Bacillus Anthracis Issues

The CDC is investigating an unintentional release of anthrax  from the Department of Defense (DOD) to multiple labs in multiple states.  An article from Voice of America indicates 24 labs in 11 states and 2 countries (South Korea and Australia) have received "suspect samples" of concern.

Anthrax has quite a history, both in its naturally occuring state and as a biological weapon, as documented by the Center for Disease Control (CDC).  There have been a number of anthrax "releases" over time,  Recently, in 2014 there was a release at CDC's Roybal Campus .  The year 2001 saw a wave of anthrax attacks.  A CDC review discusses the 2001 attacks in some detail as well as discussing epidemiological findings. and provides a history of anthrax., both in a naturally occurring state and as a biological weapon.

One interesting development has been the appearance of bacillus anthracis in heroin used by European drug users.  The strain involved originated in Turkey, raising a question as to how bacillus anthracis would get into the heroin supply.

The CDC provides basic information on Bacillus Anthracis.  The bacteria Bacillus Anthracis exists in a dormant, sporulated state in nature, can enter the body by a variety of routes (e.g. cutaneous or inhalation pathways), become activated, spread throughout the body, multiply and produce toxins.

These incidents all represent an interesting pattern in the release of bacillus anthracis into the biosphere, taking into consideration emerging environmental issues regarding climate change.  The question is to what extent the environment adapts or reacts to environmental challenges thrown its way.

As this CDC case investigation indicates, it is difficult to investigate individual cases of anthrax when they occur.  Human cases of anthrax are rare, despite the fact that Bacillus Anthracis can be found naturally in the soil and commonly infects domestic and wild animals throughout the world.  There may be a number of reasons for this apparent paradox, which is under investigation.

My blog article "Panspermia and Evolution" discusses Bacillus Anthracis and the distribution of life in the context of extreme environments.  These are the types of situations involving low probability, high impact events.

Bacillus Anthracis is mentioned in a few of my blog articles, "Evolution of Adaptive Immunity" and in an article on "Ebola".

Bacillus Anthracis needs oxygen in order to sporulate.. This is a very interesting characteristic that may provide clues to it's activity, especially in the human body. Iron is a key element in the human body, intimately associated with a number of metabolic processes, including its role in hemoglobin and the delivery of oxygen throughout the body.

Indeed, Bacillus Anthracis uptakes iron when exposed to superoxide stress.   Bacillus anthracis experiences rapid sporulation in a high iron, glucose free environment.  Apparently, Bacillus Anthracis may operate as a signaling mechanism triggering iron accumulation when exposed to environmental stresses, impacting the iron catalyst of the  Fenton reaction.

Transferrin blocks growth of Bacillus Anthracis via iron deprivation, an effect that is differentially expressed in cutaneous anthrax vs inhalational anthrax. This difference, in the latter case, is due to phagocytosis by macrophages, a process which occurs upon inhalation, allowing the inhaled spores to germinate intracellularly, multiply and cause infection.

It is apparent that Bacillus Anthracis forms the heart of a mystery, a challenge, as we seek to better understand the manner in which it expresses, affecting a number of medical processes in the human body. At the same time, we examine other issues impacting society on a global level, issues of climate change, global warming and their interactions with the changing environment in which we live.  These issues will be discussed in further blog articles.

Center for Disease Control (CDC):
  CDC Investigating unintentional DoD shipment of anthrax
  Anthrax
  A History of Anthrax
  CDC Director Releases After-Action Report on Recent Anthrax Incident
  CDC Responds to Anthrax - 2001
  Review of Fall 2001 Anthrax Bioattacks
  Injectional Anthrax in Heroin Users - 2000 -2012
  Anthrax - Basics
  Investigation of Inhalational Anthrax Case - United States

Voice of America -"Carter Vows to Find Those Responsible for Anthrax Shipment"

American Veterinary Medical Association (AVMA) - Anthrax FAQ

marilyndunstan.blogspot.com
   Panspermia and Evolution
   Evolution of Adaptive Immunity
   Ebola

