CFTR regulates phagosome acidification in macrophages and alters bactericidal activity.
AuthorsDi A, Brown ME, Deriy LV, Li C, Szeto FL, Chen Y, Huang P, Tong J, Naren AP, Bindokas V, Palfrey HC, Nelson DJ
JournalNat Cell Biol
PubMed ID16921366
'Acidification of phagosomes has been proposed to have a key role in the microbicidal function of phagocytes. Here, we show that in alveolar macrophages the cystic fibrosis transmembrane conductance regulator Cl- channel (CFTR) participates in phagosomal pH control and has bacterial killing capacity. Alveolar macrophages from Cftr-/- mice retained the ... More
Characterization of intracellular pH gradients in human multidrug-resistant tumor cells by means of scanning microspectrofluorometry and dual-emission-ratio probes.
AuthorsBelhoussine R, Morjani H, Sharonov S, Ploton D, Manfait M
JournalInt J Cancer
PubMed ID10077157
'Multidrug-resistant cells are believed to contain a plasma-membrane-efflux pump which is hypothesized to expel anticancer drugs from the cytosol to the cell exterior. Many of these drugs are classified as weak bases whose binding to intracellular targets is pH-dependent. Slight alterations in intracellular pH gradients have been shown to affect ... More
Activation of trypsinogen in large endocytic vacuoles of pancreatic acinar cells.
'The intracellular activation of trypsinogen, which is both pH- and calcium-dependent, is an important early step in the development of acute pancreatitis. The cellular compartment in which trypsinogen activation occurs currently is unknown. We therefore investigated the site of intracellular trypsinogen activation by using an established cellular model of acute ... More
Individual acidic organelle pH measurements by capillary electrophoresis.
AuthorsChen Y, Arriaga EA
JournalAnal Chem
PubMed ID16448056
'This report describes the pH measurement of individual acidic organelles isolated from the human leukemia CCRF-CEM and CEM/C2 cells. These cells were allowed to endocytose fluorescein tetramethylrhodamine dextran (FRD), a ratiometric probe that has fluorescein as a pH-dependent fluorophore and tetramethylrhodamine as a pH-independent fluorophore. Isolated organelle fractions from these ... More
Individual electrophoretic mobilities of liposomes and acidic organelles displaying pH gradients across their membranes.
AuthorsChen Y, Arriaga EA
JournalLangmuir
PubMed ID17402758
This report focuses on measuring the individual electrophoretic mobilities of liposomes with different pH gradients across their membrane using capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). The results from the individual analysis of liposomes show that, using surface electrostatic theories and the electrokinetic theory as the first approximation, zeta potential ... More