ObjectiveTo establish paraquat (PQ)-induced acute respiratory distress syndrome (ARDS) mice model via gavage, in order to simulate oral adminitration in clinical situations.MethodsSeventy-eight 6-8-week-old, specific pathogen free female C57 mice were chosen in this study. The mice were randomly divided into the control group (n=6) and the PQ model group(n=36); the mice in the latter group were randomly divided into 6 poisoning model subgroups further, with 6 mice in each, to find out the suitable concentration of PQ to establish stable ARDS model. The mice in the control group were given phosphatebuffer saline (PBS) by gavage, 200 μL per mouse; while the mice in the 6 poisoning model subgroups were given PQ with varies doses of 3, 10, 30, 100, 150, 300 mg/kg respectively by gavage. The clinical manifestations were observed for 7 days, and the ratio of lung wet/dry (W/D) was measured. After the suitable concentration of PQ for stable ARDS mice model was found, the other 36 mice were randomly divided into the controlgroup and the poisoning model group, both were divided into 4 subgroups, according to different observation point in time (1 day and 2, 3, 4 days after PQ gavage). The mice in the 4 control subgroups (n=3) were given PBS by gavage, 200 μL per mouse; while the mice in the 4 poisoning model subgroups (n=6) were given PQ with the suitable concentration for ARDS mice model by gavage. Pathological manifestations by Haematoxylin-Eosin staining and lung injury score were observed and analyzed.ResultsThe mice began to die at the PQ dosage of 150 mg/kg; while the death rate was stable at 300 mg/kg. On the 2nd and 4th day after PQ gavage, lung W/D was 5.335, 6.113, and 5.525, and 6.403, respectively in the mice in 150 and 300 mg/kg subgroup, which differed much from those in the control group (P<0.001). Congestion, edema, hemorrhage, alveolar structure damage, inflammation cells infiltration of lung tissue were observed, and lung injury score increased.ConclusionPQ-induced ARDS mice model by gavage is established successfully.
ObjectiveTo investigate the feasibility of small molecule compound XAV939 to induce mouse embryonic stem cells (mESC) to differentiate into cardiac myocytes. MethodsWe revived and cultured undifferentiated mESC growing confluently on trophoderm made of mouse embryonic inoblast cell. The mESCs were digested by trypsin to form embryoid bodies (EBs) by handing drop method. After plated, EBs were induced by XAV939 to differentiate into cardiac myocytes. We observed the cardiac myocytes with lightmicroscopy and identified it with immunofluorescence method. Result The XAV939 can effectively induce mESC into cardiac myocytes with the mean efficiency rate of 71.85%±1.05%. The differentiated cardiac myocytes shrinked spanteously and rhythmicly. The cardiac troponin T as the special marker of cardiac myocyte was positive. ConclusionThe small molecule compound XAV939 could effectively induce mES cells into cardiac myocytes.
ObjectiveTo investigate the co-transplantation of C57-green fluorescent protein (GFP) mouse epidermis and dermis cells subcutaneously to induce the hair follicle regeneration. MethodC57-GFP mouse epidermis and dermis were harvested for isolation the mouse epidermis and dermis cells. The morphology of epidermis and dermis mixed cells at ratio of 1:1 of adult mouse, dermis cells of adult mouse, cultured 3rd generation dermis cells were observed by fluorescence microscope. Immunocytochemistry staining was used to detect hair follicle stem cells markers in cultured 3rd generation dermis cells from new born C57-GFP mouse. And then the epidermis and dermis mixed cells of adult mouse (group A), dermis cells of adult mouse (group B), cultured 3rd generation dermis cells of new born mouse (group C), and saline (group D) were transplanted subcutaneously into Balb/c nude mice. The skin surface of nude mice were observed at 4, 5, 6 weeks of transplantation and hair follicle formation were detected at 6 weeks by immunohistochemistry staining. ResultsThe isolated C57-GFP mouse epidermis and dermis cells strongly expressed the GFP under the fluorescence microscope. Immunocytochemistry staining for hair follicle stem cells markers in cultured 3rd generation dermis cells showed strong expression of Vimentin and α-smooth muscle actin, indicating that the cells were dermal sheath cells; some cells expressed CD133, Versican, and cytokeratin 15. After transplanted for 4-6 weeks, the skin became black at the injection site in group A, indicating new hair follicle formation. However, no color change was observed in groups B, C, and D. Immunohistochemical staining showed that new complete hair follicles structures formed in group A. GFP expression could be only observed in the hair follicle dermal sheath and outer root sheath in group B, and it could also be observed in the hair follicle dermal sheath, outer root sheath, dermal papilla cells, and sweat gland in group C. The expression of GFP was negative in group D. ConclusionsCo-transplantation of mouse epidermis and dermis cells can induce the hair follicle regeneration by means of interaction of each other. And transplantation of isolated dermis cells or cultured dermis cells individually only partly involved in the hair follicles formation.
