A Bacteriophage T4 Nanoparticle-Based Dual Vaccine against Anthrax and Plague.

Bacillus anthracis and Yersinia pestis, the causative agents of anthrax and plague, respectively, are two of the deadliest pathogenic bacteria that have been used as biological warfare agents. Although Biothrax is a licensed vaccine against anthrax, no Food and Drug Administration-approved vaccine exists for plague. Here, we report the development of a dual anthrax-plague nanoparticle vaccine employing bacteriophage (phage) T4 as a platform. Using an in vitro assembly system, the 120- by 86-nm heads (capsids) of phage T4 were arrayed with anthrax and plague antigens fused to the small outer capsid protein Soc (9 kDa). The antigens included the anthrax protective antigen (PA) (83 kDa) and the mutated (mut) capsular antigen F1 and the low-calcium-response V antigen of the type 3 secretion system from Y. pestis (F1mutV) (56 kDa). These viral nanoparticles elicited robust anthrax- and plague-specific immune responses and provided complete protection against inhalational anthrax and/or pneumonic plague in three animal challenge models, namely, mice, rats, and rabbits. Protection was demonstrated even when the animals were simultaneously challenged with lethal doses of both anthrax lethal toxin and Y. pestis CO92 bacteria. Unlike the traditional subunit vaccines, the phage T4 vaccine uses a highly stable nanoparticle scaffold, provides multivalency, requires no adjuvant, and elicits broad T-helper 1 and 2 immune responses that are essential for complete clearance of bacteria during infection. Therefore, phage T4 is a unique nanoparticle platform to formulate multivalent vaccines against high-risk pathogens for national preparedness against potential bioterror attacks and emerging infections.IMPORTANCE Following the deadly anthrax attacks of 2001, the Centers for Disease Control and Prevention (CDC) determined that Bacillus anthracis and Yersinia pestis that cause anthrax and plague, respectively, are two Tier 1 select agents that pose the greatest threat to the national security of the United States. Both cause rapid death, in 3 to 6 days, of exposed individuals. We engineered a virus nanoparticle vaccine using bacteriophage T4 by incorporating key antigens of both B. anthracis and Y. pestis into one formulation. Two doses of this vaccine provided complete protection against both inhalational anthrax and pneumonic plague in animal models. This dual anthrax-plague vaccine is a strong candidate for stockpiling against a potential bioterror attack involving either one or both of these biothreat agents. Further, our results establish the T4 nanoparticle as a novel platform to develop multivalent vaccines against pathogens of high public health significance.

[Effects of different phosphorus application rates on growth, 15N-urea absorption, and utilization characteristics of pear rootstocks.] / ä¾›ç£·æ°´å¹³å¯¹æ¢¨ç §æœ¨ç”Ÿé•¿å’Œ15N-å°¿ç´ å¸æ”¶åˆ©ç”¨ç‰¹æ€§çš„å½±å“.

Three kinds of potted one-year-old pear rootstocks (Pyrus calleryana, P. pashia, and P. xerophila) and 15N trace technique were used to examine the effects of different phosphorus application rates (P0, P1, P2, P3 and P4 equivalent to 0, 50, 100, 150 and 200 kg·hm-2 P2O5, respectively) on plant growth and the characteristics of 15N-urea absorption and utilization. The results showed that, with the increases of phosphorus levels, plant height, ground diameter, dry mass, root surface area, root length, number of root tips, root activity, root respiration rate, Ndff values, and nitrogen use efficiency of rootstocks first increased and then decreased. However, the range of rise and fall of different rootstocks were distinct, and each index reached the highest level at different phosphorus levels. The plant height, diameter, dry mass of P. xerophila were the highest under the same phosphorus level, followed by P. pashia, and P. calleryana was the lowest. The root architecture parameters and root respiration rate showed the same trend, but Ndff values and nitrogen use efficiency performed different. Under different phosphorus levels, each index of P. xerophila reached the highest level at P3, but those of P. pashia and P. calleryana appeared at P2 and P1 rates, respectively. The Ndff values in stem were the highest among different organs of rootstocks at diffe-rent phosphorus levels, and the highest nitrogen use efficiency of P. xerophila, P. pashia and P. calleryana was 9.6%, 8.9% and 8.3%, respectively. The variations of plant growth and N absorption and utilization of different pear rootstocks across different phosphorus levels indicated that phosphorus fertilizer should be carry out reasonably in practice and give full consideration of phosphorus demands of plants.

Estimation of contribution ratios of pollutant sources to a specific section based on an enhanced water quality model.

