Blood, Spit, and Peers
IPR faculty offer biomarker instruction and establish community of scholars

Spring 2007, Volume 29, Number 1

Graciela Teruel of the Universidad Iberoamericana obtains a blood spot from fellow participant Luis Rubalcava of UCLA.

In theory, it sounded simple: Prick the subject’s finger, extract a drop of blood, and then position the drop in the middle of the circle on the filter paper. However, the 29 purple-gloved academics, researchers, and graduate students quickly discovered that obtaining a dried blood spot—which can later be transformed into whole blood for analysis—is not as easy as it looks.

There was the social scientist with hands so cold that only a pin drop of blood could be drawn; the graduate student who blew on a sample and contaminated it; those too squeamish to have their finger pricked. This was one of several hands-on exercises at a biomarker institute last June run by Cells to Society (C2S): The Center on Social Disparities and Health. It will take place again this June. C2S is housed within the Institute for Policy Research and directed by IPR Faculty Fellow Lindsay Chase-Lansdale, professor of human development and social policy.

Three IPR and C2S faculty members organized the three-day summer institute: Thomas McDade, associate professor of anthropology; Emma Adam, assistant professor of human development and social policy; and Christopher Kuzawa, assistant professor of anthropology. All are specialists in the emerging use of biomarkers, which allow scientists to link biological processes to broader social, cultural, and economic environments.

The institute walked participants through the entire process of biomarker data acquisition, including collection of samples in the field, analysis in the lab, interpretation of results, theory, and practical, hands-on exercises. It had two goals: educating the participants in state-of-the-art methods for integrating biomarkers into population-based, social science research and building a community of scholars around these objective measures of health.

“We are training the next generation of scholars to study how environmental factors ‘get under the skin’ to shape human development and health,” said McDade, C2S’s associate director.

Historically, population health research has relied primarily on self-reports of health, said McDade. Yet this is tricky because “what you think of your health and your actual state of health might differ across generations, cultures, and ethnicities,” he pointed out. Self-reports can be tainted by a host of factors, including faulty recall, language ability, and miscommunication, among others.

“It’s hard to get objective measures of health outside of the clinic, so this is where minimally-invasive biomarker methods hold a lot of promise,” McDade continued. These methods also have the advantage of being more cost effective, easier to use in real-life situations, and less invasive than traditional gauges of health typically used in clinical settings.

In addition to the session on dried blood spots, the 29 participants also learned about the strengths and weaknesses of using saliva, DNA, and other biomarker methodologies to measure stress, cardiovascular function, immune function, and nutritional status in large-scale population surveys. The participants came from academic, research, and government institutions across the United States and Mexico.

Attendees such as Graciela Teruel, who is a professor at the Universidad Iberoamericana, are already working on large-scale surveys. She is also co-principal investigator of the Mexican Family Life Survey, a longitudinal panel survey with 34,000 participants in Mexico. She thinks that implementing biomarker methods will help to improve the third wave of the survey because of the difficulties in obtaining accurate health information from participants.

“Using dried blood spots will definitely help us to have not only more objective measures of health but also to link this information to either behaviors or past information about this particular individual,” Teruel said. She expects they will be especially informative as the study progresses to document the transition of Mexicans’ health over time.

Though they have many implications for large-scale population studies, biomarkers are also viable for much smaller studies. Social psychologist Jennifer Richeson, an IPR faculty fellow, typically relies on one-on-one interactions and cognitive testing for groups of people to measure intergroup relations in her work.

“Using salivary cortisol, for example, allows you to obtain information on a person’s stress levels without undermining the interaction, without having to stop the interaction to put on a blood pressure cuff,” Richeson said. She is associate professor of psychology and African American studies.

Acquiring a better understanding of these cutting-edge techniques also brought Michael Spittel, a program officer in the Demographic and Behavioral Sciences Branch at the National Institutes of Health, to the institute. He oversees a grant portfolio of mortality and morbidity projects.

Spittel says more demographers are starting to employ biomarkers in their health research. Thus, it is important to have exposure to the methods/techniques they will be using.

“It is humbling to see how much work and technical expertise are required to collect and analyze biomarker data,” Spittel said.

Finding out how much error could be involved in obtaining blood-spot samples and that a sizeable staff is required to process the samples correctly was an eye-opener for him.

“I learned a tremendous amount,” Spittel said. “Observing how biomarker data is collected while hearing from some of the leading experts in this field was a valuable experience.”

For more about the next C2S Biomarker Institute, see www.northwestern.edu/ipr/c2s/events/biomarkers.html.