title: A2B5-reactive ganglioside expression determines the differentiation stage and capacity of rat insulinoma (RIN) sublines.
abstract: We have generated rat insulinoma (RIN) sublines AlGh, m5F, A12, A13 and AhGh with increasing surface expression of the A2B5 ganglioside, a marker of differentiation. We asked whether the capacity of the sublines to differentiate was related to their stage of differentiation, as is characteristic of cells within the normal beta-cell lineage. To answer this, we measured the effect of the differentiation inducer sodium butyrate (NaB, 1 mM) on proliferation, insulin content, secretion and biosynthesis, and the expression of A2B5 and 3G5 gangliosides by the sublines. Six days after exposure to NaB, cell numbers/dish ranged from (1-3) x 10(6) compared to (4-6) x 10(6) in control cultures. By day 2, AlGh, m5F, A12, A13 and AhGh cells exposed to NaB contained 1.5-, 1.4-, 1.4-, 1.2- and 1.0-fold higher amounts of insulin, respectively, and by day 6, 3.6-, 2.3- and 1.0-fold higher, and 1.2- and 2.4-fold lower, amounts of insulin, respectively, than control cells. After 2 days, insulin secretion from AlGh, m5F, A12, A13 and AhGh cells was 1.7-, 1.0-, 1.5-, 1.0- and 1.0-fold higher, respectively, and the rate of (pro)insulin biosynthesis 1.7-, 2.3-, 1.3-, 1.0- and 1.0-fold higher, respectively, than control cells. After 6 days, A2B5 ganglioside expression was increased 3-, 1.9- and 2-fold on m5F, A12 and A13 cells, respectively, but was not significantly altered on AlGh and AhGh cells. 3G5 ganglioside expression was increased 1.5- and 8.4-fold, respectively, on AlGh and m5F cells, but was unaltered on A12, A13 and AhGh cells.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Burnet Clinical Research Unit, Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Parkville, Australia.
authors.forename: R K
authors.initials: RK
authors.lastname: Bartholomeusz
authors.forename: I L
authors.initials: IL
authors.lastname: Campbell
authors.forename: L C
authors.initials: LC
authors.lastname: Harrison
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division; D002460:Cell Line; D002999:Clone Cells; D005732:Gangliosides / Q000096:biosynthesis*; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000166:cytology*; D051381:Rats
chemical_list: D005732:Gangliosides; D007328:Insulin; C062875:ganglioside A2B5