NEUTRALIZING ANTIBODY RESPONSES IN THE MAJOR IMMUNOGLOBULIN CLASSES TO YELLOW FEVER 17D VACCINATION OF HUMANS

Abstract

Monath, T. P. C. (CDC, Atlanta, Ga. 30333). Neutralizing antibody responses in the major immunoglobulin classes to yellow fever 17O vaccination of humans. Amer J Epidem 93: 122–129, 1971.—The antibody response in individual immunoglobulin fractions was measured in human volunteers vaccinated with yellow fever (YF) 17D virus. Sera were fractionated by gel filtration; neutralizing antibodies were measured by a constant virus-serum dilution plaque reduction technique in BHK-21 cell cultures. Neutralizing antibodies in whole sera were present by the eighth day following vaccination. IgM antibodies were first detected on days 8 or 9, rose to high titers between days 14 and 17, and tended to decline-gradually thereafter. During the first 4–6 weeks following vaccination IgM antibody titers were 16- to 256-fold higher than IgG antibody; significant amounts of IgM antibody were present as long as 82 days following primary vaccination. IgG antibodies appeared later than IgM, between 10 and 17 days after vaccination, tended to-remain stable or to rise slightly thereafter, and did not surpass IgM titers. IgM antibody in significant amounts was present 18 months after last vaccination in an individual with multiple prior exposures to YF 17D virus. For both IgM and IgG antibodies, a high degree of specificity was demonstrated in neutralization test using various strains of YF virus and heterologous Group B arboviruses. The prolonged synthesis of IgM antibody suggested persistence of antigenk stimulation.