Reader response: Hashimoto encephalopathy in the 21st century
MakotoYoneda, Dean and Professor, Faculty of Nursing and Social Welfare Sciences, Fukui Prefectural University (Fukui, Japan)
AkikoMatsunaga, Staff, Faculty of Nursing and Social Welfare Sciences, Fukui Prefectural University (Fukui, Japan)
MasamichiIkawa, Senior Assistant Professor, Department of Advanced Medicine for Community Healthcare, Faculty of Medical Sciences, University of Fukui (Fukui, Japan)
Submitted September 10, 2020
Mattozzi et al.1 reported that the antibodies against ΝΗ2-terminal of α-enolase (NAE) were detected only in 1 of 24 (4%) suspected Hashimoto encephalopathy (HE) cases. Through a proteomic analysis, we previously discovered anti-NAE antibodies as a diagnostic marker of HE.2,3 Anti-NAE antibodies were identified in 19 of 78 (24%) sera of suspected HE patients with limbic encephalitis in our recent study.4
For the detection of anti-NAE antibodies, Mattozzi et al. used a lysate of HEK293 cells transfected with the plasmid containing NAE (NAE plasmid, the same domain referred in our paper2), while we have used recombinant NAE protein that was purified using a His column from lysates of NAE plasmid transfected cells in our studies.2–4 We tested the immunoreactivity of our serum samples using both methods—i.e., lysate (Mattozzi et al.) and purified recombinant protein (our laboratory) from NAE plasmid transfected HEK293. The sera of patients with HE demonstrated remarkably high quality of immunoreactivity to the purified recombinant NAE than to the transfected HEK293 lysate (Figure & Table available online).
Therefore, we assumed that Mattozzi et al. underestimated the diagnostic values of anti-NAE antibodies in HE. We recommend the use of purified NAE protein for the detection of anti-NAE antibodies.
Disclosure
The authors report no relevant disclosures. Contact journal@neurology.org for full disclosures.
References
Mattozzi S, Sabater L, Escudero D, et al. Hashimoto encephalopathy in the 21st century. Neurology 2020;94:e217–e224.
Fujii A, Yoneda M, Ito T, et al. Autoantibodies against the amino terminal of alpha-enolase are a useful diagnostic marker of Hashimoto's encephalopathy. J Neuroimmunol 2005;162:130–136.
Yoneda M, Fujii A, Ito A, Yokoyama H, Nakagawa H, Kuriyama M. High prevalence of serum autoantibodies against the amino terminal of alpha-enolase in Hashimoto's encephalopathy. J Neuroimmunol 2007;185:195–200.
Kishitani T, Matsunaga A, Ikawa M, et al. Limbic encephalitis associated with anti-NH2-terminal of α-enolase antibodies: A clinical subtype of Hashimoto encephalopathy. Medicine (Baltimore) 2017;96:e6181.
Mattozzi et al.1 reported that the antibodies against ΝΗ2-terminal of α-enolase (NAE) were detected only in 1 of 24 (4%) suspected Hashimoto encephalopathy (HE) cases. Through a proteomic analysis, we previously discovered anti-NAE antibodies as a diagnostic marker of HE.2,3 Anti-NAE antibodies were identified in 19 of 78 (24%) sera of suspected HE patients with limbic encephalitis in our recent study.4
For the detection of anti-NAE antibodies, Mattozzi et al. used a lysate of HEK293 cells transfected with the plasmid containing NAE (NAE plasmid, the same domain referred in our paper2), while we have used recombinant NAE protein that was purified using a His column from lysates of NAE plasmid transfected cells in our studies.2–4 We tested the immunoreactivity of our serum samples using both methods—i.e., lysate (Mattozzi et al.) and purified recombinant protein (our laboratory) from NAE plasmid transfected HEK293. The sera of patients with HE demonstrated remarkably high quality of immunoreactivity to the purified recombinant NAE than to the transfected HEK293 lysate (Figure & Table available online).
Therefore, we assumed that Mattozzi et al. underestimated the diagnostic values of anti-NAE antibodies in HE. We recommend the use of purified NAE protein for the detection of anti-NAE antibodies.
Disclosure
The authors report no relevant disclosures. Contact journal@neurology.org for full disclosures.
References