January 30, 2009
UNIT 6: Classification and DiversityB Memory Cells Still Remember 1918 Flu Virus
How long do the immune system’s B memory cells remember? Recent studies focused on the 1918 H1N1 influenza virus have finally given researchers a clue. In late 2008, lab tests revealed that survivors of the 1918 influenza pandemic could still produce the specific antibodies their immune systems used to fight the 1918 flu virus. When a pathogen, such as the 1918 flu virus, enters the body, some B cells become activated to produce antibodies, while other B cells produce memory cells. B memory cells “remember” how to make an antibody for a particular pathogen. If the pathogen attacks again, the B memory cells produce B cells that make antibodies to fight the pathogen.
In 2005, investigators recovered preserved 1918 flu virus samples from bodies of flu victims found frozen in Alaskan soil. A team of researchers then took blood samples from 32 survivors of the 1918 flu pandemic, who are now between the ages of 91 and 101 years old. Then researchers put the virus to the test in the lab. Test results confirmed that the antibodies from blood samples of the surviving flu victims were still able to fight the 1918 flu virus! The B cells of the survivor’s immune systems could still secrete antibodies that bound to the 1918 antigen. These B cells, made specifically to fight the 1918 antigen during the pandemic, had waited between 60 to 90 years for a second round with the virus.
The 1918 flu pandemic is the most devastating on record, having killed nearly 50 million people worldwide. The fact that survivors of the pandemic have antibodies that can still fight the 1918 flu nearly 90 years later is a major breakthrough in immune system research. It’s possible that these antibodies could be used to develop treatments for future outbreaks of flu strains similar to the 1918 virus.