Multiple Sclerosis: Enzymatic Cross Site-Specific Recognition and Hydrolysis of H2A Histone by IgGs against H2A, H1, H2B, H3 Histones, Myelin Basic Protein, and DNA

Abstract

Histones have a paramount role in chromatin remodeling and gene transcription. Free histones are damage-associated molecules in the blood; administration of histones to animals drives systemic inflammatory and toxic effects. Myelin basic protein (MBP) is the most crucial component of the axon myelin-proteolipid sheath. Antibodies-abzymes with different enzymatic activities are very toxic and an essential feature of some autoimmune diseases. Electrophoretically homogeneous IgGs against H1, H2A, H2B, H3, H4, MBP, and DNA were derived from sera of multiple sclerosis (MS) patients by several affinity chromatographies. Using MALDI-TOFF mass spectrometry, it was shown that IgGs against H2A split H2A at 12 sites; the number of H2A hydrolysis sites by antibodies against other antigens is different: H1 (19), H2B (11), H3 (15), H4 (9), MBP (10), and DNA (23), and they only partly match. Thus, the complex formation polyreactivity and the enzymatic cross-activity of pernicious humans IgGs against five histones, MBP, and DNA have been shown for the first time. The data obtained indicate that the formation of such polyspecific-polyreactive abzymes, whose single active center can recognize and hydrolyze different substrates, can occur due to the formation of antibodies against hybrid antigenic determinants consisting of several histone protein sequences. IgGs with high affinity for DNA with DNase and protease activities may be antibodies against DNA-histone complex antigenic determinants, including protein and DNA sequences. Polyreactive IgGs-abzymes against MBP, five histones, and DNA with extended cytotoxicity can play a very negative role in the pathogenesis of multiple sclerosis and probably other different diseases.

Keywords: DNA; H1; H2A; H3; H4 histones; IgGs against H2B; catalytic abzymes; enzymatic cross recognition and hydrolysis; human blood sera antibodies-abzymes; hydrolysis of H2A histone; multiple sclerosis patients; myelin basic protein.

Figure 1

SDS-PAGE analysis hydrolysis of five histones (H1–H4) by IgGs-abzymes against these five histones (lane a-H) as well as MBP (lane a-M) (A) and human myelin basic protein by IgGs against five histones (lane a-H) and Abs-abzymes against MBP (lane a-M) (B). MBP and a mixture of five histones with and without IgGs (0.03 mg/mL) were incubated for 12 h. Lane C corresponds to the histones (A) and MBP (B) incubated without IgGs. Lane K—proteins with known molecular masses (A,B).

Figure 2

Analysis of the relative activity of IgGs against DNA, five different histones, and MBP in the hydrolysis of scDNA for 3 h. Designations of IgGs are shown in the Figure.

Figure 3

MALDI spectra show H2A histone (0.8 mg/mL) over time during hydrolysis (0–20 h) in the presence of IgGs (0.045 mg/mL) against H2A (A–E).

Figure 4

MALDI spectra corresponding to H2A histone (0.8 mg/mL) over time during hydrolysis in the presence of IgGs (0.04 mg/mL) against H1 (A,B) and H2B (C–F).

Figure 5

MALDI spectra demonstrating in time hydrolysis of H2A by IgGs (0.04 mg/mL) against H3 histone (A–D) and H4 histones (E).

Figure 6

Sites of H2A hydrolysis by IgGs against H2A (A), H1 (B), H2B (C), H3 (D), H4 (E), MBP (F), and DNA (G). Major sites of H2A splitting are marked by big stars (★), moderate ones by arrows (↓), and minor sites of the cleavages by small stars (*) (A–F).

Figure 7

MALDI spectra demonstrate in time hydrolysis of H2A by IgGs (0.04 mg/mL) against MBP (A) and DNA (B).