Because water quality monitoring sections or sites could reflect the water quality status of rivers, surface water quality management based on water quality monitoring sections or sites would be effective. For the purpose of improving water quality of rivers, quantifying the contribution ratios of pollutant resources to a specific section is necessary. Because physical and chemical processes of nutrient pollutants are complex in water bodies, it is difficult to quantitatively compute the contribution ratios. However, water quality models have proved to be effective tools to estimate surface water quality. In this project, an enhanced QUAL2Kw model with an added module was applied to the Xin'anjiang Watershed, to obtain water quality information along the river and to assess the contribution ratios of each pollutant source to a certain section (the Jiekou state-controlled section). Model validation indicated that the results were reliable. Then, contribution ratios were analyzed through the added module. Results show that among the pollutant sources, the Lianjiang tributary contributes the largest part of total nitrogen (50.43%), total phosphorus (45.60%), ammonia nitrogen (32.90%), nitrate (nitrite + nitrate) nitrogen (47.73%), and organic nitrogen (37.87%). Furthermore, contribution ratios in different reaches varied along the river. Compared with pollutant loads ratios of different sources in the watershed, an analysis of contribution ratios of pollutant sources for each specific section, which takes the localized chemical and physical processes into consideration, was more suitable for local-regional water quality management. In summary, this method of analyzing the contribution ratios of pollutant sources to a specific section based on the QUAL2Kw model was found to support the improvement of the local environment.

Mutated and bacteriophage T4 nanoparticle arrayed F1-V immunogens from Yersinia pestis as next generation plague vaccines.

Pneumonic plague is a highly virulent infectious disease with 100% mortality rate, and its causative organism Yersinia pestis poses a serious threat for deliberate use as a bioterror agent. Currently, there is no FDA approved vaccine against plague. The polymeric bacterial capsular protein F1, a key component of the currently tested bivalent subunit vaccine consisting, in addition, of low calcium response V antigen, has high propensity to aggregate, thus affecting its purification and vaccine efficacy. We used two basic approaches, structure-based immunogen design and phage T4 nanoparticle delivery, to construct new plague vaccines that provided complete protection against pneumonic plague. The NH2-terminal ß-strand of F1 was transplanted to the COOH-terminus and the sequence flanking the ß-strand was duplicated to eliminate polymerization but to retain the T cell epitopes. The mutated F1 was fused to the V antigen, a key virulence factor that forms the tip of the type three secretion system (T3SS). The F1mut-V protein showed a dramatic switch in solubility, producing a completely soluble monomer. The F1mut-V was then arrayed on phage T4 nanoparticle via the small outer capsid protein, Soc. The F1mut-V monomer was robustly immunogenic and the T4-decorated F1mut-V without any adjuvant induced balanced TH1 and TH2 responses in mice. Inclusion of an oligomerization-deficient YscF, another component of the T3SS, showed a slight enhancement in the potency of F1-V vaccine, while deletion of the putative immunomodulatory sequence of the V antigen did not improve the vaccine efficacy. Both the soluble (purified F1mut-V mixed with alhydrogel) and T4 decorated F1mut-V (no adjuvant) provided 100% protection to mice and rats against pneumonic plague evoked by high doses of Y. pestis CO92. These novel platforms might lead to efficacious and easily manufacturable next generation plague vaccines.

[Effect on therapeutic effect of inducing the formation of the post-moxibustion sore for bronchial asthma].

OBJECTIVE: To observe the impact of inducing the formation of the post-moxibustion sore on the efficacy of bronchial asthma treated with scarring moxibustion. METHODS: Three hundred and seventy-two cases diag nosed definitely as bronchial asthma at remission stage were randomly divided into a modified nursing group (248 cases) and a conventional nursing group (124 cases). The scarring moxibustion was applied at Dazhui (GV 14), Feishu (BL 13), Danzhong (CV 17) and Tiantu (CV 22) in either group. The direct moxibustion with moxa cone was adopted. In modified nursing group, 0.5% Iodine was used for the sterilization at moxa abscess. The herbal plaster was cut into an inverted triangle and compressed on the wound. After suppuration, the fester was not cleaned in each dressing change. Additionally, the patients were advised to have high-protein diets after moxibus tion till abscess dropped. In conventional nursing group, 0.5% Iodine was used for the sterilization at moxa abscess. The herbal plaster was cut into a round shape that could cover completely the moxa wound. After suppuration, in each dressing change, the wound was cleaned and sterilized. Additionally, the patients were advised to avoid any stimulating food after moxibustion till abscess dropped. The clinical efficacy, the change of C3 content in blood serum and the clinical symptom score were observed in two groups. RESULTS: The total effective rate was 93.5% (232/248) in modified nursing group, which was better than 79.0% (98/124) in conventional nursing group (P < 0.01). C3 content increased apparently after treatment as compared with that before treatment in either group (both P < 0.01), but C3 level increased much more apparently in modified nursing group as compared with that in conventional nursing group (P < 0.01). The clinical symptom score reduced apparently after treatment in either group (both P < 0.01), but that reduced much more apparently in modified nursing group as compared with that in conventional nursing group (P < 0.01). CONCLUSION: In the treatment of bronchial asthma with scarring moxibustion, to induce the formation of the post-moxibustion sore achieves the better clinical efficacy as compared with conventional nursing.

