Rainbow trout (Oncorhynchus mykiss) sIgM- leucocytes secrete an interleukin-2 like growth factor after mitogenic stimulation in vitro.
Two secreted proteins were detected in culture supernatants of PHA or PMA stimulated, immunomagnetically separated, sIgM(-) leucocytes of rainbow trout (Oncorhynchus mykiss) with 60kDa and with 12-15kDa (multiple bands). So called conditioned media (CM), containing these proteins, induced significant activation of blood and head kidney leucocytes. Immunomagnetically separated, naive as well as PHA activated sIgM(-) T lymphocytes and LPS prestimulated sIgM(+) B lymphocytes could be identified to be responding to these secreted proteins. Using a monoclonal antibody specific for mouse IL-2 (clone JES6-1A12), one of the multiple 12-15kDa proteins could be stained in Western blots. It was also shown that the induced proliferation was due to this protein in the CM, as the same anti-IL-2 mab was able to block the CM induced proliferation. Furthermore, survival of the IL-2 dependent mouse cell line HT-2 was enhanced after addition of various concentrations of CM. The data presented show, for the first time, that mitogen stimulated trout sIgM(-) leucocytes secrete a cytokine like growth factor sharing functional and structural similarities with mammalian IL-2.
Blohm
Ulrike
U
Department of Biology, University of Rostock, Albert Einstein Str. 3, D-18055, Rostock, Germany. Bernd.Koellner@rie.bfav.de
Siegl
Edda
E
Köllner
Bernd
B
D000818:Animals; D001681:Biological Assay; D015153:Blotting, Western / Q000662:veterinary; D002455:Cell Division / Q000276:immunology; D017077:Culture Media, Conditioned; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D007075:Immunoglobulin M / Q000276:immunology; D018189:Immunomagnetic Separation / Q000662:veterinary; D007376:Interleukin-2 / Q000276:immunology / Q000378:metabolism*; D007962:Leukocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D008297:Male; D051379:Mice; D017686:Oncorhynchus mykiss / Q000276:immunology*; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary
D017077:Culture Media, Conditioned; D007075:Immunoglobulin M; D007376:Interleukin-2; D012333:RNA, Messenger