Michael Kirsch

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The key components of the intracellular molecular network required for the expression of a specific function of dendritic cells (DCs) are as yet undefined. Using an in vitro model of human monocyte-derived DC differentiation, this study investigates the role of glycogen synthase kinase 3 (GSK-3), a multifunctional enzyme critical for cellular(More)
Amino acid sequence comparison suggests that numerous proteins are common to the signal transduction pathways controlling chemotaxis in Bacillus subtilis and Escherichia coli. However, previous work has indicated several differences between the two systems. We have undertaken a comparative study of the roles of the CheY protein in chemotaxis by B. subtilis(More)
Bacillus subtilis cheRB, which encodes the chemotactic methyltransferase, has been cloned and sequenced. CheRB is a polypeptide of 256 amino acids, with a predicted molecular mass of 28 kDa. A comparison of the predicted amino acid sequence of B. subtilis CheRB with that of Escherichia coli CheRE demonstrates that the two enzymes share 31% amino acid(More)
The Bacillus subtilis gene encoding CheB (cheBB), the chemotactic methylesterase, has been sequenced. The 39-kDa protein which resulted from the expression of cheBB, using a T7 expression system was consistent with the predicted open reading frame. CheBB shares 39.5% identity with Escherichia coli CheBE and can complement a cheBE null mutant. CheBB is(More)
To examine mechanisms of mobilization and homing of hematopoietic progenitor cells, coexpression of CD34 and the adhesion molecules L-selectin (CD62L), VLA-4 (alpha 4 beta 1-integrin, CD49d/CD29), and LFA-1 (alpha L beta 2-integrin, CD11a/CD18) was evaluated. Samples from leukapheresis (LP) products and bone marrow (BM) were obtained on the same day from(More)
Phenotypic maturation, cytokine secretion, and migration are distinct functional characteristics of dendritic cells (DCs). These functions are independently regulated by a number of extracellular variables, such as type, strength, and persistence of an array of soluble and membrane-bound mediators. Since the exact composition of these variables in response(More)
Migration to lymph nodes and secretion of cytokines are critical functions of mature dendritic cells (DCs); however, these 2 functions are not necessarily linked. This is the first report showing that quantitative differences in identical signaling pathways determine DC migration and cytokine secretion. Using different polymerized forms of CD40 ligand, we(More)
Accurate mitotic spindle positioning is essential for the regulation of cell fate choices, cell size and cell position within tissues. The most prominent model of spindle positioning involves a cortical pulling mechanism, where the minus end-directed microtubule motor protein dynein is attached to the cell cortex and exerts pulling forces on the plus ends(More)
A majority of the chemotaxis and flagellar genes of Bacillus subtilis are found in the major che/fla operon which spans over 26 kilobases of DNA and encodes at least 30 genes. In this operon, a single open reading frame, designated orf298, has been demonstrated to encode a 33,131 Dalton protein which shows no evidence of being involved in chemotaxis or(More)
The use of antisense oligodeoxyribonucleotides (ODN) is a potential method to switch off gene expression. The poor cellular uptake of ODN in primary cells still is a limiting factor that may contribute to the lack of functional efficacy. Various forms of cationic lipids have been developed for efficient delivery of nucleic acids into different cell types.(More)