If one of the greatest gifts is to discover early in life what you are meant to do, then Charles (Chuck) Kristensen, 49, must be counted among the lucky ones. He found his calling in 1973, at 22, while working for an entomologist at the University of Minnesota. "I spent a lot of time watching spiders," he recalls. All that webmaking, spider mating and insect catching resonated with something in his personality--he still can't say what. "It just nailed me," he says. "I knew I would be working with spiders for the rest of my life."
The evidence of Kristensen's arachnophilia sits, silent and menacing, in thousands of plastic cups and modified deli containers in the basement of his unkempt and funky-smelling suburban house in Feasterville, Pa., just north of Philadelphia. Arrayed on tray-size boards and more than 20 6-ft.-tall racks are some 50,000 living spiders representing dozens of species: sleek, lacquered western black widows, hairy fishing spiders, palm-size Gramostola spatulata from Chile, even a fist-size, cocoa-brown African king baboon tarantula.
This is the livestock of Spider Pharm, a mom-and-pop operation that Kristensen began as a hobby in 1980 and that has since grown into the most active purveyor of spider venom in the world.
"Spider venom is a gold mine of pharmacological tools," explains Michael Adams, a venom-using neuroscientist at the University of California at Riverside. The active compounds in venom bind with extreme selectivity to molecules on the surfaces of living cells, a property that can be of invaluable use to researchers developing new medicines with better specificity (and thus fewer side effects) or just trying to understand, at the molecular level, the inner workings of living cells.
A venom purchased from Kristensen in the 1980s, for example, helped neuroscientist Rodolfo Llinas of New York University School of Medicine discover a new calcium channel involved in the communication between certain neurons, shedding new light on how the mind works. Another toxin extracted from Spider Pharm venom in 1995 by Kenton Swartz at the National Institutes of Health (named hanatoxin after Swartz's daughter) is being used to probe the function of proteins that are located on cellular membranes and have been implicated in diseases ranging from diabetes to epilepsy.
How does one extract venom from a tiny, delicate and perhaps deadly spider? In a word: carefully. Kristensen and his wife Anita start by tranquilizing the specimen with a gentle breeze of carbon-dioxide gas from a cylinder behind the milking desk. Once the spider is groggy, the milker, peering through a low-power stereoscopic microscope, gently picks it up with metal tweezers that are connected to an electrical supply. When a mild shock is administered through the tweezers, the spider promptly spews up pretty much everything liquid inside it--including digestive enzymes. That was a problem early on, until Chuck devised a combined "mouthwash" and venom-collecting system that keeps the two fluids separated using a hollow suctioning needle and a miniature glass pipette.