Combinatorial antibody library from multiple sclerosis patients reveals antibodies that cross‐react with myelin basic protein and EBV antigen

Abstract

Multiple sclerosis (MS) is a widespread neurodegenerative autoimmune disease with unknown etiology. It is increasingly evident that, together with pathogenic T cells, autoreactive B cells are among the major players in MS development. The analysis of myelin neuroantigen-specific antibody repertoires and their possible cross-reactivity against environmental antigens, including viral proteins, could shed light on the mechanism of MS induction and progression. A phage display library of single-chain variable fragments (scFvs) was constructed from blood lymphocytes of patients with MS as a potential source of representative MS autoantibodies. Structural alignment of 13 clones selected toward myelin basic protein (MBP), one of the major myelin antigens, showed high homology within variable regions with cerebrospinal fluid MS-associated antibodies as well as with antibodies toward Epstein-Barr latent membrane protein 1 (LMP1). Three scFv clones showed pronounced specificity to MBP fragments 65-92 and 130-156, similar to the serum MS antibodies. One of these clones, designated E2, in both scFv and full-size human antibody constructs, was shown to react with both MBP and LMP1 proteins in vitro, suggesting natural cross-reactivity. Thus, antibodies induced against LMP1 during Epstein-Barr virus infection might act as inflammatory trigger by reacting with MBP, suggesting molecular mimicry in the mechanism of MS pathogenesis.

Mechanisms of autoimmunity in the central nervous system: Disturbance of natural autoimmunity, infectious agents, cell contribution and antibody signatures

“…Structural alignment showed high homology within variable regions with CSF-MS-associated antibodies, as well as with antibodies reactive to the EBV latent membrane protein 1 (LMP1). 85 One of these clones, designated as E2, was shown to react with both MBP and LMP1 proteins in vitro, suggesting natural cross-reactivity. Based on such findings, antibodies induced against LMP1 during EBV infection could act as inflammatory templates by cross-reactivity against MBP.…”

“…Based on such findings, antibodies induced against LMP1 during EBV infection could act as inflammatory templates by cross-reactivity against MBP. 85 Environmental risk factors and vitamin D deficiency have also been implicated in the onset of CNS autoimmunity (MS). 86,87 However, in other autoimmune conditions affecting the CNS, such environmental factors are unknown (Table 1).…”

Multiple Sclerosis and Treatment: Drug Management and Nutrition with Exercise

“…The long latitude, as we move away from the equator, is associated with an increased incidence of MS, an association that has declined over the past decades. Latitude is associated with a variety of environmental factors, most notably, the exposure to solar radiation [2,[5][6].…”

“…At older ages the frequency decreases, and rarely occurs in individuals over 50 years of age when the frequency is equalized between the two sexes. In Europe, the prevalence rate of the disease is estimated at 83:100,000 and the mean annual incidence [2,[5][6]. MS is characterized by inflammatory lesions in the CNS.…”

Heterogeneous catalysis on the phage surface: Display of active human enteropeptidase

“…The DNA fragment encoding L-HEP/C122S was amplified by PCR using specific forward (5 0 -TATTCGTCTCTCATGGCCATTGTTGGTGG CTCTAACGCC-3 0 ) and reverse (5 0 -TATTAAGTCGACGCATGCAGAAAG CTCTGGATCCATT-3 0 ) primers carrying the respective BsmBI and SalI restriction sites (underlined). The amplified gene fragment was cleaved by these endonucleases and cloned into a modified phagemid vector pHEN2m [32] at NcoI and XhoI sites upstream of the sequence encoding phage g3p and downstream of a signal peptideencoding sequence. A GS linker (SS(G 4 S) 2 GGS) followed by 6 Â His and c-myc tag sequences was appended to the C-terminus of L-HEP.…”