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Objective To investigate the role of interleukin-1 receptor type 1 (IL-1R1) signaling in H1N1 influenza virus infection. Methods IL-1R1 knockout ( IL-1R1-/-) mice and wild type ( WT) mice were infected intranasally with 2×104 TCID50(50% tissue culture infective dose) of influenza virus H1N1 PR8. Changes in clinical signs, survivals and bodyweights of those mice were monitored daily for 14 consecutive days. Three mice from each group were sacrificed at 3, 7 and 14 days post infection (d. p. i), from which whole lungs were harvested. A part of the lobes was fixed in 4% paraformaldehyde for histopatho-logical assessment and the rest were split and stored at-80 centigrade for further analysis. Real-time quanti-tative PCR and cytometric bead array ( CBA) were performed to detect viral loads in lungs and inflammatory cytokines in supernatants of lung homogenates. Results The mice in both groups showed severe symptoms after the infection of PR8. The maximum bodyweight loss of IL-1R1-/- mice [(24. 22±0. 80) % at 8 d. p. i] was lower than that of WT mice [(28. 03±1. 51)% at 9 d. p. i] (P<0. 05). The IL-1R1-/- mice with PR8 infection showed a higher survival rate (90%) as compared with that of the control group (40%) (P<0. 05). No statistical differences in virus loads were observed between the two groups at 3, 7 and 14 d. p. i. The lung weight to body weight ratio of IL-1R1-/-mice [(1. 42±0. 03) %] was lower than that of WT mice [(1. 79±0. 08) %] at 3 d. p. i (P<0. 05). Pathological changes in IL-1R1-/- mice were less severe than those in WT mice. CBA detection assay revealed that the proinflammatory cytokines in lungs of IL-1R1-/-mice were less than those in WT mice. Conclusion IL-1R1 signaling plays a pathogenic role in mice infec-ted with 2×104 TCID50 of influenza virus PR8 by promoting inflammatory responses.
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Objective To analyze the Alb-cre/DTR mouse phenotype, and establish a model of induced liver damage to serve basic researches of liver diseases.Methods The introduced Alb-cre and DTR mice were crossed to obtain Alb-cre/DTR mice and the genomic DNAs were extracted from the tail tissue of the mice for genotying by PCR.Diphtheria toxin was intraperitoneally(i.p.)injected into the Alb-cre/DTR mice, then the body weights were monitored and the sera were collected for the detection of serum ALT and AST levels.Results By crossing Alb-cre and DTR mice we obtained the Alb-cre and DTR double transgenic mouse.The intraperitoneal injection of diphtheria toxin in a dose of 0.625 ng/g body weight significantly induced liver injury in these mice, as showed by the elevated levels of ALT and AST, the gross appearance of liver damage and the pathological changes such as necrosis in the liver tissue.Conclusions We have ob-tained a novel mouse strain of Alb-cre/DTR by crossing Alb-cre and DTR mice.Liver damages in those Alb-cre/DTR mice can be induced by injection of diphtheria toxin.This established mouse model of inducible liver damage is a useful platform for the studies of liver damage and recovery, as well as liver transplantation.
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Objective To establish uPA inducible expression system using recombinant retroviral system for the further construction of inducible uPA-SCID animal model .Methods The Inducible expression system need to construct two plasmids:pLNHXO1O2-Alb-GLUC-FMN2A -rtTA and pLNHXO5O6-TRE2-uPA-IRES-ZsGreen respectively. Both plasmids were based on retroviral vector pLNHX , Albumin promoter gene ( Alb) and rtTA gene or uPA gene and ZsGreen were obtained by PCR reaction and inserted into pLNHX .The Gaussia enzyme fluorescent element ( GLUC) was used to monitor rtTA expression in pLNHXO1O2-Alb-GLUC-FMN2A-rtTA, and the ZsGreen for uPA expression monitoring in pLNHXO5O6-TRE2-uPA-IRES-ZsGreen.The correct constructed plasmids were transfected into packaging cell line GP 2-293 to gain recombinant viral particles .NIH/3T3 cells were infected with these viral particles and selected with G 418.Gene expression in the surviving cells was confirmed by the PCR method .Results The recombinant retroviral vectors harbouring target genes were successfully cloned .The rtTA gene in pLNHXO1O2-Alb-GLUC-FMN2A-rtTA was expressed, and uPA can be induced to express in pLNHXO5O6-TRE2-uPA-IRES-ZsGreen by doxycycline (Dox) when the plasmid transfected into the HepG-Tet-on cell.The constructed recombinant two retroviral vectors were transfected into GP 2-293 packaging cells respectively to gain infectious viral particles .Then,NIH/3T3 cells were infected with these viral particles and single-cell clones which stably expressed the transgenes were successfully established .Conclusion This study primarily established uPA inducible expression system , it laid a foundation for the murine model of inducible liver damage , and provided a novel technical platform for further building the liver humanised murine models for viral hepatitis studying .
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Liver diseases post great threats to human public health globally.Lacking of appropriate small animal models largely impeded the translational studies on human liver diseases, especially on viral hepatitis and related cirrhosis, hepatocellular carcinoma, etc.By human hepatocyte transplantation, the liver-humanized mice have significantly contribu-ted to the researches of human liver diseases.This review summarizes the currently widely used and representative human-ized mouse models, including uPA, FAH, TK-NOG, AFC8 mice and their applications in studies of human liver diseases.
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Objective To elucidate the influences of epitope competition on the frequency and average intensity of specific T cell response.Methods C57BL/6 mice were immunized with either single epitope DNA vaccines (pSV-gag92 or pSV-env203) or fusion gene DNA vaccine (pSV-gag/env).Gag92and Env203 epitope-specific CD8 T cell responses were analyzed by intracellular cytokine staining assay.Results Gag92-specific IFN-γ+CD8 T cells that were induced by pSV-gag92 accounted for 0.415 00％ ±0.045 88％ of the total CD8 T cells,which was much more than that induced by pSV-gag/env of 0.058 67％ + 0.019 64％.Moreover,the mean fluorescence intensity of Gag92-specific TNF-α-IFN-γ+CD8 T cells (296.70+14.08) elicited by pSV-gag/env was significantly lower than that of Env203-specific TNF-α-IFN-γ+CD8 T cells (818.00+49.34).Conclusion Epitope competition could significantly decrease both the frequency and the average intensity of specific T cell response to subdominant epitopes.
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Biotic tissues are a kind of highly scattering random media; studies on laser light propagation in biotic tissues play an important role in bio-medical diagnostics and therapeutics. The propagation and distribution of infinitely narrow photon beam in tissues are simulated by Monte Carlo method in this paper. Also presented are the energy distribution with regard to depths, light distribution in tissues, reflection and transmittance on the upper and lower surface. The optical parameters adopted in this study are g, albedo and microa, which have influence on energy distribution. The results show: The energy distribution decreases more quickly with the increase of depths and reveals a peak value close to the surface; g factor plays an important part in the lost energy on the upper surface and lower surface; the decrease of g factor causes weaking of the forward moving ability, so the penetration depth becomes smaller and the energy becomes dispersives variation of albedo has distinct effect on the shallow and deep tissues.