h4-1BB

Figure 1. Expression of humanized 4-1BB in the activated spleen lymphocytes of heterozygous humanized 4-1BB mice is detected by FACS. 

The spleen lymphocytes of heterozygous humanized 4-1BB mice were activated by anti-CD3 and anti-CD28 for 48 hours, and then collected for staining. Along with a group undergoing no stimulation, the expression of humanized 4-1BB was detected by FACS.The results showed that the active expression of humanized 4-1BB can be detected in both activated CD8– and CD8+ T lymphocytes collected from heterozygous humanized 4-1BB mice.

Figure 2. Expression of humanized 4-1BB in the activated spleen lymphocytes of homozygous humanized 4-1BB mice is detected by FACS. 

The spleen lymphocytes of homozygous  humanized 4-1BB mice were activated by anti-CD3 and anti-CD28 for 72 hours, and then collected for staining. The expression of humanized 4-1BB was detected by FACS. The results showed that the active expression of humanized 4-1BB can be detected in both activated CD4+ and CD8+ T lymphocytes collected from homozygous humanized 4-1BB mice.

Figure 3. In vivo validation in a MC38 tumor-bearing model of humanized 4-1BB mice. 

Humanized 4-1BB mice were inoculated with MC38 colon cancer cells. After the tumors grew to 100 mm3, the animals were randomly assigned into different groups (n=8). The drug was given twice a week for a total of 4 administrations. The results showed that drug targeting human 4-1BB, exerted a significant anti-tumor effect (p<0.05), demonstrating that the humanized 4-1BB mice are a good in vivo model for validating the efficacy of antibodies targeting human 4-1BB.