Flash and Bones - Kathy Reichs [26]
Tight nod.
My mind sorted through possibilities.
“It couldn’t be a funeral-home mix-up. They don’t do pickups on Sundays.”
“And everyone else is accounted for.”
“When did you notice the John Doe missing?”
“About an hour ago. I went into the cooler to collect a gunshot case.”
“Was anyone in here over the weekend? Cleaning crew? Maintenance? Repair service?”
Larabee shook his head.
“Joe was on duty?”
“Yes.”
When alone on night shift, Joe sleeps on a cot in the back of the men’s room. Closed door. Bad ears. An army could march through and he wouldn’t hear a thing.
“Is it possible someone broke in?” I asked.
“And stole a corpse?” Larabee sounded beyond skeptical.
“It happens.” Defensive.
“Body snatchers would have needed to disarm the security system.”
“And tinkering is supposed to trigger an alarm.”
“Supposed to.” Larabee’s tone affirmed his cynicism about modern technology.
“Let’s check for signs of forced entry.”
We did.
Found none.
“This is insane.” I was at a loss for more ideas.
“There’s something I should tell you.” Larabee and I were standing beside the roll-on scale at the receiving dock.
I looked a question at him.
“Let’s go to my office.” Now the ME sounded nervous.
We entered and Larabee closed the door. He sat behind his desk. I took a chair facing him.
“As I was leaving on Saturday, I got tagged by the FBI.”
I took a wild guess. “Special Agents Williams and Randall?”
Larabee glanced at a paper lying on his blotter. “Yes. They were asking about the John Doe.”
“What did you tell them?”
“I shared my autopsy findings and your bio profile. I said I’d collected samples for tox analysis and warned that a final report would take time.”
“And?” I asked.
“Williams offered to deliver the samples personally. Said he’d try to get them bumped up the queue. I called the Charlotte field office. The two are legit, so it seemed kosher to me. I asked Joe to handle it.” Larabee’s brows dipped sharply. “A report faxed in around ten this morning.”
“You’re kidding.” I was astonished. Normally it takes weeks, even months, to get lab results.
“My mention of pulmonary lesions and edema coupled with gut ulceration and hemorrhage must have triggered something for Williams. He had my specimens driven to the CDC and fast-tracked through immunochromatographic analysis.”
Larabee referred to a type of immunoassay, a chemical test designed to detect organic substances. I wasn’t an expert but knew a little about the process.
Short course.
Antigens are molecules recognized by our immune systems as outsiders. Could be toxins, enzymes, viruses, bacteria. A transplanted lung that looks wrong. Antibodies are proteins that attack and neutralize these foreign invaders.
Antibodies are present normally in our bodies or are produced in response to specific antigens. This is known as an immune reaction.
Immunoassay tests are based on the ability of antibodies to bind to specific antigens. Threat X triggers response Y. Gotcha! In forensics, the technique is used to identify and quantify unknown organic compounds in samples. This antibody reacted, so this substance must be present.
I waited.
“The test indicated the presence of ricin in two of my samples.”
“Ricin?” I couldn’t keep the surprise from my voice.
Ricin is a naturally occurring toxin derived from the beans of the castor-oil plant, Ricinus communis. One of the deadliest poisons known, it can cause death in thirty-six to seventy-two hours after exposure.
In addition to binding specificity, the other key feature of an immunoassay is that the test produces a measurable signal in response to a particular antigen-antibody hookup. In the case of ricin, a green light is given off. That’s the chromatographic part of the long term.
The green light is measured by a spectrophotometer or similar piece of equipment. Basically, the brighter the glow, the more ricin there is in a sample.
Larabee nodded.
“That explains the fast turnaround time,” I said.
In the past few years immunoassay testing has become quick