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Targeted single-cell microchemical analysis: MS-based peptidomics of individual paraformaldehyde-fixed and immunolabeled neurons.

ABSTRACT: Pinpointing a specific cell from within a relatively uniform cell population to determine its chemical content presents a challenging bioanalytical task. Immunocytochemistry is the classical method used to localize specific molecules and, hence, selected cells. Mass spectrometry also probes endogenous molecules such as neuropeptides within a cell. Here, these two approaches are hyphenated to allow microchemical analysis of immunocytochemical-selected peptidergic neurons. This two-step strategy utilizes antibody-based localization of cells containing selected biomarkers to isolate the cell(s) of interest, followed by peptidomic analysis via mass spectrometry. Applicable to a broad range of analyte and cell types, the strategy was used to successfully profile neuropeptides from individual immunostained insect neurons stored for up to 2 weeks as well as from tissues preserved for 42 weeks.

SUBMITTER: Neupert S

PROVIDER: S-EPMC3566229 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Targeted single-cell microchemical analysis: MS-based peptidomics of individual paraformaldehyde-fixed and immunolabeled neurons.

Neupert Susanne S Rubakhin Stanislav S SS Sweedler Jonathan V JV

Chemistry & biology 20120801 8

Pinpointing a specific cell from within a relatively uniform cell population to determine its chemical content presents a challenging bioanalytical task. Immunocytochemistry is the classical method used to localize specific molecules and, hence, selected cells. Mass spectrometry also probes endogenous molecules such as neuropeptides within a cell. Here, these two approaches are hyphenated to allow microchemical analysis of immunocytochemical-selected peptidergic neurons. This two-step strategy u ...[more]

PMID: 22921068

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