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ARIZONA REPUBLIC (Phoenix) 24 November 04 Mexican lab a leader in taking sting out of venom (Chris Hawley)
CuernavacA, Mexico: The black widow spider twitched in the grip of an electric shock, drops of silk oozing from its abdomen, as a lab technician probed its fangs with a needle-shaped glass pipe.
"There it is," said Dr. Alejandro Alagón Cano, as a barely visible drop of venom filled the end of the pipe. He peered at the drop approvingly as the exhausted spider was lifted off an electrical wire and plopped back into a beaker. "That's enough venom to put you in terrible pain for two days."
Unless you have the antidote, of course.
And that's where Alagón and other scientists at his Mexican laboratory come in.
Researchers here at the Biotechnology Institute in Cuernavaca, 30 miles south of Mexico City, are impressing foreign doctors with their cures for some of the deadliest poisons Mother Nature has devised.
Arizona officials are especially interested. They're trying to import a cutting-edge scorpion antivenin invented at the lab and eagerly are testing the lab's black widow and rattlesnake antidotes.
"I'm glad they're discovering us because I know many American patients will suffer less," Alagón said.
All manner of fanged varmints populate the toxins lab at the Biotechnology Institute, part of the National Autonomous University of Mexico. During a recent visit, baby black widows hung out on a web in an old CD-ROM box. A scorpion shuffled around a glass jar. On a lab bench, newborn rats the size of peanuts squirmed and squeaked in a plastic bag - lunch for the tarantulas.
Master's student Herlinda Clemente Carretero held up a brown recluse spider in a Petri dish.
"This one bites you and causes a sore, and then your skin starts to rot. Sometimes it keeps rotting right up your arm," she said matter-of-factly.
Using the institute's recipes, workers at commercial laboratories in Mexico now "milk" thousands of scorpions, black widows and other dangerous critters, inject their poison into horses, and then turn the horse blood into antidotes.
By cutting up proteins in the antidote, they've eliminated the violent allergic reactions and "serum sickness" caused by treatments available in the United States.
Leslie Boyer, medical director of Arizona's Poison and Drug Information Center, said she discovered the lab's work while accompanying a National Geographic television reporter to Mexico to help with a documentary on dangerous animals.
She brought some of Arizona's scorpions, which send about 100 people, mostly children, into hospital intensive-care wards every year.
To demonstrate the power of the Mexican antidote, a scientist at the Cuernavaca lab stung a mouse with one of the scorpions, waited as the mouse began to succumb to the poison, and then cured it instantly with a single injection.
"It was the wildest thing you ever saw," Boyer said. "I said, 'I don't know what's in that vial, but I want it.' "
Boyer is now leading efforts to get U.S. Food and Drug Administration approval for the antivenin, known as Alacramyn in Mexico and Anascorp in the United States. The crude antivenin now being used in Arizona no longer is made, and supplies probably will run out this year.
Arizona hospitals also are testing the Mexican black widow antidote, which is far safer than its U.S. counterpart. Black widow bites are most common in the American Southwest, said Chris Stanford, who is managing the tests from the Rocky Mountain Poison and Drug Center in Denver. There are about 10 cases a year in Arizona, Boyer said.
An advanced rattlesnake antidote developed by the lab is also being tried out in Arizona. The current American treatment requires a series of shots and costs up to $20,000. The Mexican cure is one-tenth the cost, Alagón said. About 300 people a year are bitten by rattlesnakes in Arizona.
The Mexican researchers have pulled ahead of their U.S. counterparts simply because there are more snake bites, scorpion stings and spider bites in Mexico, Boyer said.
Over the years, the scientists in Cuernavaca have learned to tinker with the genes of E. coli bacteria to turn them into little antidote factories. They've already done it with the black widow antivenin, meaning the horses soon may no longer be needed.
The scientists also have taught bacteria to produce the flesh-rotting venom of the brown recluse spider as a first step toward a cure. Researcher Laura Olguín Pérez keeps an icy vial of the poison in a small refrigerator.
The bacteria themselves live in a high-security commercial laboratory, Alagón said.
He said an escape would cause no danger. The concentration of poison is so low that a few quarts of the bacteria would be needed to hurt a human.
The laboratory also is refining an antidote for bites of the coral snake, a threat in states from Texas to Florida. The coral snake common to Arizona is less poisonous, Boyer said.
Although their work involves taking the danger out of dangerous critters, the scientists said they respect the animals they're trying to disarm. Alagón talks about "accidents" when he means stings and bites and says he refuses to see the movie Arachnophobia because "I know it would make me angry."
He smiled and waved a hand around his laboratory, chock full of poisonous predators.
"You work with these little guys for a while, and you start to get fond of them," he said.
Mexican lab a leader in taking sting out of venom

That is the best news I have heard since the creation of Cro-Fab, which takes much higher doses & costs much more than the antidote it replaced.

~~Greg~~

I echo your comment Greg. It figures it would take a lab in a country who's trying to help it's people rather drain their bank account. I think it's called Humanitariumism a word never uttered in board rooms in this country.

Al
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You can't enjoy your collection if it kills you.

Al: Don't blame US. If I'm not mistooken, Cro-Fab is made in Australia.

~~Greg~~

Crofab is made in OZ??

If so, then it shows how much Austrailia knows about US venom.
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Chad Bachman

Oz makes the cleanest most effective AV, (along with SAVP) and I can't see how they would make an AV so useless as Crofab, unless our snake venoms are that complicated, and complex.
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Chad Bachman

>>Al: Don't blame US. If I'm not mistooken, Cro-Fab is made in Australia.

Cro-Fab is made by a multinational company, Protherics, with offices in the US, UK and Australia. Parts of the CroFab production process take place in Australia and the UK. They have nothing to do with Commonwealth Serum Labs, the Australian antivenom manufacturers. Check their website: http://www.protherics.com/company/default.htm

Part of the problem is that they decided to use Fab fragments (a smaller part of the immunoglobulin molecule than the more usual Fab2 parts used in most antivenoms), the idea being to (i) reduce the incidence of adverse reactions, and (ii) increase the penetration of the AV into tissues that may be out of reach to larger molecules.

Point (i) seems to have worked out fairly well, but point (ii) much less so. The major drawback of the smaller molecule is that the body gets rid of it much faster, so you may need additional doses to mop up venom that is being released into the bloodstream after the initial dose of antivenom has been eliminated by the body. The expense probably has as much to do with development costs in the face of major regulatory requirements (FDA etc.) as anything else.

Cheers,

WW
Protherics

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WW Home

Mexico AV rocks, you will see!!

Crofab is still better than Wyeth, but they both need/needed alot of work.
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Chad Bachman