2 research outputs found
Visualizing Single-Cell Secretion Dynamics with Single-Protein Sensitivity
Cellular secretion
of proteins into the extracellular environment
is an essential mediator of critical biological mechanisms, including
cell-to-cell communication, immunological response, targeted delivery,
and differentiation. Here, we report a novel methodology that allows
for the real-time detection and imaging of single unlabeled proteins
that are secreted from individual living cells. This is accomplished
via interferometric detection of scattered light (iSCAT) and is demonstrated
with Laz388 cells, an EpsteināBarr virus (EBV)-transformed
B cell line. We find that single Laz388 cells actively secrete IgG
antibodies at a rate of the order of 100 molecules per second. Intriguingly,
we also find that other proteins and particles spanning ca. 100 kDaā1
MDa are secreted from the Laz388 cells in tandem with IgG antibody
release, likely arising from EBV-related viral proteins. The technique
is general and, as we show, can also be applied to studying the lysate
of a single cell. Our results establish label-free iSCAT imaging as
a powerful tool for studying the real-time exchange between cells
and their immediate environment with single-protein sensitivity
Visualizing Single-Cell Secretion Dynamics with Single-Protein Sensitivity
Cellular secretion
of proteins into the extracellular environment
is an essential mediator of critical biological mechanisms, including
cell-to-cell communication, immunological response, targeted delivery,
and differentiation. Here, we report a novel methodology that allows
for the real-time detection and imaging of single unlabeled proteins
that are secreted from individual living cells. This is accomplished
via interferometric detection of scattered light (iSCAT) and is demonstrated
with Laz388 cells, an EpsteināBarr virus (EBV)-transformed
B cell line. We find that single Laz388 cells actively secrete IgG
antibodies at a rate of the order of 100 molecules per second. Intriguingly,
we also find that other proteins and particles spanning ca. 100 kDaā1
MDa are secreted from the Laz388 cells in tandem with IgG antibody
release, likely arising from EBV-related viral proteins. The technique
is general and, as we show, can also be applied to studying the lysate
of a single cell. Our results establish label-free iSCAT imaging as
a powerful tool for studying the real-time exchange between cells
and their immediate environment with single-protein sensitivity