Development and application of an analytical method for the determination of squalene in formulations of anthrax vaccine adsorbed

Advances in the Metabolic Engineering of Escherichia coli for the Manufacture of Monoterpenes

Monoterpenes are commonly applied as pharmaceuticals and valuable chemicals in various areas. The bioproduction of valuable monoterpenes in prokaryotic microbial hosts, such as E. coli, has progressed considerably thanks to the development of different outstanding approaches. However, the large-scale production of monoterpenes still presents considerable limitations. Thus, process development warrants further investigations. This review discusses the endogenous methylerythritol-4-phosphate-dependent pathway engineering and the exogenous mevalonate-dependent isoprenoid pathway introduction, as well as the accompanied optimization of rate-limiting enzymes, metabolic flux, and product toxicity tolerance. We suggest further studies to focus on the development of systematical, integrational, and synthetic biological strategies in light of the inter disciplines at the cutting edge. Our review provides insights into the current advances of monoterpene bioengineering and serves as a reference for future studies to promote the industrial production of valuable monoterpenes.

Chemical composition and biological activity of seed oil of amaranth varieties

The work is devoted to study of seed oil composition of amaranth varieties: Kharkov, Lera, Andijan and Helios, acclimatized in Uzbekistan. We demonstrated the possibility of using reversed-phase HPLC using a refractometric detector, which allows simultaneous determination of squalene and triacylglycerides in plant seeds and determining the authenticity of amaranth oils. Established seed oiliness ranged from 6.39 to 7.81 % of the initial mass. Amaranth oil samples contained quite large amount of unsaturated fatty acids 72.72 – 73.28 %, 1.17 % of which is omega-3-alpha-linolenic acid. The squalene content in the seeds ranged from 0.35 % to 0.55 %. It was established that the squalene content in oils obtained by extraction is greater than the one obtained by cold pressing. In the triacylglyceride composition of the investigated cold-pressed and extracted oils, no significant differences were found.

An improved RP-HPLC method for simultaneous analyses of squalene and cholesterol especially in aquatic foods

A simple, rapid and simultaneous method for the quantitative evaluation of squalene and cholesterol in oil recovered from different body parts of fresh water and marine fish species was developed using reverse phase High performance liquid chromatography (RP-HPLC). A modified fractional crystallization method was developed using absolute ethanol as a solvent to obtain a fraction of squalene and cholesterol in the oil extracted from different body parts of fish samples. Elution of squalene and cholesterol was carried out isocratically with 100 % acetonitrile at 195 nm by diode array detector. Excellent linearity of the calibration curve was observed. The limit of detection for squalene and cholesterol were found to be 5.0 ng ml(-1) and 1.0 μg ml(-1) respectively. A possible correlation was established by determining the ratio between cholesterol and squalene which was found to be ranging from 2 to 10. This method was successfully employed for the determination of squalene and cholesterol in the above mentioned samples.

Safety review: squalene and thimerosal in vaccines

Few studies show the reluctance of the people to get vaccinated against A (H1N1) influenza for fear of side effects of squalene (MF59, AS03, AF03) and thimerosal. The aim of this paper is to assess the safety in using these adjuvants and preservative reviewing data of clinical trials relative to which formulation includes these compounds. In the current state of knowledge, these vaccines have proved to be effective even though they more frequently give local adverse events than non-adjuvanted influenza vaccines. Systemic side effects are generally not serious. In the studies, adjuvanted vaccines do not increase neither the risk of Guillain Barre syndrome nor auto-immune diseases. There is no convincing evidence that exposure to thimerosal in vaccines had any deletorious effect on physiological outcome.

Squalene selectively protects mouse bone marrow progenitors against cisplatin and carboplatin-induced cytotoxicity in vivo without protecting tumor growth

