An analytical study of the functions of two phase media of liquid and gel with the microcolumn gel Coombs'test / 中国免疫学杂志

ABSTRACT

Objective:To analyse the functions of two phase media of Liquid and Gel with the Microcolumn Gel Coombs'Test and study the reasons for obviating the need of washing RBC in the Gel Coombs'T.Methods:Add tryplan blue solution into the wider upper portion of the microcolumn gel tube,observe the time of the tryplan blue solution diffusion into the Gel medium at the narrow bottom portion of the tube.Add tryplan blue solution into the liquid reactant in test tube,observe the time of the tryplan blue solution diffusion into the liquid medium.Results:In the Microcolumn of Gel Coombs'Test there is no visual mixing of the two phases for 6 h at lest which is much longer than the incubation time needed for antibody-antigen reaction in routine red cell serology.It takes more than 30 h for the 2 phases to mix.In the test tube of Coombs'Test the tryplan blue solution diffusion into the liquid reactant of serum,red cells and anti-globin reagents and turned to blue colour immediatedly.Conclusion:Two reasons for non-requirement of washing in Gel-Coombs'T have been found.Firstly,there are two phases of reactants in the tubes of cards,the AHG is present in the gel at the narrow bottom portion of the tube,and the RBC,the serum to be detected in the wider upper portion of the tube.Secondly,the gel serves as not only a medium for separating agglutinated RBC from the dispersed RBC,but as a medium for boosting the reactions of AHG with IgG sensitized RBCs.The crux of the two reasons is of the two phases of reactants.