AmpliTaq and AmpliTaq Gold DNA Polymerase - Applied Biosystems

histopathology. The mucosal immune response was characterized by morphometric analysis oflymphoid follicles and by differentiating lymphocyte populations with antibodies against surfacemarkers. Infecting H. pylori strains were positive for vacAs1 but lacked cagPAI and an active oipAgene. Colonization density was uniform throughout the stomach. Upregulation of IFN-{gamma},IL-1{alpha}, IL-1{beta}, and IL-8 and increased severity of inflammatory infiltrates and fibrosiswere observed in infected cats. The median number and total area of lymphoid aggregates were5 and 10 times greater, respectively, in the stomachs of infected than uninfected cats. Secondarylymphoid follicles in uninfected cats were rare and positive for BLA.36 and B220 but negative forCD3 and CD79{alpha}, whereas in infected cats they were frequent and positive for BLA.36,CD79{alpha}, and CD3 but negative for B220. Upregulation of IFN-{gamma}, IL-1{alpha}, IL-1{beta}, and IL-8 and marked hyperplasia of secondary lymphoid follicles are early consequencesof H. pylori infection in cats. The response appears to be similar to that of infected people,particularly children, can develop independently of the pathogenicity factors cagPAI and oipA,and is not correlated with the degree of colonization density or urease activity.Flieger, A., K. Rydzewski, et al. (2004). "Cloning and Characterization of the Gene Encoding the MajorCell-Associated Phospholipase A of Legionella pneumophila, plaB, Exhibiting Hemolytic Activity."Infect. Immun. 72(5): 2648-2658.http://iai.asm.org/cgi/content/abstract/72/5/2648Legionella pneumophila, the causative agent of Legionnaires' disease, is an intracellularpathogen of amoebae, macrophages, and epithelial cells. The pathology of Legionella infectionsinvolves alveolar cell destruction, and several proteins of L. pneumophila are known to contributeto this ability. By screening a genomic library of L. pneumophila, we found an additional L.pneumophila gene, plaB, which coded for a hemolytic activity and contained a lipase consensusmotif in its deduced protein sequence. Moreover, Escherichia coli harboring the L. pneumophilaplaB gene showed increased activity in releasing fatty acids predominantly from diacylphosphoandlysophospholipids, demonstrating that it encodes a phospholipase A. It has been reportedthat culture supernatants and cell lysates of L. pneumophila possess phospholipase A activity;however, only the major secreted lysophospholipase A PlaA has been investigated on themolecular level. We therefore generated isogenic L. pneumophila plaB mutants and tested thosefor hemolysis, lipolytic activities, and intracellular survival in amoebae and macrophages.Compared to wild-type L. pneumophila, the plaB mutant showed reduced hemolysis of human redblood cells and almost completely lost its cell-associated lipolytic activity. We conclude that L.pneumophila plaB is the gene encoding the major cell-associated phospholipase A, possiblycontributing to bacterial cytotoxicity due to its hemolytic activity. On the other hand, in view of thefact that the plaB mutant multiplied like the wild type both in U937 macrophages and inAcanthamoeba castellanii amoebae, plaB is not essential for intracellular survival of thepathogen.John, M., I. T. Kudva, et al. (2005). "Use of In Vivo-Induced Antigen Technology for Identification ofEscherichia coli O157:H7 Proteins Expressed during Human Infection." Infect. Immun. 73(5):2665-2679.http://iai.asm.org/cgi/content/abstract/73/5/2665Using in vivo-induced antigen technology (IVIAT), a modified immunoscreening technique thatcircumvents the need for animal models, we directly identified immunogenic Escherichia coliO157:H7 (O157) proteins expressed either specifically during human infection but not duringgrowth under standard laboratory conditions or at significantly higher levels in vivo than in vitro.IVIAT identified 223 O157 proteins expressed during human infection, several of which were