Monocyte NOTCH2 expression predicts IFN-β immunogenicity in multiple sclerosis patients

Abstract

Multiple sclerosis (MS) is an autoimmune disease characterized by CNS inflammation leading to demyelination and axonal damage. IFN-β is an established treatment for MS; however, up to 30% of IFN-β-treated MS patients develop neutralizing antidrug antibodies (nADA), leading to reduced drug bioactivity and efficacy. Mechanisms driving antidrug immunogenicity remain uncertain, and reliable biomarkers to predict immunogenicity development are lacking. Using high-throughput flow cytometry, NOTCH2 expression on CD14+ monocytes and increased frequency of proinflammatory monocyte subsets were identified as baseline predictors of nADA development in MS patients treated with IFN-β. The association of this monocyte profile with nADA development was validated in 2 independent cross-sectional MS patient cohorts and a prospective cohort followed before and after IFN-β administration. Reduced monocyte NOTCH2 expression in nADA+ MS patients was associated with NOTCH2 activation measured by increased expression of Notch-responsive genes, polarization of monocytes toward a nonclassical phenotype, and increased proinflammatory IL-6 production. NOTCH2 activation was T cell dependent and was only triggered in the presence of serum from nADA+ patients. Thus, nADA development was driven by a proinflammatory environment that triggered activation of the NOTCH2 signaling pathway prior to first IFN-β administration.

Expansion of Neutrophils and Classical and Nonclassical Monocytes as a Hallmark in Relapsing-Remitting Multiple Sclerosis

“…The latest revision of McDonald criteria stress the necessity of early diagnosis, classification, and therapy of new MS cases, hence justifying the search for novel disease markers (5,6,45,46). Apart from MRI-based and epidemiological disease hallmarks, attempts are made to link immune activation markers in blood and CSF with particular disease forms (21-23, 27, 47, 48), relapse or disability progression (20,21), and therapy response (2,23,25,28). Here, we demonstrate the usefulness of a simple flow cytometry-based quantification of circulating granulocytes, CD15 + neutrophils, and monocyte subsets in prediction of RRMSi.…”

“…In MS individuals, skewing of the typical pattern of monocyte sub-population distribution within pan-monocytes toward intermediate and nonclassical monocytes was described (24)(25)(26)(27)(28). To recapitulate these results, we first assessed the levels of monocyte subsets within the HLA-DR + pan-monocyte population in healthy individuals and MS patients stratified by disease course type and disease activity (Figure 1).…”

“…Owing to their functional relevance, immunophenotyping and quantification of circulating T and B cells as well as of monocytes and granulocytes are regarded as a promising approach in search for potential MS biomarkers (2,19,20). In particular, alterations of the monocyte-to-lymphocyte and neutrophil-to-lymphocyte ratio (21), expansion of suppressive and inflammatory neutrophils (18,22), and changes in relative distribution of monocyte subtypes (23)(24)(25)(26)(27)(28) were observed in MS patients and linked to disease activity, degree of disability (EDSS), and administration of DMT.…”

“…According to expression of specific surface molecules, cytokine secretion, and phagocytic activity, human monocytes can be classified into the major population of classical monocytes (CD14 ++ CD16 − ) and minor subpopulations of intermediate (CD14 ++ CD16 + ) and nonclassical monocytes (CD14 + CD16 + ) (29)(30)(31). Alterations of intermediate or nonclassical monocyte levels within the pan-monocyte population are associated with a plethora of inflammatory diseases (30,32,33), including MS (24)(25)(26)(27)(28). In MS, however, these reports provide partially conflicting data and often investigate only one type of MS disease course or do not differentiate between disease course types.…”

Using Serum Metabolomics to Predict Development of Anti-drug Antibodies in Multiple Sclerosis Patients Treated With IFNβ

“…However, our understanding of the biological parameters that contribute to an individual's risk of ADA development remains limited. To date, a small number of genetic and immunological parameters have been associated with ADA risk, including human leukocyte antigen (HLA) class II alleles (16), HLA and non-HLA associated single nucleotide polymorphisms (17), and NOTCH2 expression on monocytes (18). Thus, there remains an unmet demand for a predictive biomarker of immunogenicity against IFNβ, and a better understanding of the mechanisms underpinning ADA development is required.…”