Squalene, an isoprenoid antioxidant is a potential cytoprotective agent against chemotherapy-induced toxicity. We have previously published that squalene protects light-density bone marrow cells against cis-diamminedichloroplatinum( II) (cisplatin)-induced toxicity without protecting tumor cells in vitro. Here, we developed an in vivo mouse model of cisplatin and cis-diammine (cyclobutane-1,1-dicarboxylato) platinum(II) (carboplatin)-induced toxicity to further investigate squalene-mediated LD-BM cytoprotection including the molecular mechanism behind selective cytoprotection. We found that squalene significantly reduced the body weight loss of cisplatin and carboplatin-treated mice. Light-density bone marrow cells from squalene-treated mice exhibited improved formation of hematopoietic colonies (colony-forming unit-granulocyte macrophage). Furthermore, squalene also protected mesenchymal stem cell colonies (colony-forming unit-fibroblast) from cisplatin and carboplatin-induced toxicity. Squalene-induced protection was associated with decreased reactive oxygen species and increased levels of glutathione and glutathione peroxidase/glutathione-S-transferase. Importantly, squalene did not protect neuroblastoma, small cell carcinoma, or medulloblastoma xenografts against cisplatin-induced toxicity. These results suggest that squalene is a potential candidate for future development as a cytoprotective agent against chemotherapeutic toxicity.

Enhancement of an analytical method for the determination of squalene in anthrax vaccine adsorbed formulations

Specific lots of anthrax vaccine adsorbed administered to members of the U.S. Armed Forces have been alleged to contain squalene, a chemical purported to be associated with illnesses of Gulf War veterans. A method of enhanced sensitivity for determining squalene in anthrax vaccine adsorbed using high-performance liquid chromatography with photodiode array detection has been developed, validated, and applied to 44 bottles of 38 lots of anthrax vaccine. In 43 bottles of 37 lots, no squalene was detected within a detection limit of 1ng/0.5ml dose (2 parts-per-billion). One lot, FAV008, was found to contain trace amounts of squalene at 7, 9, and 1microgl(-1), levels considerably below normal human plasma levels (290microgl(-1)). The overall results of this investigation provide direct evidence for the absence of squalene in nearly all of anthrax vaccine preparations tested.

New-onset rheumatoid arthritis after anthrax vaccination

BACKGROUND

Anthrax vaccine was licensed in 1970 and is used to protect individuals exposed to biological warfare and those who may come in contact with Bacillus anthracis in infected animals or in laboratory settings. The current adsorbed anthrax vaccine is regarded as effective and safe. Adverse effects reported include fever, chills, myalgia, arthralgia, and nausea. Four cases of rheumatoid arthritis (RA) temporally related to anthrax vaccine have been reported. As the number of administered doses increases, a better understanding of its adverse events profile will be forthcoming.

OBJECTIVE

To describe another patient with RA temporally related to anthrax vaccination.

METHODS

A 42-year-old man developed bilateral knee stiffness and pain in all the proximal interphalangeal joints 5 days after receiving the first dose of anthrax vaccine. He reported chills, fever, and joint and neck pain, with a tender nodule at the injection site after dose 2. Hours after receiving dose 3 he experienced fever, chills, nausea, vomiting, and neck, hand, and shoulder pain. The vaccination series was terminated after the third dose.

RESULTS

Physical examination revealed moderate swelling and tenderness of his bilateral proximal interphalangeal joints. His complete blood cell count was normal; rheumatoid factor level, 198 IU/mL; erythrocyte sedimentation rate, 53 mm/h; antinuclear antibodies, negative; C-reactive protein level, 2.7 mg/L; and anti-cyclic citrullinated peptide antibody level, 168 EU. Radiographs revealed mild degenerative changes in his hands and knees bilaterally.

CONCLUSIONS

This case represents a fifth patient with RA temporally related to anthrax vaccine.

Anthrax Vaccines

The current human anthrax vaccines licensed in the US and UK consist of aluminum hydroxide-adsorbed or alum-precipitated culture supernatant material from fermentor cultures of toxigenic noncapsulated strains of Bacillus anthracis. The threat of B. anthracis being used as a biowarfare agent has led to a wider usage of these vaccines, which has heightened concerns regarding the need for frequent boosters and the occasional local reactogenicity associated with vaccination. These concerns have provided the impetus for the development of better characterized vaccines. This review summarizes the work of numerous laboratories in the search for alternative vaccines against anthrax that are well tolerated, provide long-lasting immunity, and are efficacious.

Is osteoporosis linked to vaccinations and Gulf War Syndrome?

