Predicting autoimmunity after alemtuzumab treatment of multiple sclerosis.

Journal of Neurology, Neurosurgery, and Psychiatry

PubMedID: 24368840

Azzopardi L, Thompson SA, Harding KE, Cossburn M, Robertson N, Compston A, Coles AJ, Jones JL. Predicting autoimmunity after alemtuzumab treatment of multiple sclerosis. J Neurol Neurosurg Psychiatr. 2014;85(7):795-8.
OBJECTIVE
We have previously shown that autoimmunity following alemtuzumab treatment of multiple sclerosis can be predicted by high baseline serum interleukin IL-21 (IL-21), as measured using a now 'redundant' enzyme linked immunosorbent assay (ELISA). Here we ask whether currently available ELISAs have similar prognostic value.

DESIGN
Serum IL-21 from 141 individuals with relapsing remitting multiple sclerosis was measured using the now 'redundant' IL-21 ELISA and five further currently available kits. All patients had been treated with alemtuzumab; 61/141 had developed secondary autoimmunity.

RESULTS
The 'redundant kit', and one current kit, confirmed higher baseline serum IL-21 in patients with autoimmunity (542 pg/mL vs. 222 pg/mL and 53.1 pg/mL vs. 9.3 pg/mL respectively) and showed positive correlation. However, only the 'redundant' kit had predictive utility.

CONCLUSIONS
Currently available IL-21 ELISA kits should not be used to counsel individuals with multiple sclerosis considering treatment with alemtuzumab.