Observation of the dynamic changes in the urinary proteome in rats during immunization

Objective Changes in the immune system in the urine proteome were observed by injecting bovine serum albumin and aluminum hydroxide adjuvant into rats. Methods In this study, bovine serum albumin and aluminum hydroxide adjuvant were injected into rat thigh muscle, urine was collected, differential proteins were identified by liquid chromatography—mass spectrometry (LC—MSMS/MS), and biological pathways of differential proteins were analyzed by IPA software to observe the changes in the immune system as evidenced by rat urinary proteins. Results Fifteen rats were intramuscularly injected with normal saline, aluminum hydroxide adjuvant, bovine serum albumin, aluminum hydroxide adjuvant, and bovine serum albumin (BSA) mixture to construct the models of the control, adjuvant, BSA, and mixed groups. Upon comparing the different proteins between different groups to obtain the relevant biological pathways, it was found that adjuvants can be observed in urine to help bovine serum albumin stimulate the immune system to respond earlier. It was also observed in urine that the mixed group successively stimulated immune-related pathways, such as the inflammatory response, T-cell activation, antigen-presenting cell-related pathways, and B-cell-related pathways. Discussion We can observe changes in the immune system from the urine proteome in the early stage, providing some new clues and a basis for future research on the immune system and accelerating vaccine research and development.