INIBIOLP   05426
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE LA PLATA "PROF. DR. RODOLFO R. BRENNER"
Unidad Ejecutora - UE
artículos
Título:
Alpha hemolysin induces an increase of erythrocytes calcium: A FLIM 2-photon phasor analysis approach
Autor/es:
SUSANA SANCHEZ; LAURA BAKÁS; ENRICO GRATTON; VANESA HERLAX
Revista:
PLOS ONE
Editorial:
PUBLIC LIBRARY SCIENCE
Referencias:
Año: 2011 vol. 6 p. 21127 - 21128
ISSN:
1932-6203
Resumen:
a-hemolysin (HlyA) from Escherichia coli is considered as the prototype of a family of toxins called RTX (repeat in toxin), a
group of proteins that share genetic and structural features. HlyA is an important virulence factor in E. coli extraintestinal
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
group of proteins that share genetic and structural features. HlyA is an important virulence factor in E. coli extraintestinal
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
group of proteins that share genetic and structural features. HlyA is an important virulence factor in E. coli extraintestinal
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
-hemolysin (HlyA) from Escherichia coli is considered as the prototype of a family of toxins called RTX (repeat in toxin), a
group of proteins that share genetic and structural features. HlyA is an important virulence factor in E. coli extraintestinal
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.
E. coli extraintestinal
infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several
cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low
concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells
have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside
the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the
calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed
using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an
increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of
measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and
the heterogeneity of the response observed in individual cells.