Source: Thailand Medical News Jan 22, 2020 4 years, 10 months, 2 weeks, 20 hours, 30 minutes ago
A new study from Karolinska Institutet in Sweden, published in the scientific journal
PNAS reports that
endogenous proteins that play a vital part in allergies and parasitic infection can prevent the
immune system from wrongly attacking the body and causing
inflamed joints, The medical researchers hope that the results will give rise to new drugs for
rheumatoid arthritis.
Typically, in protecting us against infections, our
immune systems are vital to our survival. Unfortunately,
immune cells can sometimes wrongly attack the body, resulting in what are called
autoimmune diseases. These diseases are often serious and affect some five per cent of the population. One example is
rheumatoid arthritis, in which the patient's
immune system attacks the joints, causing
inflammation and pain. If scientists are to develop better treatments for such patients, they need to understand in detail how immune cells are regulated.
Medical researchers at Karolinska Institutet have now discovered that certain proteins called
IL-4 and
IL-13 can play an important part in preventing
autoimmune attacks. The proteins, which are secreted by
immune cells in the presence of allergens or parasitic infections, influence the behaviour of a specific type of
immune cell called a neutrophil. Neutrophils are commonly the most abundant
immune cells found in the actively
inflamed joints of patients with
rheumatoid arthritis. They are particularly virulent against tissue since they can secrete various fairly non-specific tissue irritants.
Past research has shown that
IL-4 and
IL-13 can affect
arthritis in experimental models, but exactly how they do so has remained a mystery. The results of this latest study show that these
proteins prevent neutrophils from migrating into the
inflamed joint. The presence of
IL-4 or
IL-13 also stimulates an increase in neutrophil surface receptors which have an inhibiting effect on
joint inflammation.
Principal investigator Dr Fredrik Wermeling, Assistant Professor at the Department of Medicine, Karolinska Institutet (Solna) told
Thailand Medical News, "We will continue to study these mechanisms and hope that our work can contribute to the development of treatments for
rheumatoid arthritis."
;
The medical researchers used the CRISPR method to modify selected
immune-cell genes in order to understand how they affect cell behaviour. The use of the bacterial CRISPR system as a research method is one of the most significant scientific advances of the past decade.
Dr. Wermeling added, "The results we obtained using CRISPR were key to quickly understanding how the system under study is regulated. I have high hopes that the experimental use of CRISPR will be hugely important to our understanding of how
immune-cell behaviour is regulated, and that this can guide us in the development of new efficacious drugs."
Reference : Sudeepta Kumar Panda el al., "IL-4 controls activated neutrophil FcγR2b expression and migration into inflamed joints," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.1914186117