A study published in Beneficial Microbes and sponsored by DuPont Nutrition & Health, Madison, WI, and the University of Virginia demonstrated the role of probiotic supplementation to maintain healthy respiratory immune function. The results of a randomized, double-blind, placebo controlled study investigating the effect probiotics had on the immune response in healthy, rhinovirus-challenged adult human subjects suggest that ingestion of Bl-04 at a dose of 2 billion CFU per day has an effect on the inflammatory response to rhinovirus infection. The common cold is one of the most prevalent diseases globally and is typically caused by rhinovirus infection.

A specific probiotic strain Bifidobacterium lactis Bl-04 (Bl-04), available only from DuPont, was consumed by participants for one month, and innate immune response and presence of rhinovirus in the nostrils was investigated. The virus and the immune markers were analyzed from nasal washes, collected before and after Bl-04 supplementation and for 5 days after the introduction of the rhinovirus challenge. Compared to placebo, the probiotic supplement, commercially available HOWARU Protect Adult, had an effect on the presence of the virus in the nostrils, demonstrated by a decreased amount of rhinovirus in nasal washes during infection and a lower proportion of study participants with rhinovirus detected in nasal washes.   

“The effects observed in this short-term, well-controlled study were modest and may only partially explain reduction in illness reported in the natural setting,” said Dr. Ron Turner, MD, professor of Pediatrics, University of Virginia School of Medicine. “However, the results do suggest the utility of further investigations of the effect of specific probiotics on innate immune function in the human host.”

This study approach, known as a challenge model, is unique in that it provides an opportunity to characterize the interaction between the infection and host responses under controlled conditions in human volunteers with use of probiotics. The results of the new study suggest that ingestion of Bl-04 may modify the innate immune system response following supplementation and the inflammatory response in the nose following rhinovirus infection.

Probiotics have induced expression of antiviral responses in preclinical cell and animal models. Moreover, Bl-04 has been shown to reduce the risk of upper respiratory illness episodes in a human clinical trial over a 5-month study time.

“DuPont has a strong portfolio of clinically documented probiotics for immune health including HOWARU Protect EarlyLife for pregnant mothers and infants, HOWARU Protect Kids, HOWARU Protect Sport, HOWARU Protect Senior, and, of course, HOWARU Protect Adult. We are committed to continuing to clinically research probiotics for immune health, digestive health and emerging health areas,” said Megan DeStefano, global probiotics marketing leader, DuPont Nutrition & Health. “HOWARU Protect Adult (Bl-04) is one of the best documented probiotics for immune health in the world, and we are proud to be able to deliver an efficacious and stable probiotic to the industry so consumers can benefit.”