Factor VIIIa, the protein cofactor for factor IXa, is comprised of A1, A2, and A3-C1-C2 subunits. Recently, we showed that isolated A2 subunit enhanced the kcat for factor IXa-catalyzed activation of factor X by approximately 100-fold ( approximately 1 min-1), whereas isolated A1 or A3-C1-C2 subunits showed no effect on this rate (Fay, P. J., and Koshibu, K. J. (1998) J. Biol. Chem. 273, 19049-...

Fluorescence resonance energy transfer between cyan fluorescent protein- and yellow fluorescent protein-tagged MHC class I molecules reports on their spatial organization during assembly and export from the endoplasmic reticulum (ER). A fraction of MHC class I molecules is clustered in the ER at steady state. Contrary to expectations from biochemical models, this fraction is not bound to the TA...

Epstein-Barr (EB) virus-specific effector T cell lines were established from nine virus-immune donors positive for the serologically defined HLA-A2 antigen; of these, four lines contained a demonstrable A2-restricted cytotoxic component. When these four effector populations were each tested on the same panel of EB virus-transformed lines from 20 HLA-A2-positive individuals, 16 of the target cel...

We examined the immunogenicity of H-2 class I-restricted and HLA-A2-restricted epitopes through peptide immunization of HLA-A2-transgenic mice that also express mouse H-2 class I molecules. All four of the tested epitopes restricted by H-2 class I robustly elicited T-cell responses, but four of seven epitopes restricted by HLA-A2 did not induce T-cell responses, showing that HLA-A2-restricted p...

Generalizing Jones’s notion of a planar algebra, we have previously introduced an A2-planar algebra capturing the structure contained in the double complex pertaining to the subfactor for a finite SU(3) ADE graph with a flat cell system. We now introduce the notion of modules over an A2-planar algebra, and describe certain irreducible Hilbert A2-TL-modules. We construct an A2-graph planar algeb...

BACKGROUND Both inherited predisposition and platelet hyperreactivity have been associated with ischemic coronary events, but mechanisms that support genetic differences among platelets from different subjects are generally lacking. Associations between the platelet Pl(A2) polymorphism of GP IIIa and coronary syndromes raise the question as to whether this inherited variation may contribute to ...

Traditional atherosclerosis risk factors cannot elucidate the increased prevalence of cardiovascular events in end stage renal disease (ESRD) patients on hemodialysis. A previous study has indicated a strong association of the PI(A1/A2) polymorphism with myocardial infarction, diabetes and renal allograft rejection. In this investigation, we determined the prevalence of the PI(A1/A2) polymorphi...

Cinatrins A, B and C3 inhibited phospholipase A2 purified from rat platelets in a dose-dependent manner. Cinatrin C3, the most potent component (IC50 70 microM), was noncompetitive with a Ki value of 36 microM. Cinatrins B and C3 also inhibited both porcine pancreas and Naja naja venom phospholipase A2. Inhibition of rat platelet phospholipase A2 by cinatrin C3 was independent of Ca2+ and subst...

Thirteen monoclonal antibodies to ppp(A2'p5')nA oligonucleotides have been produced by fusing Y3 myeloma cells with spleen cells of rat hyperimmunized with A2'p5'A succinyl albumin as immunogen. 125I-labeled A2'p5'A succinyl tyrosine methyl ester was used as a labeled probe. Antibodies were detected by their ability to bind the labeled analog and were selected for their affinity for A2'p5'A. Th...