The widespread, pathogenic microbe Staphylococcus aureus can colonize the skin and mucous membranes throughout the body, particularly the vagina and gastrointestinal tract. A virulent strain of the bacterium produces proteins that trigger toxic shock syndrome (TSS), a disease characterized by the quick onset of fever, a telltale rash, and, without treatment, multi organ failure.
Probiotics may help prevent the disease before the cytokine cascade ever begins. A study reports that strains of 2 bacteria, Lactobacillus acidophilus and Lacticaseibacillus rhamnosus, successfully inhibited the production of the superantigens that cause TSS, in lab experiments.
A combination of the 2 could both prevent growth and inhibit the immune response. “It’s kind of a double whammy against S. aureus,” said microbiologist Patrick Schlievert, Ph.D. “If any toxin is made, the probiotics still prevent inflammation.”
The new work, he said, was motivated by observations made during an earlier study. A few years ago, he and his colleagues recruited 205 women to test whether a novel molecular mixture, when added to tampons, would inhibit pathogenic bacteria. That molecule proved effective against E. coli and other pathogens, but the researchers noticed an unexpected consequence.
“Some of the women in the treatment group had this tremendous growth of Lactobacilli,” Schlievert said.
Further studies revealed that 9 of those women were colonized with only L. crispatus and no other bacteria. In microbiology research, Schlievert said, colonization by a single bacterium is often regarded as unhealthy. In this case, however, it offered an effective action against pathogenic S. aureus.
Lactobacillus bacteria have already been shown to be safe, Schlievert said, and the new work suggests that treatment with L. crispatus alone, or L. acidophilus and L. rhamnosus in combination, could dramatically reduce the risk of TSS in vulnerable populations. Strains of S. aureus can also cause enterocolitis, a life-threatening immune response in the gut. Probiotics may also help reduce the production of dangerous proteins for that disease, said Schlievert.
In ongoing and future work, Schlievert and his team are investigating how to use probiotics to prevent skin staph infections. Schlievert sees probiotics as a promising way to prevent complications. “If we can improve their lives by using this approach, that would be wonderful.”
Patrick M. Schlievert, Adriana V. Gaitán, Samuel H. Kilgore, Amy L. Roe, Johanna Maukonen, Liisa Lehtoranta, Donald Y. M. Leung, Daniel S. Marsman. Inhibition of Toxic Shock Syndrome-Associated Staphylococcus aureus by Probiotic Lactobacilli. Microbiology Spectrum, 2023; DOI: 10.1128/spectrum.01735-23
American Society for Microbiology. “Probiotic combo stops bacteria that cause toxic shock syndrome.” ScienceDaily. ScienceDaily, 21 July 2023. <www.sciencedaily.com/releases/2023/07/230721113221.htm>.
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