title: Riboflavin as a source of autofluorescence in Eisenia fetida coelomocytes.
abstract: Immunocompetent cells of earthworms (coelomocytes) contain adherent amoebocytes and large eleocytes (chloragocytes); the latter are filled with numerous granules. We have previously shown that eleocytes of several (but not all) earthworm species exhibit strong autofluorescence detectable by fluorescent microscopy and flow cytometry. In the present article, the molecular origin of eleocytes autofluorescence was elucidated in coelomocytes expelled via dorsal pores in the integument of Eisenia fetida subjected to electric shock (1 min at 4.5 V). Spectrofluorometry (excitation and emission spectra and fluorescence lifetime), together with HPLC analysis of coelomocyte suspensions and supernatants, indicated that riboflavin but not FMN (flavin mononucleotide) or FAD (flavin-adenine dinucleotide) is the main fluorophore responsible for eleocyte fluorescence in this species. Additionally, lipofuscins are suspected to participate in this phenomenon.
authors.affiliation: Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, Krakow, Poland.
authors.forename: Beata
authors.initials: B
authors.lastname: Koziol
authors.forename: Magdalena
authors.initials: M
authors.lastname: Markowicz
authors.forename: Jerzy
authors.initials: J
authors.lastname: Kruk
authors.forename: Barbara
authors.initials: B
authors.lastname: Plytycz
mesh_terms: D000818:Animals; D002470:Cell Survival; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D004565:Electroconvulsive Therapy; D005486:Flavin Mononucleotide / Q000737:chemistry; D005182:Flavin-Adenine Dinucleotide / Q000737:chemistry; D005434:Flow Cytometry; D005453:Fluorescence; D008062:Lipofuscin / Q000737:chemistry; D008856:Microscopy, Fluorescence; D009835:Oligochaeta / Q000737:chemistry* / Q000502:physiology; D012256:Riboflavin / Q000737:chemistry*; D013997:Time Factors
chemical_list: D008062:Lipofuscin; D005182:Flavin-Adenine Dinucleotide; D005486:Flavin Mononucleotide; D012256:Riboflavin