Is Kir4.1 a target in MS?

Nerrant E et al. Is anti-KIR4.1 antibody a biomarker for multiple sclerosis? ECTRIMS 2013
Background: Multiple sclerosis (MS) is the most frequent chronic inflammatory disease of the central nervous system. Although demyelinating lesions formations are likely related to immune reactions, the identification of a target auto-antigene remained so far largely uncertain. Recently, the ATP-sensitive inward rectifying potassium channel, KIR4.1, was identified as a target of auto-antibodies in 46% of MS patients (Srivastava 2012). The aim of our study was to confirm these findings and to compare clinical characteristics of patients with and without anti-KIR4.1 antibody.
Methods: This prospective study included MS patients fulfilling 2010 McDonald criteria,patients with other neurologic diseases and bone marrow healthy donors as controls. The first step was to develop a specific and sensitive enzyme-linked immunosorbent assay (ELISA) for anti-KIR4.1 antibody evaluation using KIR4.183-120 peptide, as previously described. The threshold positivity was defined as 2 standard deviations (SD) above mean optical density (OD) of the control group. Primate brain and cerebellum sections were used for indirect immunofluorescence analysis. Clinical data were collected independently.
Results: From October 2012 to March 2013, 45 controls, 20 patients with OND and 253 MS patients were consecutively included. Anti-KIR4.1 Ab is found in 2/45 (4.4%) in controls versus 2/20 (10.0%) in patients with OND and 19/253 (7.5%) in MS patients.
Discussion: We confirm the presence of anti-KIR4.1 Ab in 7.5% of MS patients. However, the sensitivity and specificity of
anti-KIR4.1 Ab in MS appear much lower in our study than previously described. Our results suggest that anti-KIR4.1 Ab is not a suitable biomarker for MS. 


Maybe could not duplicate. The original paper indicated over 45% of MSers had this antibody and not in healthly people. 
This currently study suggests a lot less than that and questions the original data. 

Another study needed, which is right?

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