Journal: bioRxiv

Article Title: A Precision Gene Engineered B Cell Medicine Producing Sustained Levels of Active Factor IX for Hemophilia B Therapy

doi: 10.1101/2025.04.06.647090

Figure Lengend Snippet: Biodistribution of BE-101 in NOG-hIL6 mice was measured by a quantitative polymerase chain reaction (qPCR) method assay designed to detect and quantify the human-specific Alu sequence as a surrogate for human genomic DNA in mouse organs, bone marrow cells, and whole blood samples. (A) Mean human DNA mass detected in femur and spinal column of NOG-hIL6 mouse mice on day 1 and day 28 post IV administration of BE-101 at 20 x 10 6 viable cells/mice. Error bars represent ± standard error of the mean for n = 3 mice on day 1 and day 28. Mann-Whitney U test was used to assess statistical significance; ns = not significant. (B) and (C) Shown are the mean percentages of human genomic DNA detected in (B) bone marrow-containing tissues and (C) whole blood and various NOG-hIL6 mouse organs on day 7 and day 28 relative to the day 1 post IV administration of BE-101 at 20 x 10 6 viable cells/mice. Error bars represent ± coefficient of variation for n = 3 mice at each time point. (D) Schematic of the firefly luciferase transgene for targeted integration at the CCR5 locus. (E) Quantification of bioluminescence signal over time. Each data point represents the mean and the error bars represent ± SEM for n = 3 mice in each group. (F) Bioluminescence imaging of NOG-hIL6 on day 8 and day 44 after a single IV administration of 10 x 10 6 viable non-engineered or luciferase-engineered BCMs on day 1.

Article Snippet: Immunodeficient NOG-hIL6 mice ( NOD.Cg-Prkdcscid Il2rgtm1SugTg(CMV-IL6)1-1Jic/JicTac , Taconic Biosciences Rensselaer, NY) engineered to express a human interleukin 6 (hIL-6) transgene, 8–14-week-old, were housed (up to 3 animals per cage) in a HEPA filtered, individually isolated cage system (Innovive, San Diego, CA) and acclimated for at least 3d.

Techniques: Real-time Polymerase Chain Reaction, Sequencing, MANN-WHITNEY, Luciferase, Imaging

Journal: bioRxiv

Article Title: A Precision Gene Engineered B Cell Medicine Producing Sustained Levels of Active Factor IX for Hemophilia B Therapy

doi: 10.1101/2025.04.06.647090

Figure Lengend Snippet: In vivo secretion of engineered B cell derived FIX-Padua and human IgG after a single administration and repeated administrations of BE-101 in NOG-IL6 mice. A) NOG-hIL-6 mice were dosed with 20×10 6 total viable cells of BE-101 and endogenous B cell derived human IgG and engineered B cell derived FIX-Padua levels were measured in blood plasma up to 196 days of study. B) Data is representative of three individual studies. The lower limit of quantitation (LLOQ) of FIX-Padua protein and human IgG assay is 3.6 ng/ml and 3.4 ng/mL, respectively. C) NOG-hIL6 mice (n =4) were dosed with 20×10 6 total viable cells of BE-101 on day 0 and re-dosed on day 49 of the study. Human IgG and FIX-Padua protein levels were measured in blood plasma after 1 day post BE-101 administration and then weekly up to 77 days of study. D) The lower limit of quantitation (LLOQ) of human FIX-Padua protein and human IgG is 2.5 ng/mL and 0.781 ng/mL, respectively. B) and D) Each data point represents the mean across all groups at that timepoint. The error bars indicate the Standard Error of the Mean (SEM).

Article Snippet: Immunodeficient NOG-hIL6 mice ( NOD.Cg-Prkdcscid Il2rgtm1SugTg(CMV-IL6)1-1Jic/JicTac , Taconic Biosciences Rensselaer, NY) engineered to express a human interleukin 6 (hIL-6) transgene, 8–14-week-old, were housed (up to 3 animals per cage) in a HEPA filtered, individually isolated cage system (Innovive, San Diego, CA) and acclimated for at least 3d.

Techniques: In Vivo, Derivative Assay, Quantitation Assay