Amir Aghajanian: A novel role for reactive oxygen species in the regulation of RhoA; implications for endothelial permeability and leukocyte transmigration. The endothelial lining of the vasculature plays a critical role in regulating the passage of fluid, macromolecules, and cells between the blood and surrounding tissues. Vascular permeability is tightly regulated and is modulated during both...

Tuberculosis (TB) remains one of the most important infectious diseases of man and animals, and the only available vaccine (BCG) requires urgent replacement or improvement. To facilitate this, the protective mechanisms induced by BCG require further understanding. As a live attenuated vaccine, persistence of BCG bacilli in the host may be a crucial mechanism. We have investigated the long term ...

Transendothelial migration (TEM) is a tightly regulated process whereby leukocytes migrate from the vasculature into tissues. Rho guanosine triphosphatases (GTPases) are implicated in TEM, but the contributions of individual Rho family members are not known. In this study, we use an RNA interference screen to identify which Rho GTPases affect T cell TEM and demonstrate that RhoA is critical for...

We propose to analyze the aperture and ITO layer presence of a modified transverse electromagnetic (TEM) cell. This TEM cell can be used to study the potential effects of microwave electromagnetic fields on biological cells. This modified delivery device allows real-time observation of biological cells during exposure. Microscopic observation is achieved through an aperture in the lower wall of...

Research in cell biology demands advanced microscopy techniques such as confocal fluorescence microscopy (FM), super-resolution microscopy (SRM) and transmission electron microscopy (TEM). Correlative light and electron microscopy (CLEM) is an approach to combine data on the dynamics of proteins or protein complexes in living cells with the ultrastructural details in the low nanometre scale. To...

BACKGROUND & AIMS Systemic cellular immunity elicited by the Ty21a oral typhoid vaccine has been extensively characterized. However, very limited data are available in humans regarding mucosal immunity at the site of infection (terminal ileum [TI]). Here we investigated the host immunity elicited by Ty21a immunization on terminal ileum-lamina propria mononuclear cells (LPMC) and peripheral bloo...

Phenotypic mutations are amino acid changes caused by mistranslation. How phenotypic mutations affect the adaptive evolution of new protein functions is unknown. Here we evolve the antibiotic resistance protein TEM-1 towards resistance on the antibiotic cefotaxime in an Escherichia coli strain with a high mistranslation rate. TEM-1 populations evolved in such strains endow host cells with a gen...

Necrotizing enterocolitis (NEC) is an inflammatory disease with evidence of increased production of proinflammatory cytokines in the intestinal mucosa. Lactobacillus reuteri DSM 17938 (LR17938) has been shown to have anti-inflammatory activities in an experimental model of NEC. Activated effector lymphocyte recruitment to sites of inflammation requires the sequential engagement of adhesion mole...

Dysfunction in effector memory has been proposed to contribute to autoimmunity in type 1 diabetes (T1D). Using a unique cohort of age- and sex-matched T1D patients, nonaffected siblings, and unrelated control children, we undertook a detailed analysis of proliferation, activation, effector responses, and apoptosis in reactivated CD4(+)Tm cells during T-cell receptor stimulation. Across cohorts,...

The majority of Helicobacter pylori reside on gastric epithelial cell surfaces and in the overlying mucus, but a small fraction of H. pylori enter host epithelial and immune cells. To explore the role of the nudA invasin in host cell entry, a ΔnudA deletion derivative of strain J99 was constructed and transformants were verified by PCR and by fluorescence in situ hybridization. AGS cells were i...