Sialic Acid Deficiency of Human Red Blood Cells Associated with Persistent Red Cell, Leucocyte, and Platelet Polyagglutinability

Summary. This study reports, for the first time, a persistent polyagglutinability involving all blood cells of a patient. The phenomenon is shown to be an immunological reaction due to an antibody present in sera of all normal adults, whereas the antigen, tentatively designated ‘T_cr’, is unique to the patient. It is shown that T_cr is related to T_n, an antigen previously described in association with red cell polyagglutinability. A partial deficiency of red cell sialic acid is also found to be associated with this abnormality. It is suggested that this sialic acid deficiency may be a manifestation of a primary underlying muco‐protein abnormality.