Figure 1.

Representative mass spectra acquired from individual α-, β-, γ-, and δ-cells, as well as an intact islet of Langerhans collected from the dorsal pancreas. Peptide cell-type qualifiers/biomarkers: glucagon m/z 3481.5 (α-cells), insulin m/z 5799.9 (β-cells), PP m/z 4397.2 (γ-cells), and somatostatin-14 m/z 1637.7 (δ-cells). These signals are highlighted with asterisks. Many other characteristic signals were observed in the cells as described herein.