Crbn-I391V

Fig.1 Detection of Crbn expression in bladder and cerebellum by RT-PCR. Bladder and cerebellum RNA was extracted from 8-week-old male wild-type C57BL/6 (WT)(n=2) and homozygous Crbn-I391V knockin mice (HO) (n=6), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mRNA primers. 

Abbr. M, marker; HO, homozygous; WT, wild type.

Fig.2 mRNA sequencing of Crbn-I391V knockin mice. 

Abbr. HO, homozygous; WT, wild type.

Fig.3 The degradation of GSPT1, IKZF3 and CK1a by CC-885 in CRBN-I391V mice in vivo.

The spleen, skeletal muscle and heart were collected from 8-week-old male homozygous CRBN-I391V mice, and then analyzed by western blot with anti-GSPT1 antibody, anti-IKZF3 antibody and anti-CK1a antibody. 

Fig.4 In vivo hepatotoxicity evaluation of CC-885 in Crbn-I391V mice.

Serum biochemistry was analyzed 6 h post-treatment with vehicle or CC-885 (5 mg/kg) in 8-week-old male homozygous Crbn-I391V mice.

Fig.5 CRBN modulators can induce IL-2 secretion and Aiolos degradation in mice with the Crbn-I391V point mutation. 

(A) ELISA analysis of IL-2 expression levels in CD4-positive T cells from Crbn-I391V point mutation mice. The results showed that following treatment with 5,000 nM lenalidomide and 5,000 nM pomalidomide, IL-2 expression levels in CD4-positive T cells from Crbn-I391V point mutation mice increased significantly. (B) Flow cytometry analysis of Aiolos expression levels in the spleens of Crbn-I391V mutant mice. The results showed that following treatment with 10 µM lenalidomide and 2 µM pomalidomide, Aiolos expression levels in CD19-positive B cells and CD3-positive T cells in the spleens of Crbn-I391V mutant mice decreased significantly. (Data provided by collaborators)

The above results demonstrate that the Crbn-I391V point mutation mouse model can be utilised for the in vivo study of the toxicity and efficacy of CRBN-targeting drugs.