The nuNPG strain is a severely immunodeficient mouse model established on the inbred NOD genetic background, carrying mutations in the Prkdctm1Ming and IL2rgtm1Ming genes.

The Prkdctm1Ming mutation is a knockout (KO) mutation achieved by deleting exons 2-10 of the Prkdc gene, which blocks the development of T and B cells and induces immunodeficiency. Compared to the naturally occurring PrkdcSCID mutation found in SCID mice, the Prkdctm1Ming mutation does not exhibit the drawback of low-level "leaky" Prkdc expression with increasing age, which leads to partial immune system recovery in PrkdcSCID mutants. The IL2rgtm1Ming mutation is a KO mutation of the IL2rg gene （deletion of exons 3-6）, which encodes the common cytokine receptor gamma chain. IL2rg, also known as the interleukin-2 receptor subunit gamma, is a shared receptor subunit for interleukins (IL-2, IL-4, IL-7, IL-9, and IL-15). This gene is essential for the differentiation and function of many hematopoietic cells and is crucial for the development of natural killer (NK) cells. On the NOD inbred mouse background, the combination of the Prkdctm1Ming and IL2rgtm1Ming mutations induces a severe immunodeficiency characterized by the absence of T, B, and NK lymphocyte lineages.

MingCeler Biotechnology successfully generated the nuNPG strain (NOD-Prkdtm1Ming Il2rgtm1Ming/MC) in 2023 via homologous recombination, resulting in complete KO mutations of both Prkdc and IL2rg. The nuNPG mice have an inbred genetic background with homozygous Prkdctm1Ming and IL2rgtm1Ming mutations. The phenotype of nuNPG mice has been validated according to the MINGCELER GENETIC POLICY.