Gulf War Syndrome (GWS) remains a contentious diagnosis with conflicting laboratory investigations and lack of a biologically plausible aetiology. Assertions have been made that GWS may be the result of vaccinations given to serving military personnel in the Persian Gulf and may be associated with osteoporosis. Calcitonin gene related protein (CGRP) is a vasoactive neuropeptide that is synthesised in conjunction with calcitonin gene expression. Vasoactive neuropeptides act as hormones, neurotransmitters, immune modulators and neurotrophes. They are readily catalysed to small peptide fragments. They and their binding sites are immunogenic and are known to be associated with a range of autoimmune conditions. This paper describes a biologically plausible mechanism for the development of osteoporosis in the context of GWS based on loss of immunological tolerance to the vasoactive neuropeptide CGRP or its receptors following a variety of antigenic events.

Detection of antibodies to squalene

An ELISA-based assay is described for the measurement of antibodies to squalene (SQE) in human serum and plasma. The assay was adapted from the previously described assay for murine antibodies to SQE (J. Immunol. Methods 267 (2002) 119). Like the murine SQE antibody assay, the human antibody assay used sterile cell culture 96-well plates coated with SQE (20 nmol/well). Phosphate-buffered saline (PBS)-0.5% casein was used as both a blocking agent and dilution buffer. The assay has a high through-put capacity and is reproducible and quantitative. This assay was used to evaluate samples from three different human cohorts. The first cohort was retired employees of the United States Army Medical Research Institute of Infectious Diseases (USAMRIID alumni). The mean age was 68 (N=40; range 58-82). Most were vaccinated with the U.S. licensed anthrax vaccine (AVA) and most had received several other vaccines through a USAMRIID special immunization program. The second cohort was of similar age (N=372; mean age 67; range 54-97) from the normal population of Frederick, MD and were not vaccinated with AVA. The third cohort (N=299) was from Camp Memorial Blood Center, United States Army Medical Department Activities, Fort Knox, KY. (No additional volunteer information is available.) Using this new ELISA method, antibodies to SQE were detected in all three of the cohorts. IgG antibodies to SQE were detected in 7.5% and 15.1% of the samples from the USAMRIID alumni and Frederick cohorts, respectively. These differences were not significantly different (chi((1))(2)=1.69, p=0.19). In contrast, no IgG antibodies to SQE were detected in the Fort Knox cohort which is significantly different than the Frederick cohort (chi((1))(2)=49.25, p<0.0001). IgM antibodies to SQE were detected in 37.5% and 32.3% of the samples from the USAMRIID and Frederick cohorts, respectively, but there was no significant difference between the cohorts. In the Fort Knox cohort, 19.4% of the samples were positive for IgM antibodies to SQE, which was significantly different from the Frederick cohort (chi((1))(2)=14.23, p=0.0002). Although the age of the volunteers from the Fort Knox cohort is unknown, the demographic of the donors at the blood bank volunteers is 85% 17-21 years of age. This suggested that the prevalence of antibodies to SQE may increase with age. This was confirmed with mouse studies in which the presence of antibodies was monitored as a function of time. No antibodies to SQE were detected in female BALB/c, B10.Br and C57BL/6 mice at 2 months of age, but they reached a maximum prevalence with 100% and 89% of animals testing positive for IgG and IgM antibodies to SQE, respectively, in the C57Bl/6 mice at 18 months of age. BALB/c and B10.Br mice also developed antibodies to SQE over time, but were at a lower prevalence than those observed in the C57BL/6 mice. Thirty-five of the 40 volunteers in the USAMRIID were vaccinated with AVA (mean no. doses=26; range 3-47). Comparison of the prevalence of antibodies to SQE from the AVA immunized group with the Frederick cohort revealed that there was no statistical differences for IgG (chi((1))(2)=2.3, p=0.13) or IgM (chi((1))(2)=0.33, p=0.56). When the data from the USAMRIID and Frederick cohorts were combined and analyzed for the presence of antibodies to SQE with respect to the sex of the volunteer, females (40.8%) were found to have a higher prevalence of IgM antibodies to SQE than men (28.4%) (chi((1))(2)=6.59, p=0.01). No significant difference was observed in the prevalence for IgG antibodies to SQE in females (17.7%) and males (12.5%). We conclude that antibodies to SQE occur naturally in humans; have an increased prevalence in females; are not correlated with vaccination with AVA; and appear to increase in prevalence with age.