Adenosine has been established as an important regulator of immune activation. It signals through P1 adenosine receptors to suppress activation of T cells and professional APCs. Adenosine deaminase (ADA) counters this effect by catabolizing adenosine. This regulatory mechanism has not been tested in a disease model in vivo. Questions also remain as to which cell types are most sensitive to this...

The inositol 1,4,5-trisphosphate receptor (InsP(3)R) is activated by InsP(3) binding to amino-terminal ligand binding domain (InsP(3)R-N). Recently we reported functional coupling of phosphatidylinositol (4, 5)-bisphosphate (PIP(2)) to the InsP(3)R. Specific binding of PIP(2) to InsP(3)R-N domain was postulated as a part of the InsP(3)R-PIP(2) functional coupling model. Here we utilized bacteri...

CD26 is a lymphocyte marker that can anchor adenosine deaminase (ADA) on the T cell surface. We found that ADA is regulated by cytokines on the cell surface during T cell activation. By means of flow cytometry, immunofluorescence, and immunoblotting techniques, we found that interleukin (IL)-2 and IL-12 up-regulate ecto-ADA and CD26 expression. In clear contrast, IL-4 led to down-regulation of ...

Deficiency of erythrocytic and lymphocytic adenosine deaminase (ADA) occurs in some patients with severe combined immunodeficiency disease (SCID). SCID with ADA deficiency is inherited as an autosomal recessive trait. ADA is markedly reduced or undetectable in affected patients (homozygotes), and approximately one-half normal levels are found in individuals heterozygous for ADA deficiency. The ...

Adenosine is a signaling nucleoside that is generated in response to cellular injury and orchestrates the balance between tissue protection and the progression to pathological tissue remodeling. Adenosine deaminase (ADA)-deficient mice develop progressive airway inflammation and remodeling in association with adenosine elevations, suggesting that adenosine can promote features of chronic lung d...

Neurons immunoreactive for the enzyme adenosine deaminase (ADA) in the posterior basal hypothalamus of the rat have a distribution pattern similar to those immunoreactive for histidine decarboxylase (HDC) and are particularly numerous in the tuberal (TM), caudal (CM) and postmammillary caudal (PCM) hypothalamic magnocellular nuclei which harbor neurons containing glutamic acid decarboxylase (GA...

Genetic variation of the enzyme, adenosine deaminase (ADA), can be detected by starch gel electrophoresis of human red cell lysates and an appropriate staining procedure (Spencer, Hopkinson, and Harris, 1968). Three phenotypes (ADA 1, ADA 2-1, and ADA 2) appear to be determined by two structural alleles, ADA' and ADA2. The frequency of the less common allele, ADA2, was reported to be 0 03 and 0...

BACKGROUND This study was conducted to evaluate the feasibility of long-term adalimumab (ADA) discontinuation after achievement of low disease activity (LDA) in Japanese patients with early rheumatoid arthritis (RA) and to identify predictors of LDA maintenance. METHODS In the HOPEFUL-1 study, patients received initial therapy with either ADA plus methotrexate (MTX; intensive therapy) or MTX ...

1-Adamantanamine hydrochloride (Ada) has been reported to be an effective agent against influenza and rubella viruses (1-3). In the course of pharmacological study of Ada in this laboratory it was observed that the compound induced cardiac arrhythmia in rabbit. This was confirmed by Kaji et al. (4). In the present experiment, the mechanism of arrhythmia inducing action of Ada was studied using ...