Synergetic effect of yihuo qingyi decoction (see text) and recombinant staphylokinase in treatment of severe acute pancreatitis of rats.

OBJECTIVE: To investigate the effect of recombinant staphylokinase (r-Sak) and the Chinese medicine Yihuo Qingyi Decoction ((see test) Herbal decoction for severe acute pancreatitis) in the treatment of the severe acute pancreatitis (SAP) in rats, and to observe the synergistic effect of the two. METHODS: One hundred and sixty-two adult male SD rats with the body mass of 250-280 g were randomly divided into the following 5 groups: sham operation group (n = 18), control group (n = 36), Yihuo Qingyi Decoction treatment group (n = 36), r-Sak treatment group (n = 36), and Yihuo Qingyi Decoction plus r-Sak treatment group (n = 36). The SAP ratmodel was prepared by retrograde injection of 5% sodium taurocholate into the cholangiopancreatic duct. Two days before modeling, Yihuo Qingyi Decoction was intragastrically administrated, and r-Sak was intraperitoneally injected. The survival rate within 18 h after modeling was determined. The pancreatic blood flow, the weight of ascites, and the serum amylase and lipase were investigated at 6 h, 12 h, and 18kh after modeling, and the pancreatic tissue was examined under light microscopy to see its pathological change. RESULTS: The 18 h survival count of group A, B, C, D and E rats was 9, 2, 6, 7 and 8 respectively. After r-Sak and Yihuo Qingyi Decoction intervention, the serum amylase and lipase and the weight of ascites were significantly decreased, especially in group E.18 h after modeling, the level of the serum amylase and lipase and the weight of ascites in group E was 1 100 +/- 118 U x L(-1), 1 000 +/- 150 U x L(-1) and 13.40 +/- 1.80 g respectively, obviously lower than that of group B (P < 0.05). After SAP was induced, the pancreatic blood flow showed a tendency to decrease, but the decrease extent in the treatment groups was smaller than that in the control group. 18h after modeling, the pancreatic blood flow in group B and group E was 30.16 +/- 8.96 mL x 100 g(-1) x min(-1), and 129.10 +/- 42.58 mL x 100 g(-1) x min respectively, there was significant difference (P < 0.05). The pathological change of the pancreatic tissue was alleviated in the treatment groups. CONCLUSION: Both r-Sak and Yihuo Qingyi Decoction play a beneficial role in the treatment of rat SAP and there is a synergistic effect between the two.

[Effects of Radix Salviae Miltiorrhizae on the PMN-EC adhesion in vitro at the early stage of endotoxemia].

OBJECTIVE: To evaluate the effects of Radix Salviae Miltiorrhizae (RSM) on the PMN-EC adhesion in vitro at the early stage of endotoxemia, and to probe into the mechanism there in involved. METHODS: The rabbit endotoxemia model was made, and one group was treated with RSM injection (2 ml/kg) instantly and 24 h after the modeling of endotoxemia. PMN-EC adhesion rate, adhesion molecule (CD11a/CD18 and CD11b/CD18) and TNF-alpha level were measured instantly, 2 h, 4 h, 8 h, 16 h, 24 h and 48 h after endotoxemia modeling. RESULTS: It was found that after the modeling of endotoxemia, the levels of CD11a/CD18, CD11b/CD18 and PMN-EC adhesion rate instantly increased in the endotoxemia group and RSM group, they went up to the peak at 4 h in the endotoxemia group, and at 2 h, 4 h, 8 h, 16 h, 24 h and 48 h, they were markedly lower in the RSM group than in the endotoxemia group (P < 0.05). The TNF-alpha level in the endotoxemia group began to increase 2 h after the modeling and reached to the peak at 8 h, with its level still higher than normal at 48 h, while the RSM group had lower level of TNF-alpha at all time-points(P < 0.05). CONCLUSION: The data from this animal experiment indicate that Radix Salviae Miltiorrhizae can decrease PMN-EC adhesion rate and the levels of CD11a/CD18, CD11b/CD18 and TNF-alpha in case of endotoxemia so as to improve the microcirculation.