Does CD40 Ligation Induce B Cell Negative Selection?

Does CD40 ligation induce B cell negative selection?

Binding of CD154 to its receptor, CD40, provides costimulation for mature B cell activation and differentiation in response to Ag receptor signals. In mice, early B cell precursors express CD40, but its function at this stage is unknown. We examined the effects of CD40 ligation during B cell ontogeny in transgenic mice constitutively expressing CD154 on B cells (kappaEP-CD154). Precursors beyon...

Differential c-Myc responsiveness to B cell receptor ligation in B cell-negative selection.

Responsiveness of c-Myc oncogene to B cell receptor ligation has been implicated in the induction of apoptosis in transformed and normal immature B cells. These studies provided compelling evidence to link the c-Myc oncogene with the process of negative selection in B-lymphocytes. However, in addition to apoptosis, B cell-negative selection has been shown to occur by secondary Ig gene rearrange...

Selection Receptor Ligation in B Cell - Negative Differential c - Myc Responsiveness to B Cell

In vivo CD40 ligation can induce T-cell-independent antitumor effects that involve macrophages.

We have previously demonstrated T cell-independent antitumor and antimetastatic effects of CD40 ligation that involved natural killer (NK) cells. As CD40 molecules are expressed on the surface of macrophages (Mphi), we hypothesized that Mphi may also serve as antitumor effector cells when activated by CD40 ligation. Progression of subcutaneous NXS2 murine neuroblastomas was delayed significantl...

Molecular mechanisms regulating B-cell negative selection.

The commitment of a pluripotential stem cell to the B-cell lineage and the progression of the committed B-cell precursor to a mature, immunocompetent B-cell is a highly regulated process. Extrinsic processes and internal programmes initiate and regulate the changes in gene expression that alter the phenotype and functional characteristics of the B-cell as it proceeds through its maturation. Man...