Ability to test effectiveness of pneumonia vaccine
is a key step to prevent deaths from S. pneumoniae.
Newswise, October 17, 2016 – As a child in war-ravaged Korea,
Moon Nahm, M.D., decided his life’s goal would be to create a company and use
its profits to fund research. Instead, the Korean-born researcher grew up to
build what a recent National Institutes of Health review calls “a national
treasure” — the World Health Organization Pneumococcal Serology Reference
Laboratory at the University
of Alabama at Birmingham.
Nahm uses the lab to help achieve a new goal — affordable
pneumonia vaccines for the world. His groundbreaking research is on the
threshold of aiding researchers in producing vaccines at prices that will
propel their widespread use and help protect the estimated 1.6 million
children, most of them under the age of 5, who die yearly from S. pneumoniae
infections. S. pneumoniae is the leading cause of pneumonia.
“We need to reduce the cost for use in developing countries —
from more than $100 a dose in the United States to less than $10 per dose,”
Nahm said. “That is a key goal for the World Health Organization and the Bill
& Melinda Gates Foundation.”
One of Nahm’s crucial discoveries was a method to rapidly and
inexpensively test whether a vaccine candidate effectively elicits antibodies
that can kill the S. pneumoniae bacteria.
The test — developed, improved and validated through years of
painstaking work by Nahm’s research team — is vital in Korean, Chinese, Indian
and other efforts to develop new generic vaccines.
Nahm’s patents and more than 70 license agreements have made
him one of the most prolific inventors at UAB, as measured by licensing income.
He is a professor in the UAB Department of Medicine, division of Pulmonary,
Allergy and Critical Care Medicine, and director of the WHO Reference
Laboratory.
“Very few careers have been as impactful as Dr. Nahm’s,”
writes Bernard Beall, Ph.D., chief of the Streptococcus lab at the National
Center for Infectious Diseases, Centers for Disease Control and Prevention.
“Dr. Nahm’s impressive work in immunology, polysaccharide chemistry, cell
biology, vaccinology and many different areas can be described as nothing short
of pioneering.”
Why the need for vaccines?
S. pneumoniae bacterial strains are cloaked by a polysaccharide capsule that protects them from phagocytic cells in the lungs and blood during lung infections. Effective vaccines produce antibodies that can bind to the capsule and help phagocytes engulf and destroy the bacteria, thus preventing disease and saving lives.
Pneumonia vaccine creation is challenging because pneumococci
have a welter of different capsule types. Instead of just one, pneumococci have
97 different capsule serotypes, seven of them discovered by Nahm.
Current vaccines target the 23 most dangerous serotypes for
adult vaccines and the 13 most threatening for young childhood vaccines.
Evaluating the effectiveness of a potential generic vaccine
against all these different serotypes is difficult, especially since
researchers can get only small amounts of serum from vaccinated young children
for use in testing.
Nahm was able to develop an assay to look at antibody response
to vaccination that requires only one-fourth of the serum used in previous
tests.
He and his team rigorously validated the assay, found a way to
make the pneumococcal colonies in the assay turn red for automated counting,
and developed a software package to quickly analyze assay data.
More than 100 lab workers across the globe have come to Nahm’s
UAB World Health Organization lab to learn this critical, fourfold multiplexed
opsonophagocytic-killing assay, and six more will arrive this month for
training. The UAB lab also produces standardized reagents for the assay.
As Nahm was developing an NIH pneumococcal reference lab in
the 1990s, he turned it into something greater than a routine testing lab.
Under Nahm’s leadership, the lab became a launch pad to study
and improve existing assays, and create new assays. One breakthrough was his
finding that the then-accepted second-generation ELISA assay lacked specificity
to quantitate human antibodies against pneumococcal polysaccharides.
Nahm developed and validated the third-generation assay that
was adopted by World Health Organization experts in 2000. “That’s how our lab
became the WHO lab,” Nahm said.
Beall, of the CDC, writes, “In my opinion, Dr. Nahm is the
world’s foremost authority in pneumococcal capsular structure and immunology.
We in the public health arena absolutely depend upon this scientist’s unique
insights into the ever-changing serologic landscape of this devastating
pathogen.”
Journey to the United States
Nahm was born in Seoul, Korea, just before the Korean War erupted in 1950. His family evacuated to the city of Busan, on the southern coast of Korea, during the war.
“I had to fetch water from a well before sunrise, walking over
icy hills in the dark by touch,” Nahm said. “If I waited until after sunrise,
the well would be empty.”
By the early 1960s, Korea was still relatively poor.
“Electricity supply was so irregular in Korea that I remember
wondering why one would bother to make an electrical clock,” Nahm said of his
childhood. “Centralized heating of a house was inconceivable.”
In 1964, Nahm’s father, a medical doctor who had trained in
the United States, decided to move the family to St. Louis. This was well ahead
of the surge in Korean emigration to the United States in the 1970s and 1980s.
Nahm suddenly found himself an American high school senior, needing to find a
college.
He went to Washington University, where he graduated summa cum
laude in physics and earned an M.D. degree. Nahm then decided to study
infectious disease, noting its potential threat to human existence, as seen in
the Black Death that killed one-fourth of Europe’s medieval population.
Ties to his homeland
Throughout his career, Nahm has kept strong ties with Koreans and Korean-Americans. He has mentored many Korean researchers and has also served on the scientific advisory group for the International Vaccine Institute, Seoul.
Nahm was chosen as one of the 20 outstanding Korean medical
scientists by the Korean Medical Association in 2002, and he is one of 50
Korean-Americans profiled in the recent book “Korean Leaders LEADING America.”
As Nahm gained stature as a researcher, Korea also prospered,
growing into the nation with the 11th-highest total GDP in the world.
“Now, in the 21st century,” Nahm wrote in a recent 50th
reunion letter to his classmates from Kyunggi High School, Seoul, “I can feel
the rise of Koreans on the world stage, along with many successful
Korean-Americans in the USA.”
“I would never have guessed such changes were possible while I
was growing up in Korea,” Nahm said.
“Perhaps the next generation will produce winners of Nobel
prizes in science, which Koreans consider as the last proof of Korea’s arrival
on the world stage.”
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