The purpose of the study was to compare the growth of various PDX models in the two ultraimmunodeficient mouse models NSG™ (Jackson Laboratory) and B-NDG (Inotiv). Four breast cancer PDX models from the Washington University Human in Mouse (WHIM) collection, ER+ WHIM20 and WHIM81, Her2+ WHIM43, and triple negative WHIM5, and one melanoma PDX models generated by the Wistar institute, WM4071-2, was utilized. For models WHIM20, WHIM5, and WM4071-2 all mice were injected with tumor cells on the same day, whereas for WHIM43 BND-G mice were injected in two separate batches. The WHIM81 studies were carried out at different times for the NSG™ and B-NDG animal cohorts. Studies utilizing WHIM5, WHIM20, WHIM43 and WM4071-2, included a group of athymic nude mice as well. For all models, mice were injected with 1.5x106 cells/mouse. The cells were mixed 1:1 with PBS:Corning Matrigel GFR and the injection volume was 100 µL/mouse. Mice were housed in Innovive individually vented cages and consumed Teklad Global Rodent Diet 2019 throughout the study. Tumors were measured multiple times per week using Biopticon’s TumorImager™. For all models except WHIM81, the tumors grew well and with very similar rate in both B-NDG and NSG™ mice. WHIM20 and WHIM43 grew significantly slower in the Athymic nude mice compared to both of the ultraimmunodeficient mouse models, however, the growth of WHIM5 was comparable between all three models. The results from the WHIM81 model suggests faster growth in the B-NDG model compared to the NSG™, however, it is also possible that this is due to the different batches of tumor cells utilized at each implantation event. Thus, the B-NDG model represents a novel ultraimmunodeficient mouse model that can have great utility for tumor studies, particularly for hard to grow or slower growing tumor models.

Citation Format: Michele Melton, Hongmei Jiang, Emma M. Hyddmark, Travis Rothrock. PDX tumor growth comparisons in the ultra-immunodeficient NOD.CB17-PrkdcscidIL2rgtm1/Bcgen (B-NDG) mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3114.