Expression of interleukin-2 receptor alpha and CD45RO antigen on T lymphocytes cultured with rubella virus antigen, compared with humoral immunity inrubella vaccinees

We studied the expression of interleukin-2 receptor alpha (CD25)(+)CD45RO()CD4(+) T lymphocytes (T-cell activation) in response to the rubella virus (RV) antigen (Matsuura strain, Biken, Osaka, Japan) using three-color-stain ing Bow cytometry. The subjects were 48 healthy children (3-14 years old, 3 1 boys and 17 girls), who had received either monovalent vaccine (n = 5; me an age, 13.2 years) or measles-mumps-rubella (MMR) vaccine (n = 21; mean ag e, 10.5 years), had been naturally infected (n = 5; mean age, 11.4 years), or had been neither vaccinated nor naturally infected (n = 17; mean age, 10 .0 years) and 62 healthy adolescents and adults (15-37 years old; 19 males and 43 females), who had received monovalent vaccine (n = 26, mean age, 27. 4 years), had been naturally infected (n = 8; mean age, 24.0 years), or had been neither vaccinated nor naturally infected (n = 8, mean age, 16.5 year s). Ninety-four of 110 subjects had HI titers greater than or equal to 1.16 . T-cell activation in these subjects was significantly higher than that in 6 seronegative (HI titers < 1:8) subjects (p < 0.05). T-cell activation di d not differ significantly with the history of exposure to RV. HI antibody liters greater than or equal to 1:16 and T-cell activation persisted in vac cinated subjects for greater than or equal to 20 years and was similar to t hose in naturally infected subjects. Our results suggest that cell-mediated immunity and humoral immunity persist for at least 20 years after vaccinat ion. (C) 1999 Elsevier Science Ltd. All rights reserved.