Saving lives by making pneumonia vaccine affordable

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."