Determination of sialic acids in immune system cells (coelomocytes) of sea urchin, Paracentrotus lividus, using capillary LC-ESI-MS/MS.
Coelomocytes are considered to be immune effectors of sea urchins. Coelomocytes are the freely circulating cells in the body fluid contained in echinoderm coelom and mediate the cellular defence responses to immune challenges by phagocytosis, encapsulation, cytotoxicity and the production of antimicrobial agents. Coelomocytes have the ability to recognize self from non-self. Considering that sialic acids play important roles in immunity, we determined the presence of sialic acid types in coelomocytes of Paracentrotus lividus. Homogenized coelomocytes were kept in 2 M aqueous acetic acid at 80 °C for 3 h to liberate sialic acids. Sialic acids were determined by derivatization with 1,2-diamino-4,5-methylenediaoxy-benzene dihydrochloride (DMB) followed by capillary liquid-chromatography-electrospray ionization/tandem mass spectrometry (CapLC-ESI-MS/MS). Standard sialic acids; Neu5Ac, Neu5Gc, KDN and bovine submaxillary mucin showing a variety of sialic acids were used to confirm sialic acids types. We found ten different types of sialic acids (Neu5Gc, Neu5Ac, Neu5Gc9Ac, Neu5Gc8Ac, Neu5,9Ac2, Neu5,7Ac2, Neu5,8Ac2, Neu5,7,9Ac3, Neu5Gc7,9Ac2, Neu5Gc7Ac) isolated in limited amounts from total coelomocyte population. Neu5Gc type of sialic acids in coelomocytes was the most abundant type sialic acid when compared with other types. This is the first report on the presence of sialic acid types in coelomocytes of P. lividus using CapLC-ESI-MS/MS-Ion Trap system (Capillary Liquid Chromatography-Electrospray Ionization/Tandem Mass Spectrometry).
Ege University, Faculty of Science, Department of Biology, Section of Molecular Biology, 35100 Bornova-Izmir, Turkey. Electronic address: savas.izzetoglu@ege.edu.tr.
Savaş
S
İzzetoğlu
Ege University, Faculty of Science, Department of Biology, Section of Molecular Biology, 35100 Bornova-Izmir, Turkey.
Umut
U
Şahar
Ege University, Faculty of Science, Department of Biology, Section of Molecular Biology, 35100 Bornova-Izmir, Turkey.
Ecem
E
Şener
Ege University, Faculty of Science, Department of Biology, Section of Molecular Biology, 35100 Bornova-Izmir, Turkey.
Remziye
R
Deveci
D000818:Animals; D002853:Chromatography, Liquid; D007107:Immune System / Q000737:chemistry* / Q000166:cytology / Q000276:immunology; D047328:Paracentrotus / Q000737:chemistry* / Q000166:cytology / Q000276:immunology; D012794:Sialic Acids / Q000032:analysis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D012794:Sialic Acids
CapLC-ESI-MS/MS; Coelomocytes; Echinoderm immune system; Paracentrotus lividus; Sialic acids