Date:   5/27/2007 3:16:59 AM ( 18 y ago)
Hits:   8,276
URL:   https://www.curezone.org/forums/fm.asp?i=880381

http://www.pnas.org/cgi/content/abstract/103/41/15154


BIOLOGICAL SCIENCES / MEDICAL SCIENCES
A purified Bacillus thuringiensis crystal protein with therapeutic activity against the hookworm parasite Ancylostoma ceylanicum

Michael Cappello*,, Richard D. Bungiro*, Lisa M. Harrison*, Larry J. Bischof, Joel S. Griffitts, Brad D. Barrows, and Raffi V. Aroian,

*Program in International Child Health, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520; and Section of Cell and Developmental Biology, University of California, San Diego, CA 92093

Communicated by Bruce Alberts, University of California, San Francisco, CA, August 14, 2006 (received for review June 20, 2006)

Crystal (Cry) proteins produced by the soil bacterium Bacillus thuringiensis (Bt) are harmless to vertebrates, but they are highly toxic to insects and nematodes. Their value in controlling insects that destroy crops and transmit human diseases is well established. Although it has recently been demonstrated that a few individual Bt Cry proteins, such as Cry5B, are toxic to a wide range of free-living nematodes, the potential activity of purified Cry proteins against parasitic nematodes remains largely unknown. We report here studies aimed at characterizing in vitro and in vivo anthelminthic activities of purified recombinant Cry5B against the hookworm parasite Ancylostoma ceylanicum, a bloodfeeding gastrointestinal nematode for which humans are permissive hosts. By using in vitro larval development assays, Cry5B was found to be highly toxic to early stage hookworm larvae. Exposure of adult A. ceylanicum to Cry5B was also associated with significant toxicity, including a substantial reduction in egg excretion by adult female worms. To demonstrate therapeutic efficacy in vivo, hamsters infected with A. ceylanicum were treated with three daily oral doses of purified Cry5B, the benzimidazole anthelminthic mebendazole, or buffer. Compared with control (buffer-treated) animals, infected hamsters that received Cry5B showed statistically significant improvements in growth and blood hemoglobin levels as well as reduced worm burdens that were comparable to the mebendazole-treated animals. These data demonstrate that Cry5B is highly active in vitro and in vivo against a globally significant nematode parasite and that Cry5B warrants further clinical development for human and veterinary use.


And Shroom, maybe you can make something of this:


http://www.sciencemag.org/cgi/data/307/5711/922/DC1/1


Stumbled on that after bumping into page on (ugh..) PubMed regarding resistance to Bt in humans:


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abs...


The nematode, Caenorhabditis elegans, can be mutated to resistance to the Cry5B toxin of Bacillus thuringiensis. By Cloning and characterization of these C. elegans resistance genes, we have determined that a major mechanism by which C. elegans resists Cry5B is by loss of function mutations in any one of four gylcosyltransferase genes that glycosylate glycolipids specific to arthropods. Without correct gylcosylation, binding of Cry5B is greatly impaired in C. elegans. That these specific arthroseries glycolipids do not occur in vertebrates potentially helps explain why Cry toxins are specific for arthropods.

BTW: My brother told me when we were discussing this before that it can be found in any gardening dept. (Home Depot, etc.) Anyone for Cry5B cocktails, my house - say 7PM???


 

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