METHODS:The study analyzed 969 serum samples from 315 HC, 411 relapsing remitting MS (RR-MS), 128 secondary progressive MS (SP-MS), 33 primary progressive MS (PP-MS) and 82 patients with other neurological diseases for autoantibodies against two putative MS antigens CSF114(Glc) and KIR4.1a and KIR4.1b and against 24 key endogenous antigens linked to diseases such as vasculitis, systemic sclerosis, rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus, polymyositis, scleroderma, polymyositis, dermatomyositis, mixed connective tissue disease and primary biliary cirrhosis. Associations with disability and MRI measures of lesional injury and neurodegeneration were assessed.
RESULTS:The frequencies of anti-KIR4.1a and anti-KIR4.1b peptide IgG positivity were 9.8% and 11.4% in HC compared to 4.9% and 7.5% in RR-MS, 8.6% for both peptides in SP-MS and 6.1% for both peptides in PP-MS (p = 0.13 for KIR4.1a and p = 0.34 for KIR4.1b), respectively. Antibodies against CSF114(Glc), KIR4.1a and KIR4.1b peptides were not associated with MS compared to HC, or with MS disease progression. HLA DRB1*15:01 positivity and anti-Epstein Barr virus antibodies, which are MS risk factors, were not associated with these putative MS antibodies.
CONCLUSIONS:Antibody responses to KIR4.1a and KIR4.1b peptides are not increased in MS compared to HC nor associated with MS disease progression. The frequencies of the diverse autoreactive antibodies investigated are similar in MS and HC.
Not so long ago we had a study claiming that about 50% of MSers had an antibody against this potassium channel and that was a target for the cause of MS.
Potassium channel KIR4.1 as an immune target in multiple sclerosis.Srivastava R, Aslam M, Kalluri SR, Schirmer L, Buck D, Tackenberg B, Rothhammer V, Chan A, Gold R, Berthele A, Bennett JL, Korn T, Hemmer B. N Engl J Med. 2012;367(2):115-23.
Three years on and this has not been replicated by anyone, including this new study and where Kir4.1 reactive antibodies are no particularly common in MS.
Nerrant E, Salsac C, Charif M, Ayrignac X, Carra-Dalliere C, Castelnovo G, Goulabchand R, Tisseyre J, Raoul C, Eliaou JF, Labauge P, Vincent T.Lack of confirmation of anti-inward rectifying potassium channel 4.1 antibodies as reliable markers of multiple sclerosis. Mult Scler. 2014;20:1699-703.
Brickshawana A, Hinson SR, Romero MF, Lucchinetti CF, Guo Y, Buttmann M, McKeon A, Pittock SJ, Chang MH, Chen AP, Kryzer TJ, Fryer JP, Jenkins SM, Cabre P, Lennon VA.Investigation of the KIR4.1 potassium channel as a putative antigen in patients with multiple sclerosis: a comparative study. Lancet Neurol. 2014; 13: 795-806
This quite typical the claims of autoantigens or MS after a big fanfare it seems to turn to keich and so the search for the cause keeps on