Cellbind

A micro column immunofixation system

The Cellbind Screen assay is a micro column test system in which sensitised red cells from a suspension are caught by a gel matrix containing anti-IgG, anti-IgM, and anti-C3d in an enhancing high-density medium.

The strongest advantages of Cellbind are the flexibility and the easy readable outcome.

  1. Flexibility: Cellbind Screen is intended for use in the detection or identification of red cell antibodies, as well as for blood grouping, crossmatching and the modified direct antiglobulin test (DAT, for the detection of in vivo coating of red blood cells with antibodies and complement components).
  2. Easy to read: In positive reactions, red blood cells will be caught in the top layer of the gel matrix. In negative reactions, only a discrete button of red cells at the bottom of of the micro column will be seen. Interpreting results, either manually or with a reader, is very easy and unambiguous.
  3. Easy for automation: Cellbind Screen is suitable for use in manual, as well as (semi-)automated systems. The test is based on the immunofixation of sensitised red blood cells in a micro column containing a gel matrix. The cell suspension is added to the incubation compartment of the micro column, together with the plasma, serum or blood grouping reagents to be tested.

Procedure

During the incubation phase antigen-positive red blood cells will bind the corresponding anti-red blood cell antibodies present in the plasma, serum or reagent. Next, the cards are subjected to three steps of centrifugation:

  • In the first phase optimally sensitised red blood cells are caught by ligands: anti-IgG, anti-IgM and anti-C3d in an enhancing High Density Medium. This results in a 3-dimensional network of red blood cells, attached to each other by these ligands.
  • In the second phase this network is compressed into aggregates during landing on the surface of the gel.
  • In the third phase non-sensitised red blood cells will move towards the bottom of the micro column.