Figure 4. Examples of 2 D gels prepared using protein extracts from the central portions of the anterior body parts of an unfed and a fed leech.

A - unfed leech, B - leech fed pig blood for 30 min just before being prepared. Proteins had been separated according to their pI by isoelectric focussing (horizontal axis) and subsequently according to their masses by SDS electrophoresis (vertical axis) and silver stained. Spots labeled by black circles were regularly present in samples from unfed as well as from recently fed leeches, while spots labeled by red circles were generally present in unfed leeches but absent in fed leeches. Proteins represented by the spots labeled in red were considered to be secretory salivary gland proteins which are mobilized during feeding and transferred to the host.