CHANGES WITHIN T-CELL RECEPTOR V-BETA SUBSETS IN INFANTS FOLLOWING MEASLES VACCINATION

Measles produces immune suppression which contributes to an increased susceptibility to other infections. Recently, high titered measles vac cines have been linked to increased long-term mortality among some fem ale recipients. Because the mechanisms by which wild-type or attenuate d live-vaccine strains of measles virus alter subsequent immune respon ses are not fully understood, this prompted an examination of the chan ges within the peripheral blood T cell receptor V-beta repertoire foll owing measles immunization. Twenty-four 6- and 9-month-old infants wer e studied at 2 weeks and 3 months following immunization by semiquanti tative reverse transcription-polymerase chain reaction. There was a si gnificant increase in V(beta)2 expression (P < 0.05), and a decrease i n the V(beta)4 subset (P < 0.03) 2 weeks following vaccination with su bsequent return to baselines at 3 months in vaccine recipients who ser oconverted. These data suggest that measles virus may affect immune re sponses in part by altering the T cell receptor repertoire. (C) 1996 A cademic Press, Inc.