Periodontology, Research

ASOD Researchers Find Biomarker That Captures Immune, Microbial Activities in One Measurement

Adam Lietzan

UNC Adams School of Dentistry researchers have described a biomarker for periodontitis (gum disease) that tracks with disease severity and may help identify at-risk individuals for early clinical intervention.

Adam Lietzan, PhD, DMD, MS, Assistant Professor in the Division of Oral and Craniofacial Health Sciences, along with Matthew Redinbo, PhD, Kenan Distinguished Professor in the Department of Chemistry, formed an interdisciplinary team with the aim of identifying a biomarker for gum disease that simultaneously captures both immune and microbial activities.

“The onset of gum disease is multifactorial, but the underlying etiology involves a microbial challenge and subsequent immune response. We were looking for a biomarker that could capture both the immune and microbial activities in a single clinical measurement – a critical concept that has eluded our field,” Lietzan said.

Recognizing that beta-glucuronidase (GUS) activity is a proxy for immune cell activation, the team hypothesized that oral microbes may also contain GUS orthologs. By searching the Human Oral Microbiome Database, the researchers identified 53 unique orthologs of GUS from oral bacteria, many of which stem from pathogenic oral microbes.

graphical image of periodontology research

“Human GUS activity is needed to maintain healthy tissues including the gums. However, we found that GUS enzymes from pathogenic oral microbes are significantly more efficient at processing components found in human tissues,” Lietzan said.

Using clinical samples collected from individuals with gum disease, the research team demonstrated that GUS activity increases with disease severity and that a significant portion of this activity derives from oral microbes.

“By using a specific inhibitor against microbial GUS, we were able to show that GUS activity from clinical samples is a combination of both the human GUS, likely from immune cells and microbial GUS from bacteria. This is the only biomarker to date that can do this,” he said.

With this knowledge in hand, oral health care providers may have better insight into gum disease progression and severity, possibly by using an inexpensive chairside test.

“Introducing an inexpensive and simple chairside test for dentists to monitor gum disease activity may help us stratify patients in need of more advanced gum treatment,” Lietzan said. “We too often identify patients with gum disease after they’ve shown signs of bone loss around their teeth – this unique biomarker may help us intervene earlier.”

Lietzan said the research also lends itself to future studies and hopes to expand this work into a larger clinical study.

“Our plan is to expand our studies into a larger patient population. We’d like to capture a wider range of gum disease severities to us help validate the utility of this biomarker. Our initial findings were promising, but more work is needed before incorporating this biomarker into everyday clinical practice.”

The study’s findings were published May 5 in the journal Science Advances.