Objective:To observe the presence or absence of necroptosis in PC12 cells after radiation injury, and to detect the expression of receptor-interacting protein 3(RIP3) and evaluate its regulatory effect on necroptosis.Methods:PC12 cells were treated with different doses of irradiation and their necroptosis was detected by lactate dehydrogenase (LDH) release at different time points. After pretreatment with necroptosis inhibitor Necrostatin-1(Nec-1), the changes of cell necroptosis were detected by LDH. The expression level of RIP3 after irradiation intervention was detected by Western blot (WB). After pretreatment with the RIP3-specific inhibitor GSK′872, the changes of cell necroptosis were detected by LDH. The best transfection sequence of RIP3 knockout was screened by WB. The cells were divided into the control group, irradiation group, solvent control group, no-load control group and pretreatment group. WB, immunofluorescence staining, MTT, LDH and Annex V-fluorescein Isothiocyanate/Propidium Iodide (AnnexV-FITC/PI) flow cytometry were used for detection and analysis.Results:After 4 Gy irradiation, the degree of cell necrosis was the highest after 3 hours of culture, and the expression level of RIP3 protein was up-regulated. The cell necrosis was decreased after Nec-1, GSK′872 and RIP3 gene knockdown pretreatment.Conclusions:The radiation injury of 4 Gy can induce the necroptosis of PC12 cells, and the most significant effect can be observed when cultured for 3 hours after irradiation. RIP3 is involved in the process of necroptosis of PC12 cells induced by radiation injury, and plays a pivotal positive regulatory role.

Although the development of COVID-19 vaccines has been a remarkable success, the heterogeneous individual antibody generation and decline over time are unknown and still hard to predict. In this study, blood samples were collected from 163 participants who next received two doses of an inactivated COVID-19 vaccine (CoronaVac®) at a 28-day interval. Using TMT-based proteomics, we identified 1,715 serum and 7,342 peripheral blood mononuclear cells (PBMCs) proteins. We proposed two sets of potential biomarkers (seven from serum, five from PBMCs) at baseline using machine learning, and predicted the individual seropositivity 57 days after vaccination (AUC = 0.87). Based on the four PBMC's potential biomarkers, we predicted the antibody persistence until 180 days after vaccination (AUC = 0.79). Our data highlighted characteristic hematological host responses, including altered lymphocyte migration regulation, neutrophil degranulation, and humoral immune response. This study proposed potential blood-derived protein biomarkers before vaccination for predicting heterogeneous antibody generation and decline after COVID-19 vaccination, shedding light on immunization mechanisms and individual booster shot planning.
Humans ; COVID-19 Vaccines ; Leukocytes, Mononuclear ; Proteomics ; COVID-19/prevention & control* ; Vaccination ; Antibodies ; Antibodies, Viral ; Antibodies, Neutralizing