CD45-AP specifically associates with CD45, a protein tyrosine phosphatase essential for lymphocyte differentiation and antigen receptor-mediated signal transduction. CD45 is thought to mediate antigen receptor signaling by dephosphorylating regulatory tyrosine residues on Src family protein tyrosine kinases such as Lck. However, the mechanism for regulating CD45 protein tyrosine phosphatase act...

A preclinical model was used to determine if transfection of the interleukin 2 (IL-2) gene into human melanoma cells would augment the response of autologous and allogeneic peripheral blood lymphocytes (PBLs) from melanoma patients. IL-2 gene was transfected into three human melanoma cell lines; secretion of IL-2 from stable transfected cells was confirmed by enzyme-linked immunosorbent assay. ...

Recent experiments (11-13) have shown that antigen-specific, CD8+, CD4- T lymphocytes can be induced to proliferate and become killer cells in the absence of a second population of "helper" CD8-, CD4+ cells. We have studied early events in the activation of CD4+ and CD8+ T cell subsets in the primary mixed leukocyte reaction. Dendritic cells are a major if not essential accessory cell for the a...

Arginine was found to be completely depleted from cell-free supernates of mixed leukocyte cultures suppressed by the addition of excess macrophages. Partial reversal of macrophage-mediated suppression was accomplished by daily addition of a cocktail containing arginine and nonamino acid nutrients. Complete reversal of the suppression was accomplished by the addition of arginine and glucose to t...

We previously demonstrated selective enrichment of major histocompatibility complex (MHC) class II-specific autoreactive T cells in a subset of mouse CD4+ thymocytes. Here we show that a significant fraction of these autoreactive cells in the normal adult thymus expresses NK1.1 and high levels of Ly-6C and also exhibits flexibility in MHC restriction. In normal mice, this NK1.1+Ly-6Chi subfract...

BACKGROUND It is known that cardiopulmonary bypass causes an inflammatory reaction with associated morbidity and mortality. Several anti-inflammatory strategies have been implemented to reduce this response, including leukocyte removal from the circulation using specialized filters. OBJECTIVES The aim of this randomized clinical study was to assess the impact of arterial-line systemic leukocy...

Leukocyte extravasation from the blood into tissues is crucial for normal immune surveillance and in inflammation. Traditionally molecules belonging to selectin, chemokine, integrin, and immunoglobulin super families are thought to mediate the multiple adhesive and activation events needed for a successful emigration cascade. Recently, emerging evidence suggests that enzymes expressed on the su...

Proteinase-activated receptor 2 (PAR2) has been suggested to play a role in inflammatory reactions. Because leukocyte-endothelial cell interactions are critical events during inflammatory reactions, and because PAR2 is expressed both on endothelium and leukocytes, we have examined the effects of PAR2-activating peptides (PAR2-APs) on leukocyte rolling and adhesion in mesenteric venules and on l...