1.Preparation of a monoclonal antibody against Trichinella spiralis adult and its protective immunity
Xin GAO ; Xinping ZHU ; Minjun HUANG
Chinese Journal of Infectious Diseases 2001;0(05):-
Objective To prepare a monoclonal antibody(McAb) against Trichinella spiralis (T.s) adult and study its protective immunity. Methods BALB/c mice were immunized with soluble antigens of 3 day adult of T.s. Immnuized spleen cells of BALB/c mice were fused with myeloma cells sp2/0. The hybridoma culture supernatant was isotyped by the Ouchterlony double diffusion technique and the specificity of the McAb was determined by immunoblotting. The protective immunity of the McAb was detected after challenging the mice by the intravenous way. Results A McAb against T.s adult was obtained. The titer of culture fluid and ascetic fluid was 1∶6 400 and 1∶204 800, respectively. This McAb was identified as IgM. Western blotting results showed this McAb can be used to identify 40 000 protein of adult worm, muscle larvae and newborn larvae of T.s. No cross reactions with antigens of Ascaris suum Goeze, Taenia solium Linnaeus, Echinococcus granulosus and Schistosoma were oberserved. The number of muscle larvae was decreased by 55.63% when giving McAb to mice intravenously. Conclusions A species specific McAb against T.s adult was established and its protective immunity was identified. This McAb can be used as a powerful tool in screening Trichinella vaccine candidates.
2.Characterization of immunologic and adhesive abilities of Mycoplasma pneumoniae P1 protein segment
Cuiming ZHU ; Shiping WANG ; Yimou WU ; Shunli GAO ; Minjun YU ; Xi CHEN
Chinese Journal of Microbiology and Immunology 2012;32(8):706-710
Objective To determine the immunogenic and adhesive abilities of a segment (P1C protein) that located at the carboxy terminal region of P1 protein (1125 to 1395 amino acids).Methods A recombinant prokaryotic vector (pGEX6p-2/p1c) was constructed for P1C protein expression in E.coli BL21DE3.The expressed target recombinant protein (rP1C) was identified using SDS-PAGE and Western blot assay,and then extracted by GST-based affinity chromatography.The purified rP1C was used to immunize BALB/c mice to obtain rP1C-antiserum and titer of the antiserum was determined by ELISA.Immunoreactivity of the rP1C to the sera form M.pneumoniae-infected patients was detected using Western blot assay,while activity of the rP1C adhering to HeLa cells as well as adhesion blockage of the rP1C antiserum were detected using indirect immunofluorescence assays.Results The constructed prokaryotic expression system could efficiently express soluble rP1C with a relative molecular weight of 66×103.The antiserum from rP1Cimmunized mice showed an ELISA titer as high as 1:64 000.Both the M.pneumoniae-infected patients' sera and the mouse antiserum against rP1C could recognize as well as combine with the rP1C.rP1C could adhere to HeLa cells and the adhesion could be blocked by the mouse antiserum with an antiserum concentration-dependent manner.Conclusion P1C,a segment of M.pneumoniae P1 protein,possesses powerful immunogenicity and immunoreactivity and cell-adhered activity,indicating the protein segment can be used as an antigen candidate for developing vaccines and serological diagnostic methods of M.pneumoniae-induced diseases.
