Abstract
Molecular mimicry in the broad sense is structural, functional or immunologic similarity between unrelated macromolecules (Oldstone, 1998). In biomedical studies this phenomenon is discussed as the most proven mechanism of triggering/prevention of autoimmune diseases (Kivity et al., 2009). In this paper, we isolate and structurally identify the yeast biopolymers (BPs) that selectively bind human autoantibodies to thyroid peroxidase (TPO) and thyroglobulin (Tg) (anti-TPO and anti-Tg, respectively), e.g . immunologically mimic thyroid antigens. The BPs, viz. , BP anti-TPO and BP anti-Tg , were isolated from the soluble fraction of S. cerevisiae BIM Y-195 by affinity chromatography with anti-TPO or anti-Tg, respectively. Both affinity eluates, AE anti-TPO and AE anti-Tg , showed functional activity characteristic of BP anti-TPO and BP anti-Tg , viz , ability ( i) to distinquish anti-TPO (anti-Tg) from other IgG and ( ii ) to compete with TPO (Tg) for binding of anti-TPO (anti-Tg) in ELISA tests. The semi-preparative size exclusion chromatography of AE anti-TPO and AE anti-Tg with detection by refractometer gave a 5000-7000 Da fractions containing pure BP anti-TPO and BP anti-Tg , respectively, according to ELISA data. Analysis by two-dimensional NMR spectroscopy including 1 H, 1 H COSY and 1 H, 13 C HSQC experiments indicated that both substances are linear α-1, 6-glucans.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call