Samba village, Yako Province, Burkina Faso: Malnourished children eat nutritious porridge after health workers' demonstration of the method.Credit: Mike Goldwater/Alamy Stock Photo
A new study published in Science Translational Medicine has found how the body responds to environmental enteropathy (EE), damage to the small intestine, which is highly prevalent in low- and middle-income countries.
The condition is a poorly defined state of intestinal inflammation occurring in people who are continually exposed to poor sanitation and hygiene. EE is considered a cause of malnutrition, oral vaccine failure, and impaired cognitive development in children from low-income countries, especially across Africa.
“There are millions of kids with this disorder. Really good studies and systematic analyses over the last 10 years have consistently shown that you can take children with stunting, give them additional nutrients, and they do not respond,” says Paul Kelly, from the Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia, who is a senior author of the paper.
Kelly explains that of children who are given nutritional supplements to counteract stunting, only 15% make growth gains. The researchers attribute this to their inability to process the nutrients correctly. The team mapped the cellular and molecular correlates of environmental enteropathy by performing high-throughput, single-cell RNA sequencing on 33 small intestinal biopsies from 11 adults with the condition in Lusaka, Zambia. Of these participants, eight were HIV-negative while three were HIV-positive). Their profiles were compared with that of six adults in Boston, USA, and two adults in Durban, South Africa, that did not have the condition.
The study identified common pathways that are associated with the disease and cell-type contribution to EE severity. The team reported that while immune cells are active, the response found in the condition was different from what is expected during a normal response as shown in the varied response from the epithelial cells.
“Typically, if the immune cells are active, there should be a whole bunch of regenerative responses. All the stem cells should try to make more of themselves and try to rebuild. They should be trying to fix things. But this was not what we found in the biopsy specimens,” Thomas Wallach, co-senior author of the paper, from the department of pediatrics, SUNY Downstate Health Sciences University, in New York, United States, tells Nature Africa.
This work, Wallach says, presents an opportunity for targeted research on what drives that change — specifically focusing on why such a unique response is seen from the intestinal stem cells. “We can try to fix that in particular and have another avenue of trying to treat this with something fairly non-invasive, inexpensive and very, very safe,” he added.
Regarding the reproducibility of the study’s findings if applied elsewhere, Wallach concedes that pathogens and food sources are very different around the world, and in various areas where EE is prevalent. “We’ve got to start somewhere, and this is a great and a really exciting starting point,” he says.
