New technologies in immunohaematology.

Since the discovery of the ABO system, numerous important innovations have contributed to a continuous, rapid evolution in the diagnostic methods for in vitro measurements of the antigen-antibody reaction, allowing a significant improvement in the compatibility between blood from donors and the recipients. Apart from the introduction of ABO typing, these methods include the determination of Rh type and phenotype, the direct and indirect antiglobulin tests, cross-matching and consequent identification of antigens and antibodies of clinical relevance, the use of low ionic strength additives and enzyme treatments, the development of monoclonal reagents and solid-phase and microcolumn platforms for performing the pre-transfusion tests. Since transfusion safety depends on a series of strictly inter-related processes1, among which pre-transfusion tests have a predominant role, in recent years some of the new technologies that integrate the classical techniques in immunohaematology have become valid instruments for improving the safety of transfusions. The aim of this review is to illustrate the principles and practical applications of these emerging techniques used in our laboratory to identify antigens and antibodies, in cases of red cell or platelet immunisation.