ELISA reactivity and tolerization to GCR in six representative seroconverted patients. Sera from individual patients were analyzed during their course of therapy by ELISA and RIP. The arrows indicate the time of seroconversion (RIP⁺) and the time of tolerization (RIP^-). A patient was considered seroconverted if a positive ELISA result was confirmed by RIP and tolerized if after seroconversion, both ELISA and RIP of subsequent sera samples were negative.