Low-ionic strength solutions (LISS) increase the interaction of antigen and antibody in immuno hematologic reactions.

The solutions reduced of ionic strength are used to accelerate the interaction of antigen and antibody. That solution of saline containing less Na and Cl ions than normal isotonic salt solutions interfere less in the reaction between an antigen and antibody of complementary electrostatic charge. These solutions are known in immunohematology as Low Ionic Strength Saline (LISS). LISS solution is used for preparing 5% red cell suspensions for blood grouping as well as 0.8% red cell suspensions for cross matching, antibody screening, direct anti-human globulin test.