It now seems clear that the patterns of disease in relapsing-remitting and secondary progressive MS are different.
In relapsing-remitting MS, it is the inflammation of the central nervous system that is more evident; by contrast, in secondary progressive MS, there is less inflammation but more degeneration of nerve cells.
Cytokines are major regulators of the immune system, and pro-inflammatory and anti-inflammatory cytokines are believed to play a major role in modulating the inflammation in MS.
Last December, the Journal of Neuroimmunology published a study from a team at the University of Pisa, Italy. They compared the levels and activity of cytokines in blood samples taken from people with relapsing-remitting and secondary progressive MS.
Sixty patients with MS (half with relapsing-remitting and half with primary progressive) were enrolled between July 2012 and December 2013.
Analysis showed significantly higher levels of pro-inflammatory cytokines and lower levels of immunosuppressant cytokines in relapsing-remitting than in secondary progressive MS.
These results underline the existence of differing cytokine levels and activity in relapsing-remitting and secondary progressive MS, with higher pro-inflammatory activity in the former.
However further studies are needed to better define the role of cytokines in the two types of MS and identify new biological markers in the management of MS.