Researchers at the University of Virginia’s school of medicine in Charlottesville, US have found that antibiotic use made neutrophils less effective in fighting infections and weakened the intestinal barrier against invading bugs. Researcher Koji Watanabe said that neutrophils play an important role as a first-line ‘innate immune response’ when foreign pathogens invade.
“We found that antibiotic disruption of the natural microbes in the gut prevented this from happening properly, leaving the gut susceptible to severe infection,” Watanabe added. The team used lab mice to determine how the decrease in natural intestinal flora might be worsening the disease.
They found that antibiotics disrupted the mice’s gut microbiomes, decreasing the activity of neutrophils and blocking these important white blood cells from responding when needed. This left the gut insufficiently protected. In essence, the gut’s guards did not respond when called and the invaders could march right in.
The disruption of the microbiome reduced the production of a key cellular protein vital to the barrier’s effectiveness. Another researcher Bill Petri stated that not to use antibiotics unless they are clearly needed. Unwise use of antibiotics not only increases the risk of multi-drug resistant bacteria and the risk of C. difficile infection but also impairs white blood cell function. The researchers suggested that the work could prove important in the efforts to develop a vaccine for amebic colitis, also known as amebiasis. The discovery might offer a way to enhance the effectiveness of such a vaccine.