In addition, IL-10 augments proliferation and differentiation of B cells. Intestinal histopathology in Il10 tm1Cgn mice shares some features with human Crohn's disease. The duodenum, proximal jejunum, cecum, and proximal colon are most severely affected. The inflammatory process is characterized by focal transmural inflammation, mucosal proliferation, focal ulceration, and extensive infiltration with lymphocytes, plasma cells, macrophages, and scattered neutrophils.
Environmental factors play an important role in the severity of inflammation as well.
The overlying epithelium was eroded, suggesting that these mild lesions were traumatic rather than associated with the mutation. Thirteen mice, ranging from 3 to 22 months of age, were examined histologically. Lesions varied in severity among individuals and progressed with age. The Il10 tm1Cgn mutation is maintained under barrier conditions by The Jackson Laboratory Mouse Mutant Resource. Both strains are maintained by mating homozygous siblings.