Ricardo Ernesto Ramírez-Orozco , Elena Franco Robles , Victoriano Pérez Vázquez , Joel Ramírez Emiliano , Marco Antonio Hernández Luna , Sergio López Briones
J. Microbiol. 2018;56(9):673-682. Published online August 23, 2018
Obesity is a chronic disease associated with different metabolic
diseases as well as alterations in immune cell function.
It is characterized by a chronic systemic low grade inflammation.
There are several studies demonstrating the influence
of obesity on the impaired immune response to infection.
However, it is not completely clear whether the obese environment
influences the development or maintenance of the
immune response against infections. The aim of this study
was to determine how obesity induced by a high-fat diet affects
the immune response to an early oral Salmonella infection.
Four groups of mice were kept in separate cages. Two of
these designated as controls, fed with a normal diet; whereas
other two groups were fed with a high fat diet for 10 weeks.
Some mice were used for Salmonella oral infection. After 7
days of oral infection with S. Thypimurium the proportions
of spleen cell subsets expressing activation markers in normal
diet and HFD obese mice were stained with monoclonal
antibodies and analyzed by flow cytometry. Also, mRNA
levels of different cytokines were quantified by RT-PCR. It
was found that obesity affects the function of the immune
system against an early oral Salmonella infection, decreasing
NK cells, altering the expression of activation molecules as
well as cytokines mRNA levels. Interestingly, the expression
some activation molecules on T lymphocytes was reestablished
after Salmonella infection, but not the CD25 expression.
Immune alterations could lead to immunosuppression
or increased susceptibility to infections in HFD obese mice.