UC Davis researchers launch study of second-hand smoke and infection in infants, young children

July 2, 2009

(SACRAMENTO, Calif.) — Each year during the winter and spring, pediatricians’ offices are inundated by visits from very young children suffering from a variety of upper respiratory infections, ranging from rhino virus, or the common cold, to seasonal flu viruses, respiratory syncytial virus, or RSV, and pneumonia.

Researchers have known for some time that a higher proportion of these children live in households where smoking occurs. Studies have shown that, among children 2 and younger, the incidence of upper respiratory infection in households where smoking occurs is double that of households where children are not exposed to second-hand tobacco smoke.

Discovering why that is so — and why children exposed to second-hand smoke also appear to be more susceptible to secondary, opportunistic bacterial infections, like staph and strep — is the aim of an innovative new research study being launched this month by Kent Pinkerton, director of the UC Davis Center for Health and the Environment.

Pinkerton’s research will examine the effects of second-hand tobacco smoke on lung development and disease in mouse models, extending earlier studies in non-human primates on how exposure to second-hand smoke alters the development of the human immune system.

“Infant mice don’t initially appear to experience any baseline inflammatory response to second-hand smoke exposure,” said Pinkerton, who is also a professor in the Department of Pediatrics. “But what we have seen is that they appear to develop their metabolic function in a totally different fashion, and that alters their immune development.”

Pinkerton’s earlier research has focused on the relationship between in utero and infant exposure to second-hand tobacco smoke on lung development and the incidence of asthma and other chronic lung diseases. Joined in the research by postdoctoral fellow Lei Wang, the new study will focus on what Pinkerton called the “double hit” of second-hand smoke and its effects on primary viral and secondary bacterial infections in infants and young children.

“If you’re altering the conditions in the milieu of your lungs, you’re changing your immune status. That becomes important to how your immune system responds to anything in your environment, such as gasses like tobacco smoke, viruses and microorganisms like bacteria,” he said.

In addition to gaining a better understanding of the effects of second-hand tobacco smoke on infant lung development, Pinkerton said that the research could eventually yield insights into the causes of some adult-onset respiratory diseases.

“We’re pretty confident that some of the adult-onset diseases like chronic bronchitis or chronic obstructive pulmonary disease (COPD) may actually begin in your childhood,” Pinkerton said. “We usually think of asthma as being a childhood disease, but adults develop asthma, as well.”

“There are plenty of things to study and plenty of things we don’t know,” he said.

The study, “Lung Development, Tobacco Smoke, and Sensitivity to Infection,” is funded by a two-year, $250,000 innovation award from the Tobacco-Related Disease Research Program of the University of California Office of the President, which is funded by the state’s tobacco tax.

The aim of the awards is to provide investigators with seed funding to procure larger awards from organizations like the the National Institutes of Health (NIH). “And ultimately,” Pinkerton added, “to get people to stop smoking.”

UC Davis Children's Hospital is the Sacramento region's only comprehensive hospital for children. From primary care offices to specialty and intensive care clinics, pediatric experts provide compassionate care to more than 100,000 children each year and conduct research on causes and improved treatments for conditions such as autism, asthma, obesity, cancer and birth defects. For more information, visit the UC Davis Children's Hospital Web site.

Jan. 2, 2008

Gerd P. Pfeifer of the Beckman Research Institute of the City of Hope, past grantee and recently-retired TRDRP Scientific Advisory Committee member, was recently appointed to the first Lester M. and Irene C. Finkelstein Chair in Biology. Dr. Pfeifer is known for identifying the molecular link between cigarette smoking and lung cancer and recently received the largest of eight national grants from NIH as part of The Cancer Genome Atlas. The project develops technologies to detect and treat cancer. Congratulations Dr. Pfeifer!

GlaxoSmithKline is licensing nicotine vaccine technology developed by Kim Janda of the Scripps Research Institute. The company hopes to move the vaccine into clinical trials in the next 18 months.

Karen Messer, Dennis R. Trinidad, John P. Pierce, and their colleague Wael K. Al-Delaimy at the Moores Cancer Center at the University of California, San Diego have found that young adults are not only more likely than older adults to have tried to quit smoking, but are also more likely to quit successfully. Their paper “Smoking Cessation Rates in the United States: A Comparison of Young Adult and Older Smokers” was published in the Jan. 2, 2008 American Journal of Public Health.