All human beings have an innate immune system, made up of different cells in charge of executing the primary response of our organism against the threat of an external agent. Within these cells, there are neutrophils, which are studied by Dr. Nalú Navarro Álvarez for their possible role on the development of post-hepatectomy liver failure.

Neutrophils are the first cells that go to any site of infection or damage in the human body. These cells are released from the bone marrow into the circulation where, through an orderly and intriguing process, will be activated to locate, attack and destroy the potential intruder. This is how we know the neutrophils and we identify their function,” said Dr. Nalú Navarro, PhD in cellular therapy and regenerative medicine.

In this sense, the researcher of the National Institute of Medical Sciences and Nutrition Salvador Zubirán is focused on establishing the changes in the functions of neutrophils, when these are activated after a liver resection (removal of a segment of the liver).

Why are cells activated?

According to the specialist, a cell is activated to respond to a certain need of the body; after executing its function, the cell must return to its inactive state or be eliminated.

The general idea is that when a cell perceives a threat it activates because it must respond. When the threat disappears, the cell should return to its native state or, in the case of neutrophils, be eliminated so that they don’t continue secreting substances that could be harmful to the organism itself,” said Dr. Nalú Navarro.

Through tests in animal models, Nalú Navarro found that the individuals that developed liver failure after a hepatectomy showed high levels of activated neutrophils in the liver and peripheral blood.

To know this information, neutrophils in the peripheral blood and in the liver of the surgically treated models were analyzed by flow cytometry, a technique used to obtain information on cell populations.

In previous studies in mice, we detected a marker in the membrane of neutrophils that indicates its activation state. In our current study, we observed that in the neutrophils of the animals that did regenerate their liver after resection, this marker is expressed transiently; while the neutrophils of the animals that developed post-hepatectomy liver failure did not ‘turn off’ this marker,” she said.

So far, the researchers of this project have only performed tests on animal models surgically treated; however, they intend to develop a chemical-induced liver damage model.

With the chemical-induced liver damage model, we would try to extrapolate what would happen in a person with acetaminophen (paracetamol) poisoning, a very common cause of liver failure in our country,” he said.

How would it benefit patients?

The results of this research will be used to analyze the characteristics of neutrophils within the environment of liver failure, with the ultimate goal of identifying whether these cells undergo changes in their gene expression during the disease.

The first thing we need is to determine the functions of neutrophils in the specific case of liver failure, that is, what substances they secrete, what markers are in their membrane and what gene expression changes they have, in order to understand their role in this condition. If we can identify these characteristics with precision, we could use them as possible biomarkers in the development of this disease,” said Dr. Nalú Navarro.

On the other hand, knowing the particularities of neutrophils during liver failure would allow experts to develop a therapy or medication that would stop the function of this cell, a possible cause of this condition.

The innate immune system is made up of many cells. We have to achieve identify meticulously the specific role of each of these cells in liver regeneration. In our study, we have also observed that there are other cell populations that disappear in the case of liver failure, so we intend to continue studying each of the cells that make up this system, because there is still much to discover,” the researcher concluded.

 

Source: Agencia Informativa CONACYT