Objective To investigate the possibility of gene therapy of osteolysis around artificial joint prosthesis by constructing the recombinant adenovirus which can silence tumor necrosis factor α (TNF-α). Methods The primer of small interfering RNA (siRNA) coding sequence of silent TNF-α was designed and amplified, and then RAPAD adenovirus packaging system was used to load the sequence to adenovirus, and the recombinant adenovirus Ad5-TNF-α-siRNA-CMVeGFP which lacked both E1 and E3 regions was constructed. Then 64 female BABL/C mice (weighing, 20-25 g) were randomly divided into 4 groups (n=16): blank control (group A), positive control (group B), simple adenovirus (group C), and treatment group (group D). The prosthetic-model was established in group A, and the prosthetic-loosening-model in groups B, C, and D. At 2 weeks after modeling, PBS solution was injected first, and then the same solution was injected 24 hours later in group A; titanium particle solution was injected, and then PBS solution, Ad5 E1-CMVeGFP (1 × 109 PFU/mL), and Ad5-TNF-α-siRNA-CMVeGFP (1 × 109 PFU/mL) were injected, respectively in groups B, C, and D 24 hours later, every 2 weeks over a 10-week period. The general condition of mice was observed after operation. The tissues were harvested for histological observation, and the expression of TNF-α was detected by Western blot at 12 weeks after operation. Results The positive clones were achieved by enzyme digestion and confirmed by DNA sequencing after loading the target genes into adenovirus vector, and then HEK293 cells were successfully transfected by recombinant adenovirus Ad5-TNF-α-siRNA-CMVeGFP. All mice survived to the completion of the experiment. Histological observation showed that there were few inflammatory cells and osteoclasts in group A, with a good bone formation; there were a large number of inflammatory cells and osteoclasts in groups B and C, with obvious bone destruction; inflammatory cells and osteoclasts in group D was less than those in groups B and C, with no obvious bone destruction. Significant difference was found in the limiting membrane thickness and the number of osteoclasts (group A lt; group D lt; group B lt; group C, P lt; 0.05). Western blot showed that the TNF-α expression levels were 0.235 ± 0.022, 0.561 ± 0.031, 0.731 ± 0.037, and 0.329 ± 0.025 in groups A, B, C, and D respectively, showing significant difference among 4 groups (P lt; 0.05). Conclusion The recombinant adenovirus for silencing TNF-α is successfully constructed, which can effectively inhibit osteolysis by silencing TNF-α expression in the tissues around prosthesis in mice.
Objective Aseptic loosening of prosthesis is associated with peri prosthetical osteolysis caused by osteoclast activation. Receptor activator of nuclear factor kappa B (NF-κB) l igand (RANKL)/receptor activator of NF-κB (RANK) signalpathway is fundamental in osteoclast activation. To determine whether RANKL antibody can inhibit inflammatory osteolysis in a osteolysis model of mouse. Methods Sixty female BALB/c mice (aged 8-10 weeks, weighing 18-20 g) were selected. The skull bone piece was harvested from 20 mice as the donor of bone graft; the subcutaneous air pouches (2 cm × 2 cm) models were established on the back of the other 40 mice and the skull bone piece was inserted into the air pouches. The 40 mice were equally divided into groups A (negative control group), B (positive control group), C (low-dose RANKL antibody group), and D (high-dose RANKL antibody group). At 1 day after bone graft, 0.5 mL PBS was injected into the pouch of group A, 0.5 mL PBS containing titanium particle into groups B, C, and D. At 2 days before the titanium particle was injected, RANKL antibody (0.1 mL) were injected into the pouch of group C (50 μg/mL) and group D (500 μg/mL), respectively every day for 2 days, and 0.1 mL PBS into groups A and B. At 14 days after bone implantation, the pouchmembranes containing implanted bone were harvested for gross observation and histological analyse. Results All mice survived to the end of experiment, and incisions healed well. The gross observation showed that inflammatory responses, exudation, and vascular proliferation were obvious in group B, and were inconspicuous in groups A, C, and D. The histological analysis showed that significantly more infiltration of inflammatory cells, more obvious bone resorption, more bone collagen loss, and more positive staining area were observed in group B than in groups A, C, and D. There were significant differences in inflammatory cell number, pouch membrane thickness, bone collagen loss, and osteoclast content between group B and groups A, C, and D (P lt; 0.05). Conclusion RANKL antibody can directly blockRANKL/RANK signal pathway, which is an efficient therapy to inhibit bone absorption associated with implant wearing particles.
