CD40 and CD154 (CD40 ligand) are surface molecules that are central to the cross-talk between T cells and antigen-presenting cells. This article reviews the relevance of CD40-CD154 interaction for regulation of interleukin-12/interferon-gamma production in response to Toxoplasma gondii as an example of an intracellular pathogen. The manner in which defects in CD154 signaling contribute to immun...

CD40 is an important costimulatory molecule for B cells as well as dendritic cells, monocytes, and other APCs. The ligand for CD40, CD154, is expressed on activated T cells, NK cells, mast cells, basophils, and even activated B cells. Although both CD40(-/-) and CD154(-/-) mice have impaired ability to isotype switch, form germinal centers, make memory B cells, and produce Ab, it is not entirel...

Genetically susceptible C57BL/6 (B6) mice that are infected with the LP-BM5 isolate of murine retroviruses develop profound splenomegaly, lymphadenopathy, hypergammaglobulinemia, terminal B-cell lymphomas, and an immunodeficiency state bearing many similarities to the pathologies seen in AIDS. Because of these similarities, this syndrome has been called murine AIDS (MAIDS). We have previously s...

The interaction of CD40 expressed by immunocompetent cells with its ligand CD154 on the surface of T-helper cells plays a crucial role in the immune response. Recently, the presence of CD40 was also demonstrated on a variety of carcinomas. Whereas the critical relevance of CD40 in cytotoxic T-cell priming via dendritic cells is already established, the biological role of CD40/CD154 interactions...

CD40 ligand (CD154) expression on activated T cells can be separated into an early TCRdependent phase, which occurs between 0 and 24 h after activation, and a later extended phase, which occurs after 24 h and is reciprocally regulated by the cytokines IL-4 and IL-12. IL-4 represses, whereas IL-12 sustains CD154 expression. Consistent with this, Th1, but not Th2, cells express CD154 for extended...

CD40 ligand (CD154) expression on activated T cells can be separated into an early TCR-dependent phase, which occurs between 0 and 24 h after activation, and a later extended phase, which occurs after 24 h and is reciprocally regulated by the cytokines IL-4 and IL-12. IL-4 represses, whereas IL-12 sustains CD154 expression. Consistent with this, Th1, but not Th2, cells express CD154 for extende...

BACKGROUND Blockade of CD40-CD40 ligand (CD154) interactions protects against renal injury in adriamycin nephropathy (AN) in immunocompetent mice. To investigate whether this protection relied on adaptive or cognate immunity, we tested the effect of CD40-CD154 blockade in severe combined immunodeficient (SCID) mice. METHODS SCID mice were divided into three groups: normal, AN + hamster IgG (A...

BACKGROUND AND OBJECTIVES The CD40-CD40L system has pleiotropic effects in a variety of cells and biological processes including the immune response. Within the immune system, these molecules represent a critical link between its humoral and cellular arms. Immune or idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by antibody-induced platelet destruction and cle...

CD40, CX3CL1 and TNF-α promote atheroma and neointima formation. CD40 and TNF-α are also central to the development of diabetic retinopathy while CX3CL1 may play a role in the pathogenesis of this retinopathy. The purpose of this study was to examine whether CD40 ligation increases CX3CL1 and TNF-α protein expression in human endothelial cells from the aorta and retina. CD154 (CD40 ligand) upre...

Patients with chronic lymphocytic leukemia (CLL) treated with adenovirus CD154 (Ad-CD154, CD40 ligand [CD40L]) gene therapy experienced rapid reductions in leukemia cell counts and lymph node size associated with the induced expression of Fas (CD95). However, CLL cells initially resist CD95-mediated apoptosis within the first 3 days after CD40 ligation in vitro. Thereafter, they become sensitiv...