infection susceptibility – American ME and CFS Society

Abstract:

Chronic fatigue syndrome (CFS) is a severe disease characterized by various symptoms of immune dysfunction. CFS onset is typically with an infection and many patients suffer from frequently recurrent viral or bacterial infections. Immunoglobulin and mannose binding lectin (MBL) deficiency are frequent causes for increased susceptibility to infections.

In this study we retrospectively analysed 300 patients with CFS for immunoglobulin and MBL levels, and B-cell subset frequencies. 25% of the CFS patients had decreased serum levels of at least one antibody class or subclass with IgG3 and IgG4 subclass deficiencies as most common phenotypes.

However, we found elevated immunoglobulin levels with an excess of IgM and IgG2 in particular in another 25% of patients. No major alteration in numbers of B cells and B-cell subsets was seen. Deficiency of MBL was found in 15% of the CFS patients in contrast to 6% in a historical control group. In a 2nd cohort of 168 patients similar frequencies of IgG subclass and MBL deficiency were found. Thus, humoral immune defects are frequent in CFS patients and are associated with infections of the respiratory tract.

Source: Guenther S, Loebel M, Mooslechner AA, Knops M, Hanitsch LG, Grabowski P, Wittke K, Meisel C, Unterwalder N, Volk HD, Scheibenbogen C. Frequent IgG subclass and mannose binding lectin deficiency in patients with chronic fatigue syndrome. Hum Immunol. 2015 Oct;76(10):729-35. doi: 10.1016/j.humimm.2015.09.028. Epub 2015 Sep 30. https://www.ncbi.nlm.nih.gov/pubmed/26429318

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is considered as a neuroimmunological disease but the etiology and pathophysiology is poorly understood. Patients suffer from sustained exhaustion, cognitive impairment and an increased sensitivity to pain and sensory stimuli. A subset of patients has frequent respiratory tract infections (RRTI). Dysregulation of the sympathetic nervous system and an association with genetic variations in the catechol-O-methyltransferase (COMT) and glucocorticoid receptor genes influencing sympathetic and glucocorticoid metabolism were reported in CFS. Here, we analyzed the prevalence of SNPs of COMT and glucocorticoid receptor-associated genes in CFS patients and correlated them to immunoglobulin levels and susceptibility to RRTI.

METHODS: We analyzed blood cells of 74 CFS patients and 76 healthy controls for polymorphisms in COMT, FKBP5 and CRHR1 by allelic discrimination PCR. Serum immunoglobulins were determined by immunoturbidimetric technique, cortisol levels by ECLIA.

RESULTS: Contrary to previous reports, we found no difference between CFS patients and healthy controls in the prevalence of SNPs for COMT, FKBP5 and CRHR1. In patients with the Met/Met variant of COMT rs4680 we observed enhanced cortisol levels providing evidence for its functional relevance. Both enhanced IgE and diminished IgG3 levels and an increased susceptibility to RRTI were observed in CFS patients with the Met/Met variant. Such an association was not observed in 68 non-CFS patients with RRTI.

CONCLUSION: Our results indicate a relationship of COMT polymorphism rs4680 with immune dysregulation in CFS providing a potential link for the association between stress and infection susceptibility in CFS.

Source: Löbel M, Mooslechner AA, Bauer S, Günther S, Letsch A, Hanitsch LG, Grabowski P, Meisel C, Volk HD, Scheibenbogen C. Polymorphism in COMT is associated with IgG3 subclass level and susceptibility to infection in patients with chronic fatigue syndrome. J Transl Med. 2015 Aug 14;13:264. doi: 10.1186/s12967-015-0628-4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4536662/ (Full article)