Objective To investigate the expression of micro-dystrophin gene in myoblast cultured in vitro, to explore the possibil ity of combining myoblast transplantation with gene transfer for Duchenne muscular dystrophy therapy. Methods Competent Escherichia coli JM109 was prepared, which transformed with plasmid pSL139, and positive clones were picked to cultivate. Plasmid was extracted with Alkal ine lysis method and cutted with both Pvu I and Cla I enzyme. Agarose gel electrophoresis was employed to take pictures. Ten healthy 5-7 days old male C57/BL10 mice were selected, weighing4-5 g, the primary and subcultured myoblasts were cultured with multi-step enzymatic digestion and differential adhesionmethod, and Desmin immunofluorescent method was used to identfy. The 3rd generation myoblasts that were transfected with plasmid pSL139 mediated by l iposome served as the experimental group, untransfected cells served as the control group. After 48 hours of transfection, the expressions of micro-dystrophin mRNA and protein in myoblasts were detected with RTPCR and cell immunofluorescent methods, and the transfection efficiency was caculated. Results After pSL139 plasmids being digested and for 40 minutes agarose gel of electrophoresis, 3.75 kb fragment of target gene and vector were observed. The cells were almost uniform, and triangular or diamond shape after 24-48 hours of culture; the cells turned to fusion manner and could be passaged after 4-6 days. Desmin immunofluorescent result showed that green fluorescence was seen in cytoplasm of most 2nd myoblasts, and the purity of the myoblasts was above 90%. At 48 hours after transfection of myoblasts with plasmid pSL139, RT- PCR results showed that about 300 bp fragment was seen in the experimental group and the control group, and the brightness was higher in experimental group. Immunofluorescent staining displayed that green fluorescence was seen in the cytoplasm of the myoblasts in the experimental group and no green fluorescence in the control group; the expression efficiency of positive cells for micro-dystrophin was 45%-55% in experimental group. Conclusion Micro-dystrophin gene can highly express at the levels of mRNA and protein respectively in myoblasts transfected with plasmid pSL139 mediated by l iposome.
ObjectiveTo approach the role of CD4+CD25+ regulatory T cells in the maintenance of immunotolerance in mouse liver allograft. MethodsThe mouse orthotopic liver transplantation was performed. After the liver transplantation immunotolerance induction, antiCD25 monoclonal antibody (PC61) was injected into the recipients with a delayed timing to remove the CD4+CD25+ T cells. The percentage of CD4+CD25+ T cells and the expression of forkhead/winged helix transcription factor (Foxp3) in the recipients were examined. Furthermore, the survival time of the recipient was observed. ResultsC3H/HeJ recipients receiving DBA/2 hepatic allografts survived over 70 d as in the syngeneic liver transplantation (C3H/HeJ recipients receiving C3H/HeJ hepatic grafts). With various protocols of the delayed PC61 treatment, the CD4+CD25+ T cell was completely disappeared as observed. However, the removal of CD4+CD25+ regulatory T cells after the induction of transplantation immunotolerance did not affect the survival of hepatic allografts. ConclusionCD4+CD25+ regulatory T cells are not essential for the maintenance of spontaneous mouse liver transplantation immunotolerance.
【Abstract】ObjectiveTo investigate the effect of RNA editing enzyme ADAR1 on the function of lymphocyte immune by transferring mouse lymphocytes with plasmid of sense siRNA and by suppressing the expression of ADAR1. MethodsThe cell strains of human hepatic cellular carcinoma （HCC） were frozen and thawed repeatedly to prepare for tumor soluble antigen. The isolated mouse lymphocytes, which were transferred with antisense siRNA plasmid of ADAR1 and were sensitized with soluble tumor antigen were used as the study group; those which were not transferred but were sensitized were used as the control group. The 3HTdR adulteration experiment was used to test the sensitivity of lymphocytes. The effect of ADAR1 on lymphocyte immunity was detected by lymphocytotoxicity tests. ResultsThe observation of the isolated lymphocytes implied that the growth cycle of lymphocyte was 10-14 days. The 3HTdR adulteration experiment showed the result was optimal. The number of HCCs decreased significantly for both of the groups compared with those in the blank holes, but the amplitude was much larger in the control group. The expression of ADAR1 in lymphocytes of the study group was significantly lower than that of the control group, which demonstrated that the RNA plasmid of ADAR1 suppressed the expression of ADAR1 in sensitized lymphocytes and the suppressing rate of the control group (87.47±4.62)% was significantly higher than that of study group （53.19±3.95）%. The function of lymphocytes killing targetcells in the study group was significantly inferior to that of control group (P＜0.05). ConclusionRNA editing enzyme ADAR1 may play an important role in mouse cellullar immunologic response and it is possible to attenuate the cellimmune response by depressing the expression of ADAR1.
