A study published in the February issue of the new journal Science Advances is perhaps the first to identify distinct stages of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Importantly, it demonstrates some immune signatures early in the course of ME/CFS that are not present in subjects with longer duration of illness.
Although efforts were made to identify a specific biological pattern, there are no trustful biomarkers or validated laboratory test for the diagnosis or management of ME/CSF.
In an attempt to discover reliable biological markers related to ME/CSF, Mady Hornig and colleagues from the Center for Infection and Immunity at the Columbia University’s Mailman School of Public Health, New York, USA determined the levels of 51 cytokines and chemokines in ME/ CSF patients from two large multicenter studies.
In the Science Advances study these authors reported specific cytokine patterns during the early phase (≤3 years) of ME/CSF, including high plasma levels of IL-1α, IL-1RA, IL-4, IL-8, IL-12p40, IL-13, IL-17A, TNF-α and MCP1. Of particular interest was the marked association of interferon (IFN)-γ with the early phase of illness that was detected through logistic regression modeling.
Of note, IFN- γ is known to modulate brain’s neuronal activity, affecting mood, sleep, temperature regulation and the endocrine system. Also, high levels of IFN- γ can lead to depressive states and physical tiredness similar to the observed in ME/CSF patients, due to the degradation of tryptophan and reducing brain levels of serotonin and melatonin (M Maes et al., 2007; AH Miller et al., 2013).
The Hornig et al. study is consistent with the hypothesis of a viral trigger of this condition and, as discussed by the Center for Infection and Immunity Website at Columbia University, it may also substantiate the idea that ME/CFS reflects an infectious ‘hit-and-run’event. Overall; the study indicates that ME/CSF is an immunological and not a psychological disease.
Early in the course of chronic fatigue syndrome, as determined by this study, specific immune profiles may have important implications for early diagnosis. This may also suggest new therapeutic and immunomodulatory interventions, which in this condition may be transient or time-limited.
Source: Science Advances, 2015, 1, no1:e1400121. DOI: 10.1126/sciadv.140012
Read More: Science Advances
Related story you may like: Meningeal interferon-γ and social behavior
Interferon and the Central Nervous System
Hyperactive Interferon Choroid Plexus Aging and Cognitive Dysfunction
Anxiety Linked to High IFN-γ and TNF-α