Good vs. Evil: part deux
By Dr. Chiaramonte–
When we left off in the 1880s, Dr. Blackley had traced clues that hinted at the existence of IgE, the allergic antibody, and in 1911, the English Doctors Noon and Freeman were homing in on the blocking antibody IgG. In any war, new intelligence comes in that must be interpreted, and in this one, the scientists could not yet tell the allies from the enemy.
In 1921 Doctors Prausnitz and Küstner found some key phenomena concerning the allergic agents and blocking agents. Küstner had clinical symptoms after eating fish, and developed a positive immediate response to fish when he applied it to his skin. Prausnitz was not allergic to fish and had a negative immediate skin test response. In the spirit of Dr. Jekyll, he injected a small amount of Kustner’s blood serum into Prausnitz’s own skin. Fortunately, the evil Mr. Hyde response after two days was confined to that site and lasted a few weeks. He became, in effect temporarily allergic to fish at that spot. This allergic antibody was not detectable by any other means. This temporary reactivity is now known as a P-K reaction after our two intrepid laboratory adventurers. It can be prevented by moderately heating the serum before injecting.
Some time later, other researchers did a similar experiment with pollen allergy. They found that serum drawn from a subject who had undergone immunotherapy with pollen created a blocking effect on the P-K reaction.
Without going into too much detail—this is after all a website, not an encyclopedia, suffice it to say that when the immune system is involved, we can sometimes only tell when a patient has developed antibodies when we see a known reaction.
In this case, the allergic antibody was called a reaginic, or skin-sensitive antibody, and detectable by only the P-K reaction. It was heat sensitive, and thought to have only one site available to combine with the antigen, which meant it didn’t leave enough evidence of itself to be detected in a test tube. The blocking antibody was heat stable with multiple sites to combine with the antigen; it threw off plenty of evidence. Now at last there was a way of telling the friendlies from the enemy.
Next Time: Good vs. Evil—Where there’s smoke, there’s fire