AN IN-VITRO MODEL TO STUDY THE EFFECT OF ANTIBODIES AND CELL-RECEPTORANALOGS ON MENINGOCOCCAL ADHERENCE TO HUMAN OROEPITHELIAL CELLS

We have investigated different experimental schedules to achieve adher ence of Neisseria meningitidis group B to cultured and buccal epitheli al cells (BEG) and the effect of antibodies and receptor analogues on bacterial adherence. No adherence of meningococcus was observed when H eLa, HEp-2 or KB cells were used, but high rates of adherence to BEC o ccurred. The effect of antibodies on bacterial adherence was studied i n assays carried out in the presence of saliva and serum collected fro m convalescing children with meningococcal meningitis and children vac cinated with VAMENGOC B-C. Both saliva and serum from the convalescent patients inhibited the adherence of meningococci, but saliva and seru m from vaccinated children did not, corroborating our previous data of a poor antibody response induced by this vaccine. Human colostrum did not affect meningococcal adherence despite the presence of antibodies to N. meningitidis detected by ELISA. Inhibition of adherence by sera from an immunized horse, rabbits and mice, as well as by cell recepto r analogues (outer-membrane complex and purified polysaccharide C), wa s observed. Our results show that up to now BEC continue to be the bes t cells to study meningococcal adherence and the effect of adherence i nhibitors.