The Recognition of Water‐Soluble I Blood Group Substance¹

Abstract

Abstract. A powerful cold auto anti‐I has been found that is strongly inhibited by hydatid cyst fluid and inhibited to a varying extent by all of the 181 human saliva samples tested. The investigation showed that the inhibition effect was specific for I and that water soluble I blood group substance must be responsible. No correlation could be found between the concentration of I substance in the saliva and the presence of ABH, Lewis or Sda substances. The amount of salivary I substance secreted appears to be a constant feature of the individual. Infants at birth and i adults have high concentrations of I substance in their saliva and the amount of I substance present does not reflect the I status of the red cells.