Catalog Number: C001527
Strain Name: BALB/cAnCya-Il10em1/Cya
Genetic Background: BALB/cAnCya
Reproduction: Homozygote x Homozygote
Interleukin-10 (IL-10) is a cytokine secreted by activated T cells, monocytes, B cells, and macrophages, among other antigen-presenting cells. It exhibits broad biological activity. In immune regulation and inflammatory responses, IL-10 can reduce the expression of Th1 cytokines, MHC-II antigens, or co-stimulatory molecules. Simultaneously, it enhances B cell survival, proliferation, and antibody production. Both overexpression (as seen in systemic lupus erythematosus and tuberculosis) and deficiency (as observed in inflammatory bowel disease, psoriasis, asthma, and rheumatoid arthritis) of IL-10 have pathological and physiological significance. IL-10 is a critical susceptibility gene for inflammatory bowel disease (IBD), and its functional defects play a central role in the development of ulcerative colitis (UC)-type IBD [1]. The genetic polymorphism of IL-10 may also contribute to the occurrence of UC-type IBD or Crohn’s disease (CD)-type IBD [2]. Therefore, IL-10 gene knockout mice exhibit a phenotype similar to human inflammatory bowel disease (IBD) and are widely used in research related to relevant diseases [3].
During the gene editing process, using different mouse strain backgrounds may lead to differences in disease phenotypes. BALB/c strain and C57BL/6 strain exhibit significant differences in susceptibility to infection, resistance, and immune deficiencies. For specific applications such as evaluating antifungal drug efficacy, cancer treatment, and immunological research, the BALB/c strain has its unique advantages [4-6]. Research has found that IL-10-deficient BALB/c mice are more susceptible to colitis than mice of the C57BL/6 strain. Additionally, the disease phenotype is more severe in IL-10-deficient BALB/c mice, making them a more effective model for simulating the disease progression of human colitis [7].
This model is Il10 gene knockout mice, where the Il10 gene homologous to the human IL10 gene has been knocked out in BALB/cAnCya mice. Homozygous BALB/c-Il10 KO mice are viable and fertile. At 8 to 9 weeks of age, BALB/c-Il10 KO mice spontaneously develop symptoms of colitis, characterized by weight loss, reduced survival rates, elevated levels of inflammatory factors, and abnormalities in intestinal inflammation and phenotype. BALB/c-Il10 KO mice can be used for research related to Crohn’s disease (CD), colitis, other inflammatory bowel diseases (IBD), cancer, congenital and adaptive immune disorders, as well as various inflammation or autoimmune conditions. It should be noted that due to individual variability and environmental factors, the disease presentation of this model may vary. The data in this manual are based on internal facility observations and are provided for reference. Actual disease presentation may vary; please use the mice according to your specific experimental conditions for best results.
The Il10 gene is located on mouse chromosome 1 and exons 1-5 were knocked out by gene editing techniques.
Figure 1. Survival status of BALB/c-Il10 KO mice (IL10 KO) and wild-type mice (WT). The results indicate that homozygous BALB/c-Il10 KO mice have a reduced body weight compared to wild-type mice. In comparison to wild-type mice, homozygous BALB/c-Il10 KO mice begin experiencing mortality from the 10th week, with male mice reaching a 50% mortality rate by the 25th week, while the disease progression in female mice is slower, with a mortality rate of approximately 20% by the 25th week.
Figure 2. Incidence and Disease Score in BALB/c-Il10 KO mice (IL10 KO) and wild-type mice (WT). Based on the Disease Activity Index (DAI) and Crohn’s Disease Activity Index (CDAI), a quantitative analysis was performed on the disease incidence in homozygous BALB/c-Il10 KO mice. The results indicate that homozygous BALB/c-Il10 KO mice begin to exhibit symptoms from 8 to 9 weeks of age. Male mice experience disease onset earlier than female mice, and the severity of the disease progressively worsens with age.
*The referenced symptoms are wrinkled fur/soft stools. Additionally, the disease progression in mice may vary under different environmental conditions, and some mice have been observed to self-heal.
Figure 3. Clinical appearance and body condition of 22-week-old male BALB/c-Il10 KO mice. By observing the external appearance of the mice, it is evident that male homozygous BALB/c-Il10 KO mice exhibit severe colitis phenotypes at 22 weeks of age. These mice display symptoms such as diarrhea, blood in the stool, rectal prolapse, and abnormal body posture.
Figure 4. Anatomical observations of the colon in BALB/c-Il10 KO mice and wild-type mice (WT). The results indicate that the colorectal intestinal wall of male homozygous BALB/c-Il10 KO mice thickens, the intestines become thicker, the color becomes ruddy, and inflammation occurs. Additionally, the intestinal contents are viscous and diffuse, and the stool shape is irregular. Furthermore, the onset of the disease is earlier in male mice than in female mice, and the severity of the condition is greater.
Figure 5. H&E staining of the colon in BALB/c-Il10 KO mice and wild-type mice (WT). The results reveal that in the early stages of the disease (10 weeks), the colon tissues of male homozygous BALB/c-Il10 KO mice exhibit inflammatory cell aggregation and crypt damage. As the disease progresses to the late stage (22 weeks), the disease phenotype worsens, and even goblet cell loss becomes evident.
Figure 6. Expression levels of inflammatory factors in the colon of BALB/c-Il10 KO mice and wild-type mice (WT). RT-qPCR results reveal that, compared to wild-type mice and non-onset homozygous BALB/c-Il10 KO mice, the expression levels of TNF-α and IL6 are significantly elevated in homozygous BALB/c-Il10 KO mice that have already developed the disease.
References
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