Medical Microbiology - Bacillus
Journal of Bacteriology - Cellular Iron Distribution in Bacillus Anthracis
Journal of Microbiological Methods - Rapid Sporulation of Bacillus Anthracis in a high iron-glucose free media
Journal Biological Chemistry - Human Transferrin Confers Serum Resistance Against Bacillus anthracis

IUPAC - Gold Book - Fenton Reaction

Wikipedia:
  Oxidative Stress
  Phagocytosis
  Macrophage

Evolution of Adaptive Immunity

Two Trees (creative digital image)

I attended a "Weiser Endowed Lecture in Immunology" featuring Dr Max Cooper of the Emory University School of Medicine, speaking on "Evolution of adaptive immunity" at the University of Washington in 2012.  Dr Cooper's work is foundational in this subject area.

It is interesting that immunity systems follow a phylogenetic pathway much as the phylogeny of species themselves do. The evolutionary pathway of jawless vertebrates (of whom hagfish and lampreys are surviving members), possess differences in comparison to the common evolutionary pathway followed by other vertebrates.

Lampreys and hagfish do not possess a thymus , nor do they possess a spleen.    Lampreys and hagfish do not possess Major Histocompatibility Complex (MHC) 1 or 2, T-cell receptors or recombination activating genes (RAG 1 and 2) which play an active role in the recombination of T-cell and immunoglobulin  receptors. Lampreys and hagfish posses hematopoietic tissue, the former in the intestine and the latter in the portal vein.  With these changes, the lampreys and hagfish diverged off the common immune system evolutionary pathway prior to the development of certain MHC class immunity in other species.  This is an important benchmark due to the major role that the MHC class plays in vertebrates.  It is a vital aspect which makes the concept of a separate phylogenetic pathway earmarked for the immune system so interesting.  If lampreys do not possess a thymus, then what substitutes in its place?

Lampreys and hagfish utilize a system of leucine-rich repeats )(LRR's) to mediate immune system responses using Variable Lymphocyte Receptor (VLRs), (VLRA's, VLRB's and VLRC's).  The interesting aspect of the jawless vertebrate immune system function is comparing its action in structure and function to the immune systems we are familiar with.  VLRB's have structures similar to toll like receptors (proteins that play a key role in the innate immune system), while their functions are similar to those of antibodies,  and they possess humoral characteristics (using macromolecules in extracellular fluids in immunity systems). They act using discrete populations of lymphocytes (types of white blood cells) .

VLRBs act as an adaptive immune system and can differentiate foreign from self in recognizing lymphocytes.

Lampreys posses a diverse variety of leucine-rich repeats which code for germline and mature genes. They possess a specificity for carbohydrate and protein receptors on bacterial and mammalian cells. They bind antigens with high avidity and affinity, describing the binding capacity of multiple versus single interactions of antibodies with antigenic epitopes.

 In "Evolutionary implications of a third lymphocyte lineage in lamprey", the authors find a thymoid source for VLRA and VLRC assembly in the lamprey gill tips, while VLRB assembly occurs in hematopoietic typhosole and kidney tissues.  VLRC appeared more numerous than VLRA, and predominated in the skin.  They conclude that a similar body plan of two T-cell type lymphocytes in a thymoid type structure and one B-cell type lymphocyte in the blood and kidneys shows some similarity in basic structure to the immune system for jawed vertebrate, while achieving adaptive immunity through different means.

Monclonal VLRB antibodies  from immunized lamprey larvae can recognize plasma cells from myeloma patients.  VLR4, a monoclonal VLRB specific for BclA, the bacillus collagen-like protein, has shown to be specific for B. Anthracis spores.  Information on B. Anthracis can be obtained from the US Centers for Disease Control (CDC) CDC - Anthrax and the World Health Organization (WHO) WHO - Anthrax.

Research indicates a number of applications where VLR's can recognize certain immumogens  An immunogen is any antigen that is capable of inducing humoral and/or cell-mediated immune response rather than immunological tolerance.  These applications include diagnosis, research and bioterrorism investigations.