The gel test: a new way to detect red cell antigen‐antibody reactions

Abstract

A new process for the detection of red cell (RBC) antigen antibody reactions is described. It is applicable to most of the tests performed in blood group serology. The procedures are standardized and easy, and they provide clear and stable reactions that improve the interpretation of results. The process uses special microtubes filled with a mixture of gel, buffer, and reagent. Depending on the test to be carried out, the test uses a neutral gel containing no reagents (reagents are added to top of gel) or a specific gel containing reagents (e.g., antiglobulin serum or anti-A, -B, -D, etc.). A suspension of RBCs (for typing or the direct antiglobulin test) or a mixture of RBCs and serum (for reverse ABO typing or antibody characterization) is centrifuged through the gel under precise conditions. In negative reactions, the RBCs pass through the gel and pellet in the bottom of the tube, whereas, in positive reactions, they are trapped in the gel and the reaction may be read for hours afterwards. The test is easy to perform, sensitive, and reproducible. The antiglobulin tests can be performed without washing of the RBCs. There should be a reduction of risk from biohazardous materials.

Comparative Study of Blood Cross Matching Using Conventional Tube and Gel Method

“…The technology was developed by Lapierre et al [4]. The basic principle of the gel test is that instead of a test tube, the serum and cell reaction takes place in a microtube.…”

“…Lapierre [1,2] introduced gel tests using principle of controlled centrifugation of red cells through sephadex gel contained within a microtube. The gel technique is useful for ABO and Rh typing, cross matching Direct and Indirect Antiglobulin Tests (DAT and IAT) and identification of alloantibodies [3][4][5][6].…”

Canine idiopathic immune-mediated haemolytic anaemia: a review with recommendations for future research

“…The direct Coombs' test is still the main method used to demonstrate anti-erythrocyte antibodies, alternative methods, however, include flow cytometry (Morley et al 2008), enzyme-linked immunosorbent assay (Jones et al 1987), and a gel test (Lapierre et al 1990), although these tests are not routinely available in veterinary practice. The diagnostic performance of the direct Coombs' test depends on many factors, such as use of polyspecific instead of monospecific Coombs reagents, a one-dilution only tube test instead of multititre plates, and incubation at 37 C only versus additional incubation at 4 C (Wardrop 2005).…”

Prolonged red cell aplasia after major ABO-incompatible allogeneic hematopoietic stem cell transplantation: removal of persisting isohemagglutinins with Ig-Therasorb® immunoadsorption

“…6 Blood group, Rhesus typing and hemagglutinin titers Rhesus typing and identification of complete and incomplete anti-RBC alloantibodies and direct antiglobulin testing were performed by standard methods. 14,15 Commercial reagents (DiaMed-ID system, Cressiesur-Morat, Switzerland) were used according to the manufacturer's instructions. Titers of anti-A and anti-B hemagglutinins in case of blood group incompatibilty were determined before the start of the conditioning regimen, then weekly until discharge, and thereafter biweekly until stable RBC engraftment had occurred.…”

“…14 To document any treatment benefit of immunoadsorption, a relative hemagglutinin score was evaluated by using the DiaMed-ID microtyping system (results are given as strength of agglutination, rated 0-4). 15 All patients had peripheral blood and reticulocyte counts performed on a daily basis starting 7 days before HSCT until hematopoietic engraftment. Absolute neutrophil counts (ANCs) were calculated from leukocyte and differential counts.…”