ObjectiveTo investigate whether miR-93-5p suppresses osteogenic differentiation of mouse mesenchymal stem cells (C3H10T1/2) by targeting Smad5, a predicted target in silicon. MethodsSmad5 3'-UTRluciferase vector (pmiR-RB-REPORTTM) was constructed and dual-luciferase reporter gene assay was employed to examine the effect of miR-93-5p on Smad5 3'-UTR-luciferase activity to identify whether Smad5 was the target gene of miR-93-5p. miR-93-5p mimics (group M), miR-93-5p inhibitor (group In), miR-93-5p mimics negative control (group MC), and miR-93-5p inhibitor negative control (group InC) were transfected into the C3H10T1/2 cells, respectively, and followed by induction of osteogenic differentiation. After 48 hours, the real-time fluorescent quantitative PCR (qRTPCR) and Western blot assays were performed to detect the relative expressions of Smad5 mRNA and protein. At 14 days, to realize the regulation role of miR-93-5p in osteogenic differentiation, the extracellular calcium deposition during the osteogenesis of C3H10T1/2 cells was tested by Alizarin red staining. ResultsDual-luciferase reporter gene assay showed that miR-93-5p could combine with Smad5 mRNA 3'-UTR specificity, and inhibited its luciferase activity (P<0.05). After 48 hours, no significant difference was shown in the relative expression of Smad5 mRNA between group M and group MC as well as between group In and group InC by qRT-PCR assay (P>0.05); however, the results of Western blot assay showed that the relative expression of Smad5 protein was significantly decreased in group M and increased in group In when compared with groups MC and InC (P<0.05). At 14 days after osteogenic induction, Alizarin red staining showed that the extracellular calcium deposition of group M was obviously less than that of group MC, and it was obviously more in group In than in group InC. ConclusionSmad5 may be the target gene of miR-93-5p. And miR-93-5p can suppress osteogenic differentiation of C3H10T1/2 cells by directly targeting Smad5.
Objective To make a mouse model of traumatic spinal cord injury (SCI) by Allen’s weight dropping (WD),which might be helpful for further research on the mechanism of SCI. Methods A total of 180 healthy female mice, weighing 17 - 23 g (20 g on average), were randomized into 4 groups (n=45 per group): the experimental groups of A, B and C and the control group of D. Experimental groups were distinguished by the amount of weight or the height from which the weight was dropped onto an impounder resting on the dura (2.0 × 2.5 g·cm, 2.5 × 3.0 g·cm, 3.0 × 5.0 g·cm). In group D, neural scute was opened only and spinal cord was exposed without SCI. The recovery of the lower extremity was observed at various time points (0,6 and 12 hours, 1 and 3 days, 1, 2, 4 and 8 weeks) by using the Basso mouse scale (BMS) scoring system, motor evoked potentials (MEP) and histological observation. Results MEP displayed that the incubation period of N1 wave was extended in group B after 6 hours and in group C after 12 hours. As time passed by, the incubation periods of N1 wave in group A, group B and group C began to shorten. The incubation period in group A was close to normal at 4 weeks (2.40 ± 0.12) ms, and there was no significant difference compared with group D (P gt; 0.05). The incubation period in group B was close to normal at 8 weeks (2.96 ± 0.15) ms, and there was no significant difference compared with group D (P gt; 0.05). The incubation period in group C was still relatively high at 8 weeks (3.76 ± 0.13) ms, and there was a significant difference compared with group D (P﹤0.05). Both hind l imbs of all mice were paralytic instantly after SCI, the score of main BMS was 0 point; the score of main BMS was close to 0 at the first 3 days after SCI, the score of main BMS of group A was 8.00 ± 0.13 and group B was 7.50 ± 0.31 at 8 weeks;the score of main BMS of group A was 5.45 ± 0.12 at 1 week and group B was 5.45 ± 0.15 at 2 weeks which were significant difference compared with group D (P﹤0.05).There were significant differences among groups A, B and C after 1 week of SCI (P lt; 0.05), and group C was lower than the others(P﹤0.01). The score of adjuvant BMS of group A was 10.12 ± 0.76 at 2 weeks and group B was 9.85 ± 0.55 at 8 weeks which was no significant difference compared with the group D at the same time (P gt; 0.05). Histological observation showed hemorrhage, cellular edema, inflammatory cell infiltration, nerve cell swell and solution of Nissl body 12 hours after SCI in group C. As time passed by, the number of nerve cells decreased, the gl ial cell prol iferated and Nissl body vanished. There was much gl ial cell prol iferation and cavitation 2 weeks after SCI in group C. The nerve cell decrease and cavitation in group B was sl ighter than that in group C, and group A was the sl ightest. In group D, there was no obvious change of the number of cells during the observation apart from sl ight edema in early period. Conclusion The mouse model precisely reflects the pathological and physiological features and law of change after different degrees of SCI, and can be used as a standard of mouse model of traumatic SCI by Allen’s WD.