CD8 T cell priming by B lymphocytes is CD4 help dependent

Eur J Immunol. 2005 May;35(5):1360-70. doi: 10.1002/eji.200425530.


While it is generally accepted that B lymphocytes can present antigen and activate CD4 T cells, priming of CD8 T cells by B lymphocytes remains controversial. Recently, we showed that mice injected with genetically programmed B lymphocytes generate antigen specific CD4 and CD8 T cell responses in vivo that could also be induced in mice lacking functional dendritic cells. To gain further insights into the requirements for T cell priming by antigen-presenting B lymphocytes, in vitro experiments were performed using ovalbumin (OVA) and OVA-specific TCR-transgenic CD4 and CD8 T cells. We found that while B lymphocytes can directly prime CD4 T cells, the activation of CD8 T cells requires T cell help. Transfer experiments show that help can either be contact dependent or be mediated by soluble factors in the supernatants of activated OVA-specific CD4 T cells. Furthermore, the effect of activated CD4 T cells can be replaced by soluble recombinant IL-4. Collectively, the data show the existence of different requirements for priming of CD4 and CD8 T cells and point to the previously unappreciated fact that the induction of CD8 T cell responses by B lymphocytes requires T cell help.

Publication types

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

MeSH terms

  • Animals
  • Antigen Presentation / immunology
  • B-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cell Communication / immunology
  • Interleukin-4 / immunology
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Transgenic
  • Time Factors


  • Interleukin-4