD4-d and CD8-d T cells after transplantation. Furthermore, a much larger proportion of CD4-i T cells attain an effector phenotype. We also analyzed endogenous, wild-type T cells using enzyme-linked immunospot analysis. In naïve mice, T cells with indirect reactivity were undetectable, but T cells with direct reactivity were abundant. However, 10 days after skin or heterotopic heart transplantation, CD4-i T cells comprised approximately 10% of the CD4+ response. Consistent with increased priming of the CD4-i pathway, we observed that the CD4-i T cells were further enriched in the effector cells migrating to the allograft and in memory-like T cells persisting after rejection. Thus, priming of the CD4-i pathway is favored after transplantation, allowing a rare population to rapidly become a major component of the CD4+ T-cell response in acute allograft rejection. The generalizability of this observation to other models remains to be determined.

Full Text

Cited Authors

  • Brennan, TV; Jaigirdar, A; Hoang, V; Hayden, T; Liu, F-C; Zaid, H; Chang, CK; Bucy, RP; Tang, Q; Kang, S-M

Published Date

  • April 2009

Published In

Volume / Issue

  • 9 / 4

Start / End Page

  • 709 - 718

PubMed ID

  • 19344462

Pubmed Central ID

  • 19344462

Electronic International Standard Serial Number (EISSN)

  • 1600-6143

International Standard Serial Number (ISSN)

  • 1600-6135

Digital Object Identifier (DOI)

  • 10.1111/j.1600-6143.2009.02578.x


  • eng