Fig. 3

Aeromonas secretes a factor that rescues normal expansion of the GF β cell mass.

(A) Total β cell numbers in GF, CV and GF fish treated at 4 dpf with different cell free supernatant (CFS) samples. 'Aero.' refers to bacteria of the genus Aeromonas, with each number (1, 2, 3) denoting a separate species. '+ PK' indicates proteinase K addition to the CFS sample prior to treatment. *p<0.05, **p<0.01, ***p<0.001: Denotes treatment that is significantly different than GF by Tukey analysis. (B) Total β cell numbers in CV, GF and GF fish treated at 4 dpf with separate ammonium sulfate fractions (% AS) prepared from the Aeromonas 1^ΔT2SS CFS. Note that the 60–80% ammonium sulfate fraction resulted in the greatest increase in β cell numbers. (C) Total β cells in GF, CV and GF fish treated with purified protein. 10165 represents purified protein from the M001_10165 locus. (D) Representative 2D slices from confocal scans through the primary islets of GF, CV and 10165 protein treated Tg(-1.0insulin:eGFP) 6 dpf larvae. Insulin promoter expressing β cells are shown in green and nuclei are blue. Scale bar = 40 μM.