Conclusion
The difference between the results of one group and those of the other suggest that after the 5th LPS injection, multiple low doses of LPS activated splenocytes and restored the number of splenocytes, which maintained and possibly enhanced the regulation of the immune function of the spleen.
Material and methods
Forty-eight 28-day-old piglets were divided into two groups: the LPS group and the control group. During the experimental period of thirteen days, the LPS group was intraperitoneally injected with LPS (100 μg/kg) once per day, and the control group was injected with the same volume of 0.9% sterile saline. On the 1st, 5th, 9th and 13th days, the piglets' spleens were collected for isolating splenocytes. The proliferation ability of splenocytes was evaluated by the cell-counting-kit 8 method. Flow cytometry was used to detect cell cycle stage and apoptosis, and the nitric oxide level of cell supernatant was also tested.
Methods
Forty-eight 28-day-old piglets were divided into two groups: the LPS group and the control group. During the experimental period of thirteen days, the LPS group was intraperitoneally injected with LPS (100 μg/kg) once per day, and the control group was injected with the same volume of 0.9% sterile saline. On the 1st, 5th, 9th and 13th days, the piglets' spleens were collected for isolating splenocytes. The proliferation ability of splenocytes was evaluated by the cell-counting-kit 8 method. Flow cytometry was used to detect cell cycle stage and apoptosis, and the nitric oxide level of cell supernatant was also tested.
Results
In the experimental group, the proliferation ability of splenocytes was enhanced, the proportion of cells in the G0/G1 phase was smaller, and cells were promoted to the S and G2/M phases. Meanwhile, apoptosis was suppressed and nitric oxide release upregulated. The results were significantly different between the LPS group and the control group on the 5th and 9th days.