Immunoglobulin free light chains in saliva: a potential marker for disease activity in multiple sclerosis

Abstract

A new procedure was developed and applied to study immunoglobulin free light chains (FLC) in saliva of healthy subjects and patients with multiple sclerosis (MS). The procedure was based on a Western blot analysis for detection and semiquantitative evaluation of monomeric and dimeric FLCs. The FLC indices accounting for the total FLC levels and for the monomer/dimer ratios of κ and λ FLC were calculated, and the cut-off values of the FLC indices were determined to distinguish healthy state from MS disease. The obtained FLC index values were statistically different in the saliva of three groups: active MS patients, MS patients in remission and healthy subjects groups. Our FLC monomer-dimer analysis allowed differentiation between healthy state and active MS with specificity of 100% and a sensitivity of 88·5%. The developed technique may serve as a new non-invasive complementary tool to evaluate the disease state by differentiating active MS from remission with sensitivity of 89% and specificity of 80%.

Salivary Biomarkers: Future Approaches for Early Diagnosis of Neurodegenerative Diseases

“…Conversely, the RR-MS in the relapsing phase showed levels of FLCs similar to the HC subjects. In conclusion, the salivary monomer-dimer FLC analysis could be used for MS diagnosis and to differentiate the relapsing phase versus the remitting phase [84].…”

The Increasing Role of Kappa Free Light Chains in the Diagnosis of Multiple Sclerosis

“…Totolian et al investigated the concentrations of KFLC and LFLC in lacrimal fluid and saliva and found increased concentrations of KFLC compared with the controls [115]. Lotan et al and Kaplan et al determined monomer and dimer isoforms of FLC in saliva using a Western blot assay [116,117]. Both studies revealed that calculated saliva FLC index values might be a useful biomarker to differentiate between a healthy state and active MS, with a sensitivity of about 90% [116,117].…”

“…Lotan et al and Kaplan et al determined monomer and dimer isoforms of FLC in saliva using a Western blot assay [116,117]. Both studies revealed that calculated saliva FLC index values might be a useful biomarker to differentiate between a healthy state and active MS, with a sensitivity of about 90% [116,117]. Conclusively, the authors emphasized that the analysis of non-invasively gained body fluids could be of importance in the biochemical follow-up of patients or the therapeutic monitoring as the inflammatory disease activity and immunosuppressive treatment with corticosteroids influenced the concentration of KFLC in urine and saliva [63,[111][112][113][114][115][116][117].…”

“…Both studies revealed that calculated saliva FLC index values might be a useful biomarker to differentiate between a healthy state and active MS, with a sensitivity of about 90% [116,117]. Conclusively, the authors emphasized that the analysis of non-invasively gained body fluids could be of importance in the biochemical follow-up of patients or the therapeutic monitoring as the inflammatory disease activity and immunosuppressive treatment with corticosteroids influenced the concentration of KFLC in urine and saliva [63,[111][112][113][114][115][116][117]. However, theoretical considerations and the low number of reports undermine the role of FLC in body fluids other than CSF and serum in the diagnostic work-up of MS patients.…”

Diagnostic utility of kappa free light chains in multiple sclerosis

“…This point of view is supported by the reported changes in mucosal immunity of MS patients, including: increased number of immunoreactive cells in the saliva [24,25]; impairment of mucosal barrier of the gut [26]; presence of oligoclonal immunoglobulin bands and increased amounts of IgG and IgA in the tears [27][28][29]. Although these findings raise a hope that FLC analysis of the more easily accessible bodily fluids may be diagnostically useful in MS, this issue has been studied only by few authors and needs further confirmation and investigation [30,31].…”