Prlnted In U.S.A. HUMAN PERIPHERAL BLOOD LYMPHOCYTES FROM RECENTLY VACCINATED REACTING NEUTRALIZING ANTIBODY ON IN VITRO STIMULATION WITH ONE TYPE OF POLIOVIRUS' INDIVIDUALS PRODUCE BOTH TYPE-SPECIFIC AND INTERTYPIC CROSS-

An in vitro system of poliovirus-specific antibody production by peripheral blood B cells on stimula-tion by the virus has been developed. Virus-neutral-izing antibodies in culture supernatant fluids, or virus-specific antibody-secreting cells (ASC) were detected by microneutralization assay and ELISA-SPOT test, respectively. After booster immunization with polio vaccine, anti-poliovirus-neutralizing ASC were present in circulation. This response was measurable between 5 and 12 days after booster vaccination, At between 12 and 90 days, another subset of B cells was found in peripheral blood that only produced poliovirus-specific neutralizing antibody after in vitro anti-genic stimulation. The in vitro virus-induced re