DEVELOPMENTAL AND ENVIRONMENTAL-FACTORS THAT ENHANCE BINDING OF BORDETELLA-PERTUSSIS TO HUMAN EPITHELIAL-CELLS IN RELATION TO SUDDEN-INFANT-DEATH-SYNDROME (SIDS)

Asymptomatic infection due to Bordetella pertussis has been suggested to be one cause of sudden infant death syndrome (SIDS), We examined de velopmental and environmental factors previously found to affect bindi ng of another toxigenic species, Staphylococcus aureus, to human epith elial cells: expression of the Lewis(a) antigen; infection with respir atory syncytial virus (RSV); exposure to cigarette smoke; and the inhi bitory effect of breast milk on bacterial binding. Binding of two stra ins of B. pertussis (8002 and 250825) to buccal epithelial cells was s ignificantly reduced by treating the cells with monoclonal antibodies to Lewis(a) (P < 0.05) and Lewis(x) (P < 0.01) antigens. Both strains bound in significantly greater numbers to cells from smokers compared with cells from non-smokers (P < 0.05), HEp-2 cells infected with RSV subtypes A or B had higher binding indices for both 8002 (P < 0.001) a nd 250825 (P < 0.01). On RSV-infected cells, there was significantly e nhanced binding of monoclonal antibodies to Lewis(x) (P < 0.05), CD14 (P < 0.001) and CD18 (P < 0.01); and pre-treatment of cells with anti- CD14 or CD18 also significantly reduced binding of both strains of B. pertussis. Pre-treatment of the bacteria with human milk significantly reduced their binding to epithelial cells. The results are discussed in relation to our three-year survey of bacterial carriage among 253 h ealthy infants, their mothers and local SIDS cases between 1993-1995 a nd in relation to the change to an earlier immunisation schedule for i nfants and the recent decline in SIDS in Britain.