The erythrocyte and epithelial cell receptors for Haemophilus influenzae are expressed independently.

The Anton blood group antigen has been shown to be the erythrocyte receptor for Haemophilus influenzae. Cord erythrocytes, which lack the Anton antigen, were not agglutinated by H. influenzae (L. van Alphen, J. Poole, and M. Overbecke, FEMS Microbiol. Lett. 37:69-71, 1986). Twenty-eight erythrocyte suspensions from newborns less than 4 days old were also not agglutinated, but 23 of 56 erythrocyte suspensions from 4- to 50-day-old newborns and 23 of 35 erythrocyte suspensions from older infants were agglutinated. Positive hemagglutination correlated with the presence of the Anton antigen on the erythrocytes for 163 of 173 (P less than 0.0001). Adherence of H. influenzae to buccal epithelial cells obtained from six newborns within 3 days after birth was as strong as that found with adult epithelial cells, whereas the erythrocytes from five of six of these newborns were not agglutinated by the bacteria. Adherence of H. influenzae to epithelial cells of 15 donors was not inhibited by anti-Anton serum. Moreover, H. influenzae carrying fimbriae adhered to epithelial cells of an Anton-negative donor. From these results we conclude that the age at which the erythrocyte receptor for H. influenzae is expressed is the same as for the Anton antigen, but that the receptor on the epithelial cells is already expressed at birth and is not identical to the Anton antigen.