For the first time, it has been discovered that neutrophils exist in
the spleen without there being an infection. This important finding made
by the research group on the Biology of B Cells of IMIM (Hospital del
Mar Research Institute) in collaboration with researchers from Mount
Sinai in New York, has also made it possible to determine that these
neutrophils have an immunoregulating role.
Neutrophils are the so-called cleaning cells, since they are the
first cells to migrate to a place with an infection and inflammation to
destroy the pathogens. Until now, scientific literature had considered
neutrophils essentially as lowly qualified soldiers that simply limited
the expansion of an infection, as a first action to pave the way for
other cells of the immune system in charge of eradicating the infection
permanently.
"This study has revealed that neutrophils are found in the spleen
without there being an infection, contributing totally new knowledge in
the field of biology" explains Andrea Cerutti, the coordinator of the
research group on the Biology of B Cells of IMIM, a professor at ICREA
and the last signatory of the article.
Researchers noticed that the existence of neutrophils in the
spleen started when the fetus is developing, even when there is no
infectious process involved; this was not known in scientific
literature. The study was expanded to people of different ages and other
mammals. Detecting the presence of neutrophils in the spleen suggested
that these played a different role in the spleen to the one usually
given to them.
The neutrophils in the spleen are located around B lymphocytes to
help their activation and offer a first rapid response when there are
pathogens. "through several different experimental approaches we have
proven that neutrophils in the spleen acquire the ability to interact
with B cells or B lymphocytes, inducing the production of antibodies, a
role that lymphocytes circulating in blood are not able to do" states
Irene Puga, researcher of the IMIM and a signatory of this article.
This finding improves the understanding of the mechanisms with
which our immune system protects us against an infection, an essential
requirement to better control all pathologies linked to it. Also, when
faced with certain diseases, such as neutropenia (or a numeric
deficiency of neutrophils), it will become necessary to study not only
the deficiency of neturophils, but also how this affects the production
of antibodies.
This work opens the door to therapies which are geared at, and
more affective against, different pathogens, for example, to develop
vaccines to increase the capacity of neutrophils in the spleen so as to
have an incidence on the production of antibodies by type B lymphocytes.