Latex. With the help of activated polymer it is possible to modify by a carbohydrate any aminated surface (Figure 1). The synthesis is performed as follows: the aminated matrix is treated with the polymer followed by the aminoalkyl glycoside, afterwards the excess of active groups is transformed into amides by the action of ethanolamine. The conditions of the attachment are similar to those in case of soluble probe synthesis.

Figure 1. Determination of titre of antibodies to blood group specific antigen A with the help of latex-agglutination on 96-well round bottom plates. (a) Atri-PAA (designated as capital letters ) is coated onto plastic; (b) anti-A antibodies are bound to the modified surface (left); (c) after washing the latex bearing immobilized antigen A is added; the latex specifically bound with antibodies covers uniformly the well surface (left), unbound latex is 'trickled' down to the well bottom; (d) the visible result reflects negative and positive results of the reaction respectively. - Atri-PAA, - antibodies; - modified latex particles.

Latex particles permit the visual monitoring of probes. The latex-label (usually brightly coloured) permitted the non-instrumental semiquantitative evaluation of antibody levels (Figure 1). For example, the determination of IgM and IgG antibody against blood group A and B antigens. A second example is the latex-diagnosticum for detecting anti-3,6-dimethylglucose IgM in sera of leprosy patients.
An alternative approach to the design of glycobeads and glycosurfaces is the modification of the material with avidin or streptavidin (or the use of commercially-available materials), followed by the attachment of Sug-PAA-biot, as described with magnetic beads.

Figure 2.

Magnetic beads coated with neoglycoconjugate were assessed for their ability to selectively isolate human cells with known anti-carbohydrate reactivity. Four lung cancer cell lines, NCI-H146, NCI-N417D, SKMES-I, EKVX; two acute lymphoblastic leukemia lines, MOLT-4 and CCRF-CEM; and the anti- Le^c hybridoma, LU-BGRU- G7, were tested. Sug-PAA bound uniformly to streptavidin coated magnetic beads as demonstrated by FITC labeled lectin. The anti- Le^c hybridoma cell line, LU BCRU-G7, demonstrated binding only to Le^c coated magnetic beads. Subsequent incubation in the presence of Le^c resulted in the release of the beads from the cell surface. Although there was some heterogeneity within the individual lung and leukemic cell lines, positive cells showed strong rosette formation with the coated beads. The A_di disaccharide coated beads showed binding in all four lung cancer cell lines, with the Le^c and the H (type1)-bead conjugates only reactive in the N417 and H146 SCLC lines. The range of L-selectin ligand-coated beads were all successful in binding to the acute lymphoblastic leukemia cell lines MOLT4 and CCRF-CEM. This approach provides a versatile model for the study of cell-surface carbohydrate interactions that should find application in many areas of cell biology.

Fluorescent particles (commercial material coated with streptavidin) after instant "glycosylation" with SiaLe^a-PAA-biot specifically bind activated (E-selectin expressing) HUVECs, see fluorescent microscopy data, Figure 3.

Figure 3. Stimulated HUVECs + SiaLea-PAA-flu BEADS	Unstimulated HUVECs

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