Etude rhéologique de la dissociation d'agglutinats immunologiques d'hématies A

Immunologic agglutination is the common consequence of the in vitro Antigen-Antibody reaction. Antibodies fixed to antigenic sites on the red cell membranes act as a molecular bridge adhering adjacent cells to form erythrocyte agglutinates. A little amount of energy is dissipated during this reaction. Agglutinates can be dissociated by providing enough energy which may be supplied by shear stress in a viscometer. In this paper a new technique is proposed to determine dissociation parameters of erythrocyte immunologic agglutinates using a laser backscattering method. Backscattered light intensity increases as the agglutinate dissociation is carried out by applying a controlled shear stress in a transparent Couette viscometer. Obtained curves of dissociation can be fitted by an exponential function. A numerical integration of the dissociation curves leads to the obtention of a parameter associated to the energy spent in the dissociation process. A satisfactory differentiation of erythrocyte subgroupes A1, A2, AB, AxB and Am has been carried out with this technique.