Antibodies in human filariasis sera react with diethylcarbamazine.

We demonstrate by an ELISA the presence of antibodies in human filarial sera that react with diethylcarbamazine (DEC); they appear to be primarily filarial antibodies cross-reacting with DEC skeleton, since affinity-purified DEC antibodies strongly react with Wuchereria bancrofti microfilariae. These observations indicate a possible antigenic mimicry between the drug and some parasite component.