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Updated: May 23, 2026

Intracellular Recording, Sensory Field Mapping, and Culturing Identified Neurons in the Leech, Hirudo medicinalis
Published on: November 4, 2013
Innate and procured immunity inside the digestive tract of the medicinal leech
1Department of Internal Medicine, Section of Infectious Diseases, Yale University School of Medicine, New Haven, CT 06520, USA.
Abstract:
Especially when combined with unique biological adaptations, invertebrate animals provide important insights into innate immunity because the immune response is not complicated by adaptive immunity that vertebrates evolved. One such example is the digestive tract of the medicinal leech, Hirudo verbana, which is unusual in two aspects, it contains a simple microbial community and it stores large amounts of vertebrate blood for a several months. In this review we will discuss aspects of the innate immunity of the leech and from the ingested blood that we term procured immunity to differentiate it from the immunity encoded by the leech genome.
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