Most people think little about their appendix, and that's only natural, because the function of the appendix has been considered unknown — until now. New research supports that our appendixes might actually be useful after all, and doctors may soon be changing their tune about this neglected organ. The appendix, which looks like a slim tube measuring between two and four inches long, sits in our lower right abdomen. It was originally thought to be vestigial — a part of the body that evolution forgot. Popular belief was that this leftover organ was originally part of a fermenting chamber in our gut, used to processed uncooked foods and grass (similar to a cow). Today, if the appendix causes too much trouble, it becomes inflamed — even in mild cases of appendicitis, doctors will usually remove it as a preventative measure. Even if removal isn't imperative, and the infection can be treated by non-surgical options like antibiotics, those remain largely unexplored. The appendix, like our long forgotten tonsils, gets no love.
A study published in Nature Immunology in November suggests that this underrated organ might actually be key for maintaining immune cells useful for fighting infections in the gut. You go appendix! Teams from Melbourne’s Walter and Eliza Hall Institute of Medical Research and the Centre d’Immunologie de Marseille-Luminy, France collaborated to explore "how ILC3s (one group of ILCs) function during and after a gut infection — particularly how they altered immune protection," explains Mental_Floss. Innate lymphoid cells (ILCs) are strong immune cells, important for combatting bacterial infection especially in those with immune systems which are damaged or weakened. ILCs are so hardy that they are able to can even withstand chemotherapy. Gabrielle Belz, researcher and co-author of the study, explains that ILCs are found all over the body, “underlying all the body’s surfaces, including the skin, the lungs, the gut, and the reproductive tract, and play a very important and broad role in protecting the body from infections and responses to environmental insults.”
In the study, researchers infected mice with a pathogen that infects the cecum first. The cecum is pouch at the beginning of the large intestine, which is connected to the appendix, and houses a large amount of ILC3 immune cells. They then removed the ILC3s, causing inflammation of the nearby colon and shrinkage of the cecum pouch. Belz confirmed the link to the appendix, saying, "Thus, surprisingly, altering the balance of immune cells significantly affected what was happening in the cecum, suggesting that a similar effect might occur in humans in the appendix."
This corroborates research by Duke University Medical Center from 2007, which proposed that the appendix acts as a "safe house" for bacteria useful to the human gut, especially in cases of diarrhea and infection. "Once the bowel contents have left the body, the good bacteria hidden away in the appendix can emerge and repopulate the lining of the intestine before more harmful bacteria can take up residence," posits William Parker, PhD, who has examined the bacterial interactions in the gut for over a decade and co-authored the Duke University analysis.
“It seems likely that [the appendix] is an integral part of the immune system," Belz adds, and “This highlights that simply disposing of this organ may not always be in our best interests.”
It now seems the status of the appendix has gone from superfluous to super! Talk about a tummy ache!