January 15, 2014

A new strain of Clostridium botulinum encoding a novel toxin, BoNT/H the eight such toxin, has been described, the first such toxin to be described in >40 years (Barash et al., 2014; Dover et al., 2014). 

The authors referred their concerns up the line. Journal editors and US security agencies were involved resulting in the publication of the work without description of the toxin itself. The original paper was published accompanied by a letter from the editors describing the review process and decision (Hooper & Hirsch, 2014), a historical overview of botulinum toxins (Popoff, 2014) and a comment from David Relman, former member of the NSABB and one who handled the original Kawaoka and Fouchier papers (Relman, 2014).

While the efficiency and merits of redacting essential data from a paper can be debated, the example is well worth reading for the authors flagged up their concerns and shared their observations and difficulties with other stakeholders. It shows that complex and worrying biological issues can be shared and acted upon. The accompanying review papers make for good reading.

A note at the end of the editor’s letter (Hooper & Hirsch, 2014) lists the large number of committees that were involved in commenting on the larger dimensions of theses findings.

“A committee representing various branches of the US government reviewed and approved submission of the manuscripts. Represented on this committee were the Drug Development Section, Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH); the Enteric and Hepatic Diseases Branch, NIAID, NIH; the Bacteriology and Mycology Branch, NIAID, NIH; the Office of Biotechnology Activities, Office of Science Policy, NIH; the National Counterproliferation Center, Office of the Director of National Intelligence; the Office of the Assistant Secretary for Preparedness and Response, Department of Health and Human Services (DHHS); the Biomedical Advanced Research and Development Authority, Office of the Assistant Secretary for Preparedness and Response, DHHS; the Threat Characterization and Attribution Branch, Chemical and Biological Defense Division, Science and Technology Directorate, Department of Homeland Security; the US Army Medical Research Institute of Infectious Diseases; the Division of Select Agents and Toxins, Office of Public Health Preparedness and Response, Centers for Disease Control and Prevention, DHHS; and the Biological Countermeasures Unit, Federal Bureau of Investigation Weapons of Mass Destruction Directorate, Department of Justice.”

The last paragraph from Relman’s letter is worth reading.

“Finally, for voluntary controls to play a useful role in the management of problematic information in the “gray area,” scientists will first need to recognize their ethical and moral responsibilities to society in the pursuit of knowledge. Scientists have obligations to society that involve more than blind pursuit of information. Like clinicians, scientists have an obligation to do no harm.”

References
A novel strain of Clostridium botulinum that produces type B and type H botulinum toxins.
Barash JR, Arnon SS.
J Infect Dis. 2014 Jan 15;209(2):183-91. doi: 10.1093/infdis/jit449. Epub 2013 Oct 7.


Molecular characterization of a novel botulinum neurotoxin type H gene.
Dover N, Barash JR, Hill KK, Xie G, Arnon SS.
J Infect Dis. 2014 Jan 15;209(2):192-202. doi: 10.1093/infdis/jit450. Epub 2013 Oct 7.


Novel clostridium botulinum toxin and dual use research of concern issues.
Hooper DC, Hirsch MS.
J Infect Dis. 2014 Jan 15;209(2):167. doi: 10.1093/infdis/jit528. Epub 2013 Oct 7. 


Botulinum neurotoxins: more and more diverse and fascinating toxic proteins.
Popoff MR.
J Infect Dis. 2014 Jan 15;209(2):168-9. doi: 10.1093/infdis/jit505. Epub 2013 Oct 7. 


"Inconvenient truths" in the pursuit of scientific knowledge and public health.
Relman DA.
J Infect Dis. 2014 Jan 15;209(2):170-2. doi: 10.1093/infdis/jit529. Epub 2013 Oct 7. 

January 2014

Alternative reassortment events leading to transmissible H9N1 influenza viruses in the ferret model.
Kimble JB, Angel M, Wan H, Sutton TC, Finch C, Perez DR.
J Virol. 2014 Jan;88(1):66-71. doi: 10.1128/JVI.02677-13. Epub 2013 Oct 16.

Kimble et al., describe inoculation of ferrets with MDCK (dog) cells transfected by 15 plasmids for avian H9N2 flu strain and human pandemic 2009 H1N1 (minus the H1 hemagglutinin). Theoretically 128 reassortant viruses can be made. Two of three animals so inoculated became infected giving rise to what were called lineage A and B viruses. Within 4 days of transfection, the dye was cast and one combination quickly dominated in each infected animal. This contrasts to the findings for tissue culture that once again highlights the need for animal studies.

At the end of 4 manual passages (P1-P4 virus) a fifth passage by aerosol transmission with P4 virus was attempted for three infected animals and it worked (RCP5 virus, RC=respiratory contact). P1 and RCP5 viruses were sequenced. There were 4 non-synonymous nucleotide changes (i.e. resulting in amino acid changes) for lineage A virus and 6 (5 non-synonymous, 1 synonymous, or silent change) for lineage B virus. None of the mutations overlapped. None were in the HA receptor binding pocket. This shows that there are many constellations that compatible with aerosol transmission using 6 common genes (PB2, PA, HA, NP, NA, and NS, Table 1). 2/4 and 5/5 mutations were of unknown phenotype indicating once again the wide gap in correlating genotype and phenotype.

The authors did not sequence the P4 virus used to initiate the aerosol transmission experiment hence we cannot work out which mutations arose during serial mechanical passage and which resulted from selection via transmission. It is unlikely that all 4 and 6 mutations arose during the single aerosol transmission passage, hence the numbers so acquired must be <4 and <5 for lineage A and B. Sequencing the P4 virus would have established the precise number involved.

Their interest in GOF is shown by the last sentence: “A similar approach can be implemented to ascertain the gene constellation that would most likely lead to more effective respiratory-droplet transmission of other avian influenza viruses in mammals.” Sequencing the P4 virus would have helped.