Background: Dendritic cells (DCs) are potent antigen presenting cells for triggering of the immune reaction post transplantation. These cells are centrally involved in the initiation of T cell-dependent immune responses. Objective: To compare the level of DC maturation and function in liver transplant recipients with healthy controls. Methods: In this study, twelve peripheral blood samples we...

Tumor-associated macrophages (TAMs), the most abundant infiltrating immune cells in tumor microenvironment, have distinct functions in hepatocellular carcinoma (HCC) progression. CD68⁺ TAMs represent multiple polarized immune cells mainly containing CD86⁺ antitumoral M1 macrophages and CD206⁺ protumoral M2 macrophages. TAMs expression and density were assessed by immunohistochemical staining of...

CTLA4-Ig is an Fc fusion protein containing the extracellular domain of CTLA-4, a receptor known to deliver a negative signal to T cells. CTLA4-Ig modulates T cell costimulatory signals by blocking the CD80 and CD86 ligands from binding to CD28, which delivers a positive T cell costimulatory signal. To engineer CTLA4-Ig variants with altered binding affinity to CD80 and CD86, we employed a high...

To define more clearly the roles of CD80 (RIP-CD80) and CD86 (RIP-CD86) in the activation of autoreactive T cells in vivo, we generated transgenic mice expressing either or both costimulatory molecules on the beta cells of the pancreas. While RIP-CD80 mice do not show any sign of autoimmunity, at the age of 7 mo RIP-CD86 transgenic mice develop a lymphoid infiltrate with both IFN-gamma- and IL-...

CD86 signals directly in a B cell to activate PI3K and increase the rate of IgG(1) production, without affecting germline transcription. However, the mechanism by which CD86 activates PI3K in a B cell and the relevance of CD86 stimulation in vivo remains unknown. We show that the addition of CD28/Ig to CD40 ligand/IL-4-activated wild-type, but not CD86- or CD19-deficient, B cells increased the ...

Our findings using B cells from either wild-type, CD86-deficient, or beta 2-adrenergic receptor (beta2AR)-deficient mice suggest three mechanisms by which the level of IgG1 and IgE production can be increased on a per cell basis. Trinitrophenyl-specific B cells enriched from unimmunized mouse spleens were pre-exposed to Ag and/or the beta 2AR ligand terbutaline for 24 h before being activated b...

The interaction between CD28 and its ligands, CD80 and CD86, is crucial for an optimal activation of antigen-specific T cells. However, the requirement of CD80 or CD86 co-stimulation in Th2 cell differentiation and activation is controversial. Freshly isolated murine CD4+ and CD8+ T cells were incubated with P815 transfectants expressing a similar level of either CD80 or CD86 in the presence of...

Effective vaccine adjuvants must induce expression of major histocompatibility (MHC) class II proteins and the costimulatory molecule CD86 on dendritic cells (DCs). However, some adjuvants elicit production of cytokines resulting in adverse inflammatory consequences. Development of agents that selectively increase MHC class II and CD86 expression without triggering unwanted cytokine production ...

DNA vaccination is known to elicit robust cellular and humoral responses to encoded antigen. The co-administration of costimulatory molecules CD80 (B7-1), CD86 (B7-2) and CD154 (CD40L) has been shown to enhance immune responses in several murine models. The role of specific costimulatory molecules in non-rodent species remains incompletely characterized. In these studies, we demonstrate that th...

Atopic allergic asthma is characterized by activation of Th2-type T cells in the bronchial mucosa. Previous reports have suggested an important role for costimulation through the CD28/CTLA4-CD80/CD86 pathway in allergen activation of T cells in animal models of inhaled allergen challenge. However, human allergen-specific lines and clones were reported to be costimulation independent. We therefo...