1.Rapid identification of four common bacteria by SELDI-TOF MS protein fingerprints
Daiwen XIAO ; Yongchang YANG ; Hua LIU ; Hua YU ; Chunbao XIE ; Hangfeng ZHANG ; Wenfang HUANG
Chinese Journal of Microbiology and Immunology 2012;32(6):566-570
Objective To establish protein fingerprints of common bacteria in clinics and to lay a foundation for rapid identification of bacteria.Methods Strains of Escherichia coli,Klebsiella pneumoniae,Pseudomonas aeruginosa and Staphylococcus aureus were detected by surface enhanced laser desorption and ionization time-of-flight mass spectrometry (SELDI-TOF MS).Stable expression protein peaks were screened and the data was input into the self-constructed Fingerwave software for identification of target bacteria by protein fingerprint comparison.Two hundred and fifty-six clinical isolates,including E.coli,K.pneumoniae,P.aeruginosa and S.aureus were detected and the data was compared with constructed database to evaluate its diagnostic value.Results The protein fingerprints including four common bacteia was used to identify the target bacteria with identification rate of 93.1% (54/58) for E.coli,87.2% (75/86) for K.pneumoniae,96.2% (60/63) for P.aeruginosa and 96.2% (51/53) for S.aureus,respectively.Conclusion Common bacteria can be rapidly identified by using the protein fingerprint comparison,which provides a powerful tool for bacterial identification.
2.Analysis of VSIG4 expression in clear cell renal cell carcinoma and its correlation with tumor infiltrating immune cells
Hangfeng LIU ; Shenglu LIU ; Lianrui DUAN ; Likun ZAN ; Yanjie MA ; Lijun YANG
Chinese Journal of Immunology 2024;40(5):918-924
Objective:To explore expression of VSIG4 in clear cell renal cell carcinoma(ccRCC)and its correlation with immune cells infiltration and prognosis.Methods:RNA-seq data of ccRCC and corresponding clinical data of patients were downloaded from The Cancer Genome Atlas(TCGA)database.Wilcoxon rank-sum test was used to analyze VSIG4 mRNA expression in ccRCC and normal renal tissues.Correlation between VSIG4 expression and clinicopathological parameters was analyzed by Wilcoxon rank-sum or Kruskal-Wallis rank-sum test.Kaplan-Meier method was used to analyze the correlation between VSIG4 expression and progno-sis of patients.Gene set enrichment analysis(GSEA)was used to explore the signaling pathway of VSIG4 in ccRCC.Correlation between VSIG4 level and tumor infiltrating immune cells was analyzed via CIBERSORT in R software.Western blotting was used to detect VSIG4 protein level in human renal epithelial cell line 293T,and human renal carcinoma cell line ACHN,A498,786-O and OS-RC-2.Results:Expression level of VSIG4 in ccRCC was significantly higher than that in normal tissues(P<0.05).VSIG4 expression was significantly correlated with the stages of distant metastasis and lymph node metastasis(P<0.05).Overall survival rate of patients with high VSIG4 expression was significantly lower than that of patients with low expression(P<0.05).GSEA enrichment analysis showed that VSIG4 was mainly enriched in apoptosis,chemokine signaling pathway,cell adhesion molecules and other signaling path-ways.VSIG4 expression was negatively correlated with M1 macrophages(r<0,P<0.05),while positively correlated with M2 macro-phages(r>0,P<0.05).Western blotting results showed that expression of VSIG4 in renal cell carcinoma cells was higher than that in normal renal cells.Conclusion:VSIG4 is highly expressed in ccRCC,and is negatively associated with prognosis,which may become a prognostic biomarker for ccRCC patients.
3.Proteomic analysis of radiation-induced esophagitis in rats
Yuehua ZHANG ; Hangfeng LIU ; Shuyu ZHANG ; Mengjie DU ; Xiaochen MENG ; Wenling TU
Chinese Journal of Radiological Medicine and Protection 2024;44(9):725-733
Objective:To investigate the impacts of ionizing radiation on protein expression profiles in esophageal tissues of rats using quantitative proteomics, in order to reveal the molecular mechanisms underlying the onset and development of radiation-induced esophagitis (RIE).Methods:A total of twenty-four male SD rats were divided by simple randomization into three groups: the control, 25 Gy irradiation, and 35 Gy irradiation groups, and their esophageal tissues were collected at 7 d post-irradiation to extract total protein. Then, changes in the protein expression profiles of the esophageal tissues in irradiated rats were investigated using tandem mass tag (TMT)-labeled quantitative proteomics and bioinformatics analysis. Additionally, the expressions of two key proteins, Hp and Ndufs4, were validated using immunohistochemistry and Western blot.Results:A comparison with the control group revealed a total of 847 differentially expressed proteins (DEPs; 483 up-regulated and 364 down-regulated) following 25 Gy irradiation and 699 DEPs (443 up-regulated and 256 down-regulated) following 35 Gy irradiation. Different radiation doses led to common 326 up-regulated proteins, which were mainly involved in biological processes and signaling pathways related to immune and inflammatory responses, and 210 down-regulated proteins, which were primarily involved in biological processes and signaling pathways related to energy production and metabolism. Furthermore, a total of 155 proteins were screened using a constructed protein protein interaction(PPI) network. Of these proteins, the up-regulated ones were most associated with three functional pathways, namely innate immune responses, complement and coagulation cascades, and innate immune system, while the down-regulated ones were most associated with energy acquisition via oxidizing organic compounds, oxidative phosphorylation, and the tricarboxylic acid (TCA) cycle and respiratory electron transfer. These functions were enriched with nine complement-related up-regulated and five mitochondria-related down-regulated proteins, respectively. Ionizing radiation significantly up-regulated Hp ( t = 27.94, 10.96, P<0.001) and down-regulated Ndufs4 ( t = 59.27, 54.07, P<0.001), consistent with the protein sequencing result. Conclusions:Ionizing radiation can change the protein expression profiles in the esophageal tissues of rats, and these DEPs are involved in multiple radiobiology-related functional pathways such as immune processes, inflammatory responses, and abnormal energy metabolism. Screening and validation of key proteins are helpful for identifying potential biomarkers of radiation-induced esophagitis.