1.Development and identification of mouse anti-human S100 A9 natural protein
Danyang MI ; Rui DUAN ; Junying SONG ; Xiangdong SUN ; Zhongyun ZHANG ; Min YAN ; Yong YUAN ; Zhenqiang ZHANG ; Gaiping ZHANG ; Wendi LIU
Chinese Journal of Immunology 2016;32(10):1485-1490
Objective:To prepare and identify the mouse anti-human monoclonal antibodies ( mAbs) using leukocytes as im-munogens. Methods: The mice were immunized using human peripheral blood leukocytes. Then, use of B lymphocyte hybridoma technology preparation of mAbs,followed screening by immunocytochemistry and limited dilution. The secreted mAbs were identified by immunoprecipitation,mass spectrometry,Western blot,ELISA and immunohistochemistry. Results:The 35 positive polyclonal cells were obtained,of which 11 strains secreted mAbs against S100A9. And one strain was used to prepare monoclonal antibody. The purified mAb against S100A9 were purified and identified as IgG1 subtype,with the titer,purity and affinity constant was 1∶3. 18×105,95% and 3. 54×108 L/mol,respectively. This mAb generally had 0. 12% crossed reactivity to S100A8 ,and showed little or no cross reactivity to S100A12 and S100A13. The prepared monoclonal antibodies can specifically recognizes the S100A9 antigen in human breast cancer tissues. Conclusion:Successful preparation of mAb against S100A9,which can secrete specific mAb against S100A9 protein with high titers and specificity have been established successfully,which laid the foundation for the immunology application.
2.Double-edged Sword Role of Iron-loaded Ferritin in Extracellular Vesicles
Shinya TOYOKUNI ; Yingyi KONG ; Hao ZHENG ; Danyang MI ; Misako KATABUCHI ; Yashiro MOTOOKA ; Fumiya ITO
Journal of Cancer Prevention 2021;26(4):244-249
Human epidemiological and animal studies have demonstrated that excess iron is a risk for cancer. The responsible mechanisms are: 1) increased intracellular iron catalyzes the Fenton reaction to generate hydroxyl radicals, leading to mutagenic oxidative DNA lesions; 2) iron is necessary for cellular proliferation as cofactors of many enzymes. Thus, iron-excess milieu promotes selecting cellular evolution to ferroptosis-resistance, a major basis for carcinogenesis. Ferritin is a 24-subunit nanocage protein required for iron storage under the regulation of the iron-regulatory protein (IRP)/iron-responsive element (IRE) system. Ferritin is a serum marker, representing total body iron storage. However, how ferritin is secreted extracellularly has been unelucidated. We recently discovered that an exosomal marker CD63 is regulated by the IRP/IRE system and that iron-loaded ferritin is secreted as extracellular vesicles under the guidance of nuclear receptor coactivator 4 (NCOA4). On the other hand, we found that macrophages under asbestos-induced ferroptosis emit ferroptosis-dependent extracellular vesicles (FedEVs), which are received by nearby mesothelial cells, resulting in significant mutagenic DNA damage. Therefore, cells, including macrophages, can share excess iron with other cells, via iron-loaded ferritin packaged in extracellular vesicles as safe non-catalytic iron. However, similar process, such as one involving FedEVs, may cause accumulation of excess iron in other specific cells, which may eventually promote carcinogenesis.
3.Establishment and evaluation of a dual fluorescent RT-LAMP assay for PEDV and TGEV detection
Ran ZANG ; Feifei XU ; Danyang ZHENG ; Zhiqian ZHAO ; Mi ZHAO ; Hui WANG ; Jie GAO ; Yang MU
Chinese Journal of Veterinary Science 2024;44(8):1600-1610
To develop a rapid differential detection method for porcine epidemic diarrhea virus(PEDV)and transmissible gastroenteritis virus(PEDV),M gene sequences of PEDV and TGEV were compared,the inner and outer primer pairs and probes were designed according to the highly conserved region.PEDV-Probe was labeled with FAM at5'end and BHQ1 at 3'end.TGEV-Probe was labeled with CY5.5 at the 5'end and BHQ2 at the 3'end.After optimizing the reaction condi-tions and system,a dual fluorescent RT-LAMP assay for PEDV and TGEV rapid identification was established.The amplification could be completed within 60 min in a 63 ℃ water bath and then stopped at 85 ℃ for 10 min.Then the tubes were placed in a multicolor imaging system,and the re-sults could be observed under 520 nm and 690 nm dual channels.There was no cross-reaction when other common swine viral pathogens were detected by this method.The sensitivity of the assay was evaluated with a 10-fold diluted recombinant plasmid as templates.The lowest detection limit was 102 copies/μL recombinant plasmid,which was 10 times more sensitive than the conventional RT-PCR method.Seventy-two PEDV-positive samples,49 TGEV-positive samples,and 40 PEDV and TGEV co-infected samples were detected from 175 anal swab samples of diarrheic piglets by the established method,which were all higher than the detection rates of the conventional RT-PCR method.The dual fluorescent RT-LAMP method established in this study can be used to amplify the target gene in an ordinary water bath without gel electrophoresis,which provides technical sup-port for rapid and convenient differential diagnosis of PED and TGE and simultaneous detection of PEDV and TGEV co-infection.