A repertoire of anti-mannan Candida albicans antibodies in the blood sera of healthy donors

ASCA-related antibodies in the blood sera of healthy donors and patients with colorectal cancer: characterization with oligosaccharides related to Saccharomyces cerevisiae mannan

“…Obtained biotinylated oligosaccharides were immobilized on avidin-coated plates and used for sera screening. It appeared that biotinylated α-linked mannosides 1, 2, 4, and 5 did not show any significant signals for healthy donor sera (Figure 3) or for patients with colorectal cancer (Solovev et al, 2023). We hypothesized that loading of oligosaccharide ligands onto microtiter well surfaces with higher density may improve the sensitivity of ELISA and permit better detection of low-affinity antibodies.…”

“… Screening results of IgG antibodies to oligosaccharides 1–5 in the blood sera of healthy donors using biotinylated conjugates of oligosaccharides 1–5 ( Solovev et al, 2023 ). …”

“…Moreover, low-affinity IgM antibodies with 10 binding centers are more easily detectable than IgG antibodies with two binding centers. Nevertheless, carbohydrate displays with low ligand density are more suitable for fine differentiation of antigenic properties of different ligands ( Solovev et al, 2023 ).…”

“…This was demonstrated by several examples. Particularly, our previous works showed that βoligomannoside fragments of Candida albicans mannan (Figure 1A) generated a higher antibody response than antigenic factors with solely α-linked chains (Solovev et al, 2023). The specificity of the monoclonal antibody EBCA-1 used in sandwich immune assay to detect Candida mannan was recently reinvestigated, and it was shown that EBCA-1 recognizes the trisaccharide β-Man-(1→2)-α-Man-(1→2)-α-Man and not homo-α-(1→2)-linked pentamannoside, as reported previously (Jacquinot et al, 1998;Krylov et al, 2021).…”

“…Fungal cell-wall polysaccharides are dominant surface antigens stimulating immune reactions in humans ( Erwig and Gow, 2016 ). The heterogeneity and high variability of substructures in polysaccharides lead to a multiplicity of so-called “antigenic factors” ( Suzuki, 1997 ) and the generation of a repertoire of antibodies with varying specificity ( Solovev et al, 2023 ). Moreover, the ability of different carbohydrate structures to elicit an antibody response varies depending on their structure.…”