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Updated: Jul 27, 2026

Generation of Human CD40-activated B cells
13:27

Generation of Human CD40-activated B cells

Published on: October 16, 2009

Help for cytotoxic-T-cell responses is mediated by CD40 signalling

S R Bennett1, F R Carbone, F Karamalis

  • 1Immunology Division, The Walter and Eliza Hall Institute of Medical Research, PO The Royal Melbourne Hospital, Victoria, Australia.

Nature
|June 12, 1998
PubMed

Cytotoxic T lymphocytes (CTLs) which carry the CD8 antigen recognize antigens that are presented on target cells by the class I major histocompatibility complex. CTLs are responsible for the killing of antigen-bearing target cells, such as virus-infected cells. Although CTL effectors can act alone when killing target cells, their differentiation from naive CD8-positive T cells is often dependent on 'help' from CD4-positive helper T (TH) cells. Furthermore, for effective CTL priming, this help must be provided in a cognate manner, such that both the TH cell and the CTL recognize antigen on the same antigen-presenting cell. One explanation for this requirement is that TH cells are needed to convert the antigen-presenting cell into a cell that is fully competent to prime CTL. Here we show that signalling through CD40 on the antigen-presenting cells can replace the requirement for TH cells, indicating that T-cell 'help', at least for generation of CTLs by cross-priming, is mediated by signalling through CD40 on the antigen-presenting cell.

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