title: Fat body and hemocyte contribution to the antimicrobial peptide synthesis in Calliphora vicina R.-D. (Diptera: Calliphoridae) larvae.
abstract: Antimicrobial peptides accumulated in the hemolymph in response to infection are a key element of insect innate immunity. The involvement of the fat body and hemocytes in the antimicrobial peptide synthesis is widely acknowledged, although release of the peptides present in the hemolymph from the immune cells was not directly verified so far. Here, we studied the presence of antimicrobial peptides in the culture medium of fat body cells and hemocytes isolated from the blue blowfly Calliphora vicina using complex of liquid chromatography, mass spectrometry, and antimicrobial activity assays. Both fat body and hemocytes are shown to synthesize and release to culture medium defensin, cecropin, diptericins, and proline-rich peptides. The spectra of peptide antibiotics released by the fat body and hemocytes partially overlap. Thus, the results suggest that insect fat body and blood cells are capable of releasing mature antimicrobial peptides to the hemolymph. It is notable that the data obtained demonstrate dramatic difference in the functioning of insect antimicrobial peptides and their mammalian counterparts localized into blood cells' phagosomes where they exert their antibacterial activity.
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia. andstop@mail.ru.
authors: Andrey Yu
authors: AY
authors: Yakovlev
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia.
authors: Alexander P
authors: AP
authors: Nesin
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia.
authors: Nina P
authors: NP
authors: Simonenko
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia.
authors: Natalia A
authors: NA
authors: Gordya
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia.
authors: Dmitriy V
authors: DV
authors: Tulin
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia.
authors: Anastasia A
authors: AA
authors: Kruglikova
authors: Laboratory of Insect Biopharmacology and Immunology, Department of Entomology, Saint-Petersburg State University, Petrodvoretz, Botanicheskaya st., 17, 198504, Saint-Petersburg, Russia.
authors: Sergey I
authors: SI
authors: Chernysh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology*; D002478:Cells, Cultured; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D003470:Culture Media / Q000494:pharmacology; D004175:Diptera / Q000166:cytology*; D005216:Fat Body / Q000166:cytology*; D006434:Hemocytes / Q000166:cytology*; D007814:Larva / Q000166:cytology / Q000187:drug effects; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects; D008970:Molecular Weight
chemical_list: D023181:Antimicrobial Cationic Peptides; D003470:Culture Media
keywords: Antimicrobial peptides; Cell cultures; Fat body; Hemocytes; Insect immunity