Individuals whose platelets lack dense or alpha-granules suffer various degrees of abnormal bleeding, implying that granule cargo contributes to hemostasis. Despite these clinical observations, little is known regarding the effects of impaired platelet granule secretion on thrombus formation in vivo. In platelets, SNARE proteins mediate the membrane fusion events required for granule cargo rele...

Toxoplasma gondii tachyzoites were isolated from an ocular patient in the Republic of Korea and maintained in the laboratory (designated KI-1). In the present study, its genotype was determined by analyzing dense granule antigen 6 (GRA6) gene and surface antigen 2 (SAG2) gene as typing markers. Digestion of the amplification products of GRA6 and of the 5o and 3o ends of SAG2, respectively, with...

Toxoplasmosis is a worldwide infection which is commonly asymptomatic but can cause serious medical problems in immunocompromised individuals and fetus. The infection also causes considerable economic loss because of abortion in livestock, mostly in sheep and goats. DNA vaccination may be a powerful approach against intracellular parasites such as Toxoplasma gondii. The goal of this study was t...

We present evidence that regulation of dense-core secretory granule biogenesis and hormone secretion in endocrine cells is dependent on chromogranin A (CGA). Downregulation of CGA expression in a neuroendocrine cell line, PC12, by antisense RNAs led to profound loss of dense-core secretory granules, impairment of regulated secretion of a transfected prohormone, and reduction of secretory granul...

Platelets are known to contribute to vascular pathologies, however, their role in inflammatory disorders of the central nervous system (CNS), such as multiple sclerosis (MS) and its mouse model, experimental autoimmune encephalomyelitis (EAE), is thus far poorly defined. Although there is emerging evidence that platelets might accumulate in the CNS parenchyma along with an increased activation ...

Electron microscope study of rat mast cell maturation corroborates certain interpretations of features of mast cell differentiation based on light microscope studies. In addition, the ultrastructural variation observed in the granules of differentiating mast cells suggests that granule formation begins with the elaboration of dense granules about 70 mmicro in diameter inside Golgi vacuoles. The...

To characterize the molecular mechanisms of platelet secretion, we focused on the calcium-induced exocytosis of dense core granules. Platelets contain several known t-SNAREs (soluble N-ethylmaleimide sensitive factor [NSF] attachment protein receptors) such as syntaxins 2, 4, and 7 and SNAP-23 (synaptosomal associated protein 23). By using an in vitro exocytosis assay, we have been able to assi...

diagnosis of toxoplasma gondii (t.gondii) infection is of great medical importance especially for pregnant women and immunosuppressed patients. numerous studies have shown that the recombinant production of several ttoxoplasma antigens, including dense granule antigens (gras) has a great potential as diagnostic reagents. previous studies reported expression of amino terminal gra8 protein in fus...

Hermansky-Pudlak syndrome (HPS) is characterized by oculocutaneous albinism, bleeding diathesis, and other variable symptoms. The bleeding diathesis has been attributed to δ storage pool deficiency, reflecting the malformation of platelet dense granules. Here, we analyzed agonist-stimulated secretion from other storage granules in platelets from mouse HPS models that lack adaptor protein (AP)-3...