3.Immune regulation of IL-10 to Schistosoma japonicum infection in p47 GTPase deficient mouse model
Jingjiao WU ; Fang TIAN ; Yanan GAO ; Xiaotang DU ; Meijuan ZHANG ; Minjun JI ; Guanling WU
Chinese Journal of Schistosomiasis Control 2010;22(2):111-116,封3
Objective To investigate the immune response of IL-10 to Schistosoma japonicum infection in the early infectioin model and SEA immunization model of the IGTP~(-/-) and IRG-47~(-/-) mice.Methods In the early infection model,the IGTP knock out (IGTP~(-/-)) mice,IRG-47 knock out (IRG-47~(-/-)) mice and wild-type (WT) C57BL/6J mice were exposed to 300 S.japonicum cercariae via the pinna and sacrificed on day 7 post-infection.Each mouse pinna section was stained with hematoxylin-eosin (HE) to detect the pathological lesions,and the culture supernatant of pinna was used to test the levels of Th1/Th2 cytokines by indirect ELISA.In the SEA immunization model,IGTP~(-/-) IRG-47~(-/-) and WT mice were immunized with SEA twice and sacrificed in 3 weeks after the initial immunization.SEA-specific IgG antibody in sera was detected by indirect ELISA;the levels of Th1/Th2 cytokines were tested in culture supernatant of splenocytes by indirect ELISA;the proportions of CD4~+ T cells,CD8~+ T cells,B cells,Th1 and Th2 cells in the spleen were assayed by FACS.Results Although no obvious differences on the pathology of pinna were observed among the three mouse groups,the level of IL-10 in the culture supernatant of pinna of IRG-47~(-/-) mice was lower than that of IGTP~(-/-) mice in 7 days after the exposure.Following SEA immunization,the level of SEA-specific IgG antibody in sera of IGTP~(-/-) mice was lower than that in WT mice,the level of IL-10 in the culture supernatant of splenocytes of IRG-47~(-/-) mice was higher than that of IGTP~(-/-) and WT mice with the stimulation of SEA.However,the proportion of Th2 cells in the spleen of IRG47~(-/-) mice was the lowest among the three mouse groups.Conclusions SEA is the stimulus of IRG-47 deficiency mice to defend Schistosoma japanicum infection and promote the host to produce a protective response,and IL-10 may play an important role in immune regulation in this process.
4.Erythromycin Molecularly Imprinted Two-dimensional Photonic Crystal Hydrogel Sensor
Minjun GAO ; Genqi LIU ; Yafeng XUE ; Xiaojuan CHEN ; Weijiang SHI ; Xiaodong FAN
Chinese Journal of Analytical Chemistry 2017;45(5):727-733
A molecularly imprinted two-dimensional photonic crystal hydrogel sensor was developed with erythromycin as imprinted molecule, polystyrene two-dimensional photonic crystal as templates, methanol as solvent, methacrylic acid as monomers and ethylene glycol dimethylacrylate as cross-linkers.The imprinted molecule was removed by methanol/acetic acid (9∶1, V/V).The results showed that the diameter of Debye ring increased 6 mm when the concentration of EM changed from 0 to 1×10-6 mol/L.Namely the lattice spacing decreased 30 nm.In addition, the diameter of Debye ring only increased 1.5 and 2.0 mm when the hydrogel immersed in 1×10-6 mol/L roxithromycin (RM) or erythromycin ethylsuccinate (EEs) solution.The result indicated that the sensor had high selectivity and could be used in determination of erythromycin with low cost and easy operation.
5.Nanopolyphenol rejuvenates microglial surveillance of multiple misfolded proteins through metabolic reprogramming.
Dayuan WANG ; Xiao GU ; Xinyi MA ; Jun CHEN ; Qizhi ZHANG ; Zhihua YU ; Juan LI ; Meng HU ; Xiaofang TAN ; Yuyun TANG ; Jianrong XU ; Minjun XU ; Qingxiang SONG ; Huahua SONG ; Gan JIANG ; Zaiming TANG ; Xiaoling GAO ; Hongzhuan CHEN
Acta Pharmaceutica Sinica B 2023;13(2):834-851
Microglial surveillance plays an essential role in clearing misfolded proteins such as amyloid-beta, tau, and α-synuclein aggregates in neurodegenerative diseases. However, due to the complex structure and ambiguous pathogenic species of the misfolded proteins, a universal approach to remove the misfolded proteins remains unavailable. Here, we found that a polyphenol, α-mangostin, reprogrammed metabolism in the disease-associated microglia through shifting glycolysis to oxidative phosphorylation, which holistically rejuvenated microglial surveillance capacity to enhance microglial phagocytosis and autophagy-mediated degradation of multiple misfolded proteins. Nanoformulation of α-mangostin efficiently delivered α-mangostin to microglia, relieved the reactive status and rejuvenated the misfolded-proteins clearance capacity of microglia, which thus impressively relieved the neuropathological changes in both Alzheimer's disease and Parkinson's disease model mice. These findings provide direct evidences for the concept of rejuvenating microglial surveillance of multiple misfolded proteins through metabolic reprogramming, and demonstrate nanoformulated α-mangostin as a potential and universal therapy against neurodegenerative diseases.