biostudies-literatureUnknown17(9)den Braanker DRecurrence of proteinuria after kidney transplantation in primary focal segmental glomerulosclerosis (FSGS) is unpredictable. Several putative circulating permeability factors (CPFs) have been suggested, but none have been validated. A clinically relevant experimental model is required that demonstrates the presence of CPF(s) in patient material, to study CPF(s) and possibly predict recurrence in patients. We aimed to develop a FSGS-prone Thy-1.1 transgenic mouse model with accelerated proteinuria after injection of samples from patients with FSGS. The Thy-1.1 transgene was backcrossed into 5 mouse strains. The age of onset and severity of spontaneous proteinuria varied between the different genetic backgrounds. 129X1/SvThy-1.1 and 129S2/SvPasThy-1.1 mice displayed proteinuria at 4 weeks, PloS onee0274959https://www.ebi.ac.uk/biostudies/studies/S-EPMC9499224biostudies-literatureNovel mouse strains to study circulating permeability factor(s) in primary focal segmental glomerulosclerosis.PMC9499224Maas RNijenhuis Tvan der Vlag JSmeets Bden Braanker DDeegens JWetzels JParr NfalseNovel mouse strains to study circulating permeability factor(s) in primary focal segmental glomerulosclerosis.Recurrence of proteinuria after kidney transplantation in primary focal segmental glomerulosclerosis (FSGS) is unpredictable. Several putative circulating permeability factors (CPFs) have been suggested, but none have been validated. A clinically relevant experimental model is required that demonstrates the presence of CPF(s) in patient material, to study CPF(s) and possibly predict recurrence in patients. We aimed to develop a FSGS-prone Thy-1.1 transgenic mouse model with accelerated proteinuria after injection of samples from patients with FSGS. The Thy-1.1 transgene was backcrossed into 5 mouse strains. The age of onset and severity of spontaneous proteinuria varied between the different genetic backgrounds. 129X1/SvThy-1.1 and 129S2/SvPasThy-1.1 mice displayed proteinuria at 4 weeks, 2022-01-01T00:00:00Z20222025-04-18T20:53:06.658Z2025-04-07T08:58:07.769ZS-EPMC94992243613716610.1371/journal.pone.0274959