The extent of inhibition correlates with number of epitopes recognized. All monoclonal antibodies used in this experiment recognize different epitopes on MV-H and neutralize MV. (A) Bone marrow cells from MV immune cotton rats were stimulated with MV in an ELISPOT system without antibody, with one monoclonal or a combination of 3 monoclonal antibodies (amount of antibody was constant at a neutralization titer of 0.5). The addition of a single antibody reduced the number of stimulated MV-specific B cells (*P < .05), whereas addition of a triple antibody combination reduced the number of stimulated MV-specific B cells to a higher degree (***P < .001). The difference between single antibody and triple antibody combination was statistically significant (P < .05). (B) To determine differences in the ability of antibody (combinations) to inhibit seroconversion after vaccination, cotton rats were inoculated with a low amount of MV-H–specific monoclonal antibodies individually or combinations of 3 MV-H–specific monoclonal antibodies (all at 1 mL of a neutralization titer of 100). Although injection of single antibody reduced the generation of neutralizing antibodies after immunization (**P < .01), injection of the triple antibody combination reduced it to a significantly higher degree (***P < .001). The difference between single antibody and triple antibody combination was statistically significant (P < .05).