Peripheral B-cell reconstitution is higher in T1D than in HC-and RA-derived PI humanized mice. Sublethally irradiated NSG and NSG-pct mice were injected with 1.5 × 105 to 2.7 × 105 BM CD34+ cells and grafted under the kidney capsule with a partially HLA-matched human fetal thymus. (A-C) Human peripheral CD19 levels were measured by flow cytometry in PBMCs every other week (10 HC donors, n = 58 mice; 9 T1D donors, n = 66 mice; 5 RA donors, n = 35 mice). Mean of CD19+ cells among total (mouse plus human) PBMCs is shown over time. Bars represent SEM. *Statistical significance calculated by Sidak’s multiple comparison test. (D-E) Mice were euthanized between weeks 14 and 18 after transplantation and BM and spleen were collected. Mean + SEM of CD19 percentage and number are shown. (F) Mean ± SEM of indicated B-cell subpopulation percentage among total BM CD19+ cells are shown. Animals with less than 1% CD19+ cells were excluded from the analysis. (G) Mean + SEM of relative CD19 median fluorescence intensity (MFI) was calculated as follows: CD19 MFI of the sample divided by CD19 MFI of human PBMC run on the flow cytometer in the same analysis.
