After seven years of research, a team of scientists led by Nicholas Nigretti published ground-breaking findings on the inner workings of the notorious bacterial strain known as Campylobacter jejuni. Its name may not be as well-known as Salmonella or E. coli, but its effects are just as severe, if not worse.
What is Campylobacter Jejuni?
Campylobacteriosis, or Campylobacter infection, is one of the leading causes of bloody diarrhea worldwide. Symptoms of Campylobacter infection also include nausea, vomiting, and stomach cramps. Bloody diarrhea occurs when the bacteria have successfully infiltrated the intestinal cell wall.
How Serious is Campylobacter Infection?
The Center for Disease Control cites campylobacter infection as the leading cause of diarrheal illness in the United States alone. An estimated 400-500 million people are infected with Campylobacter yearly, with cases rising in the summer.
Irritable bowel syndrome and arthritis can follow a C. jejuni infection, especially in those with weakened immune systems. In severely immunocompromised patients, bacteria can spread to the bloodstream and may become life-threatening.
Stunted growth, particularly in impoverished children from developing countries, sometimes happens due to C. jejuni infection. In extreme cases, campylobacteriosis may lead to the development of Guillain-Barré syndrome (GBS), an autoimmune disorder that affects the nerves. GBS may cause muscle weakness in the legs and may last from a few weeks up to several years. An estimated 1 in every 1,000 people infected with Campylobacter develop GBS. Severe cases have resulted in paralysis and even death.
Antibiotic resistance has led the World Health Organization to declare Campylobacter infection a severe threat.
How Can You Get Infected with Campylobacter?
Campylobacter can quickly colonize different animals intended for human consumption, such as chickens, cows, and turkeys. These animals show no symptoms when infected, making detection difficult without proper testing.
Contaminated animal feces may also reach fruits, vegetables, and natural water sources. This is an excellent example of why you should thoroughly wash your fruits and veggies (and your hands, of course). Though Campylobacter isn’t spread through human-to-human contact, it doesn’t take much to contract an infection.
How Does Campylobacter Infect Humans?
Campylobacter bacteria secrete a protein known as CiaD. This protein allows the bacteria to infiltrate host cells by binding to a specific protein, which starts a chain reaction that alters normal cell processes.
Apart from causing nauseating physical effects, hiding inside the intestinal lining allows the bacteria to shield itself from the host’s immune system. Scientists have understood that C. jejuni bacteria need to get inside the host cell to cause disease, but they are unclear on how this process works. The results from this study will allow researchers to attack the bacteria from a different perspective, hopefully leading to a dramatic decrease in infection rates worldwide.
A Win for Science
The story began when Konkel Lab discovered in 1999 that the bacterium C. Jejuni secretes proteins. Scientific curiosity would lead to another breakthrough ten years later when a postdoctoral fellow named Jeffrey Christiansen first identified the CiaD protein. The next big step happened in 2013 when C. Jejuni was found to transport the CiaD proteins to the host cells.
Researchers then asked why this specific protein would need to be in this same cell. What would it mean for the host?
The National Institutes of Health graciously funded the study through a $1.9 million grant. Despite the pandemic, the researchers pressed on and finished the study in February this year. Lead researcher Negretti speculates that processes that affect the cell could affect the intestinal cell’s ability to absorb nutrients. This finding may lead to further understanding of how the bacteria causes growth and nerve problems.
Nature is truly fascinating in the way it orchestrates certain events. This study focused on the actions of one particular protein from one type of bacteria. We can only imagine what more there is to discover other bacterial proteins and how much they affect our lives.
Born and raised in Oklahoma, Brianna now hangs her hat in the mountains of the East Coast. She is an Alumna of Liberty University with a degree in Criminal Justice and is a multiple time recipient of the Dean’s list award. As one of the senior journalists of Top Doctor Magazine, she has had the pleasure of interviewing many doctors and professionals about their fields of expertise.